Commit message: bpf: Dont allow vmlinux BTF to be used in map_create and prog_load.

The syzbot got FD of vmlinux BTF and passed it into map_create which caused
crash in btf_type_id_size() when it tried to access resolved_ids. The vmlinux
BTF doesn't have 'resolved_ids' and 'resolved_sizes' initialized to save
memory. To avoid such issues disallow using vmlinux BTF in prog_load and
map_create commands.

Fixes: 5329722057d4 ("bpf: Assign ID to vmlinux BTF and return extra info for BTF in GET_OBJ_INFO")
Reported-by: syzbot+8bab8ed346746e7540e8@syzkaller.appspotmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/bpf/20210307225248.79031-1-alexei.starovoitov@gmail.com
CVE: CVE-2021-29648
CWE: CWE-307
Vulnerability description: An issue was discovered in the Linux kernel before 5.11.11. The BPF subsystem does not properly consider that resolved_ids and resolved_sizes are intentionally uninitialized in the vmlinux BPF Type Format (BTF), which can cause a system crash upon an unexpected access attempt (in map_create in kernel/bpf/syscall.c or check_btf_info in kernel/bpf/verifier.c), aka CID-350a5c4dd245.

Project: linux
File: syscall.c

void bpf_map_put(struct bpf_map *map)
{
	__bpf_map_put(map, true);
}

Project: linux
File: syscall.c

static unsigned long bpf_map_memory_footprint(const struct bpf_map *map)
{
	unsigned long size;

	size = round_up(map->key_size + bpf_map_value_size(map), 8);

	return round_up(map->max_entries * size, PAGE_SIZE);
}

Project: linux
File: syscall.c

static int tracing_bpf_link_attach(const union bpf_attr *attr, struct bpf_prog *prog)
{
	if (attr->link_create.attach_type != prog->expected_attach_type)
		return -EINVAL;

	if (prog->expected_attach_type == BPF_TRACE_ITER)
		return bpf_iter_link_attach(attr, prog);
	else if (prog->type == BPF_PROG_TYPE_EXT)
		return bpf_tracing_prog_attach(prog,
					       attr->link_create.target_fd,
					       attr->link_create.target_btf_id);
	return -EINVAL;
}

Project: linux
File: syscall.c

static int bpf_task_fd_query_copy(const union bpf_attr *attr,
				    union bpf_attr __user *uattr,
				    u32 prog_id, u32 fd_type,
				    const char *buf, u64 probe_offset,
				    u64 probe_addr)
{
	char __user *ubuf = u64_to_user_ptr(attr->task_fd_query.buf);
	u32 len = buf ? strlen(buf) : 0, input_len;
	int err = 0;

	if (put_user(len, &uattr->task_fd_query.buf_len))
		return -EFAULT;
	input_len = attr->task_fd_query.buf_len;
	if (input_len && ubuf) {
		if (!len) {
			/* nothing to copy, just make ubuf NULL terminated */
			char zero = '\0';

			if (put_user(zero, ubuf))
				return -EFAULT;
		} else if (input_len >= len + 1) {
			/* ubuf can hold the string with NULL terminator */
			if (copy_to_user(ubuf, buf, len + 1))
				return -EFAULT;
		} else {
			/* ubuf cannot hold the string with NULL terminator,
			 * do a partial copy with NULL terminator.
			 */
			char zero = '\0';

			err = -ENOSPC;
			if (copy_to_user(ubuf, buf, input_len - 1))
				return -EFAULT;
			if (put_user(zero, ubuf + input_len - 1))
				return -EFAULT;
		}
	}

	if (put_user(prog_id, &uattr->task_fd_query.prog_id) ||
	    put_user(fd_type, &uattr->task_fd_query.fd_type) ||
	    put_user(probe_offset, &uattr->task_fd_query.probe_offset) ||
	    put_user(probe_addr, &uattr->task_fd_query.probe_addr))
		return -EFAULT;

	return err;
}

Project: linux
File: verifier.c

static int visit_insn(int t, int insn_cnt, struct bpf_verifier_env *env)
{
	struct bpf_insn *insns = env->prog->insnsi;
	int ret;

	/* All non-branch instructions have a single fall-through edge. */
	if (BPF_CLASS(insns[t].code) != BPF_JMP &&
	    BPF_CLASS(insns[t].code) != BPF_JMP32)
		return push_insn(t, t + 1, FALLTHROUGH, env, false);

	switch (BPF_OP(insns[t].code)) {
	case BPF_EXIT:
		return DONE_EXPLORING;

	case BPF_CALL:
		ret = push_insn(t, t + 1, FALLTHROUGH, env, false);
		if (ret)
			return ret;

		if (t + 1 < insn_cnt)
			init_explored_state(env, t + 1);
		if (insns[t].src_reg == BPF_PSEUDO_CALL) {
			init_explored_state(env, t);
			ret = push_insn(t, t + insns[t].imm + 1, BRANCH,
					env, false);
		}
		return ret;

	case BPF_JA:
		if (BPF_SRC(insns[t].code) != BPF_K)
			return -EINVAL;

		/* unconditional jump with single edge */
		ret = push_insn(t, t + insns[t].off + 1, FALLTHROUGH, env,
				true);
		if (ret)
			return ret;

		/* unconditional jmp is not a good pruning point,
		 * but it's marked, since backtracking needs
		 * to record jmp history in is_state_visited().
		 */
		init_explored_state(env, t + insns[t].off + 1);
		/* tell verifier to check for equivalent states
		 * after every call and jump
		 */
		if (t + 1 < insn_cnt)
			init_explored_state(env, t + 1);

		return ret;

	default:
		/* conditional jump with two edges */
		init_explored_state(env, t);
		ret = push_insn(t, t + 1, FALLTHROUGH, env, true);
		if (ret)
			return ret;

		return push_insn(t, t + insns[t].off + 1, BRANCH, env, true);
	}
}

Project: linux
File: syscall.c

static void bpf_raw_tp_link_dealloc(struct bpf_link *link)
{
	struct bpf_raw_tp_link *raw_tp =
		container_of(link, struct bpf_raw_tp_link, link);

	kfree(raw_tp);
}

Project: linux
File: syscall.c

static int bpf_raw_tracepoint_open(const union bpf_attr *attr)
{
	struct bpf_link_primer link_primer;
	struct bpf_raw_tp_link *link;
	struct bpf_raw_event_map *btp;
	struct bpf_prog *prog;
	const char *tp_name;
	char buf[128];
	int err;

	if (CHECK_ATTR(BPF_RAW_TRACEPOINT_OPEN))
		return -EINVAL;

	prog = bpf_prog_get(attr->raw_tracepoint.prog_fd);
	if (IS_ERR(prog))
		return PTR_ERR(prog);

	switch (prog->type) {
	case BPF_PROG_TYPE_TRACING:
	case BPF_PROG_TYPE_EXT:
	case BPF_PROG_TYPE_LSM:
		if (attr->raw_tracepoint.name) {
			/* The attach point for this category of programs
			 * should be specified via btf_id during program load.
			 */
			err = -EINVAL;
			goto out_put_prog;
		}
		if (prog->type == BPF_PROG_TYPE_TRACING &&
		    prog->expected_attach_type == BPF_TRACE_RAW_TP) {
			tp_name = prog->aux->attach_func_name;
			break;
		}
		err = bpf_tracing_prog_attach(prog, 0, 0);
		if (err >= 0)
			return err;
		goto out_put_prog;
	case BPF_PROG_TYPE_RAW_TRACEPOINT:
	case BPF_PROG_TYPE_RAW_TRACEPOINT_WRITABLE:
		if (strncpy_from_user(buf,
				      u64_to_user_ptr(attr->raw_tracepoint.name),
				      sizeof(buf) - 1) < 0) {
			err = -EFAULT;
			goto out_put_prog;
		}
		buf[sizeof(buf) - 1] = 0;
		tp_name = buf;
		break;
	default:
		err = -EINVAL;
		goto out_put_prog;
	}

	btp = bpf_get_raw_tracepoint(tp_name);
	if (!btp) {
		err = -ENOENT;
		goto out_put_prog;
	}

	link = kzalloc(sizeof(*link), GFP_USER);
	if (!link) {
		err = -ENOMEM;
		goto out_put_btp;
	}
	bpf_link_init(&link->link, BPF_LINK_TYPE_RAW_TRACEPOINT,
		      &bpf_raw_tp_link_lops, prog);
	link->btp = btp;

	err = bpf_link_prime(&link->link, &link_primer);
	if (err) {
		kfree(link);
		goto out_put_btp;
	}

	err = bpf_probe_register(link->btp, prog);
	if (err) {
		bpf_link_cleanup(&link_primer);
		goto out_put_btp;
	}

	return bpf_link_settle(&link_primer);

out_put_btp:
	bpf_put_raw_tracepoint(btp);
out_put_prog:
	bpf_prog_put(prog);
	return err;
}

Project: linux
File: syscall.c

static int bpf_obj_get(const union bpf_attr *attr)
{
	if (CHECK_ATTR(BPF_OBJ) || attr->bpf_fd != 0 ||
	    attr->file_flags & ~BPF_OBJ_FLAG_MASK)
		return -EINVAL;

	return bpf_obj_get_user(u64_to_user_ptr(attr->pathname),
				attr->file_flags);
}

Project: linux
File: syscall.c

static int bpf_map_update_value(struct bpf_map *map, struct fd f, void *key,
				void *value, __u64 flags)
{
	int err;

	/* Need to create a kthread, thus must support schedule */
	if (bpf_map_is_dev_bound(map)) {
		return bpf_map_offload_update_elem(map, key, value, flags);
	} else if (map->map_type == BPF_MAP_TYPE_CPUMAP ||
		   map->map_type == BPF_MAP_TYPE_STRUCT_OPS) {
		return map->ops->map_update_elem(map, key, value, flags);
	} else if (map->map_type == BPF_MAP_TYPE_SOCKHASH ||
		   map->map_type == BPF_MAP_TYPE_SOCKMAP) {
		return sock_map_update_elem_sys(map, key, value, flags);
	} else if (IS_FD_PROG_ARRAY(map)) {
		return bpf_fd_array_map_update_elem(map, f.file, key, value,
						    flags);
	}

	bpf_disable_instrumentation();
	if (map->map_type == BPF_MAP_TYPE_PERCPU_HASH ||
	    map->map_type == BPF_MAP_TYPE_LRU_PERCPU_HASH) {
		err = bpf_percpu_hash_update(map, key, value, flags);
	} else if (map->map_type == BPF_MAP_TYPE_PERCPU_ARRAY) {
		err = bpf_percpu_array_update(map, key, value, flags);
	} else if (map->map_type == BPF_MAP_TYPE_PERCPU_CGROUP_STORAGE) {
		err = bpf_percpu_cgroup_storage_update(map, key, value,
						       flags);
	} else if (IS_FD_ARRAY(map)) {
		rcu_read_lock();
		err = bpf_fd_array_map_update_elem(map, f.file, key, value,
						   flags);
		rcu_read_unlock();
	} else if (map->map_type == BPF_MAP_TYPE_HASH_OF_MAPS) {
		rcu_read_lock();
		err = bpf_fd_htab_map_update_elem(map, f.file, key, value,
						  flags);
		rcu_read_unlock();
	} else if (map->map_type == BPF_MAP_TYPE_REUSEPORT_SOCKARRAY) {
		/* rcu_read_lock() is not needed */
		err = bpf_fd_reuseport_array_update_elem(map, key, value,
							 flags);
	} else if (map->map_type == BPF_MAP_TYPE_QUEUE ||
		   map->map_type == BPF_MAP_TYPE_STACK) {
		err = map->ops->map_push_elem(map, value, flags);
	} else {
		rcu_read_lock();
		err = map->ops->map_update_elem(map, key, value, flags);
		rcu_read_unlock();
	}
	bpf_enable_instrumentation();
	maybe_wait_bpf_programs(map);

	return err;
}

Project: linux
File: verifier.c

static int jit_subprogs(struct bpf_verifier_env *env)
{
	struct bpf_prog *prog = env->prog, **func, *tmp;
	int i, j, subprog_start, subprog_end = 0, len, subprog;
	struct bpf_map *map_ptr;
	struct bpf_insn *insn;
	void *old_bpf_func;
	int err, num_exentries;

	if (env->subprog_cnt <= 1)
		return 0;

	for (i = 0, insn = prog->insnsi; i < prog->len; i++, insn++) {
		if (!bpf_pseudo_call(insn))
			continue;
		/* Upon error here we cannot fall back to interpreter but
		 * need a hard reject of the program. Thus -EFAULT is
		 * propagated in any case.
		 */
		subprog = find_subprog(env, i + insn->imm + 1);
		if (subprog < 0) {
			WARN_ONCE(1, "verifier bug. No program starts at insn %d\n",
				  i + insn->imm + 1);
			return -EFAULT;
		}
		/* temporarily remember subprog id inside insn instead of
		 * aux_data, since next loop will split up all insns into funcs
		 */
		insn->off = subprog;
		/* remember original imm in case JIT fails and fallback
		 * to interpreter will be needed
		 */
		env->insn_aux_data[i].call_imm = insn->imm;
		/* point imm to __bpf_call_base+1 from JITs point of view */
		insn->imm = 1;
	}

	err = bpf_prog_alloc_jited_linfo(prog);
	if (err)
		goto out_undo_insn;

	err = -ENOMEM;
	func = kcalloc(env->subprog_cnt, sizeof(prog), GFP_KERNEL);
	if (!func)
		goto out_undo_insn;

	for (i = 0; i < env->subprog_cnt; i++) {
		subprog_start = subprog_end;
		subprog_end = env->subprog_info[i + 1].start;

		len = subprog_end - subprog_start;
		/* BPF_PROG_RUN doesn't call subprogs directly,
		 * hence main prog stats include the runtime of subprogs.
		 * subprogs don't have IDs and not reachable via prog_get_next_id
		 * func[i]->stats will never be accessed and stays NULL
		 */
		func[i] = bpf_prog_alloc_no_stats(bpf_prog_size(len), GFP_USER);
		if (!func[i])
			goto out_free;
		memcpy(func[i]->insnsi, &prog->insnsi[subprog_start],
		       len * sizeof(struct bpf_insn));
		func[i]->type = prog->type;
		func[i]->len = len;
		if (bpf_prog_calc_tag(func[i]))
			goto out_free;
		func[i]->is_func = 1;
		func[i]->aux->func_idx = i;
		/* the btf and func_info will be freed only at prog->aux */
		func[i]->aux->btf = prog->aux->btf;
		func[i]->aux->func_info = prog->aux->func_info;

		for (j = 0; j < prog->aux->size_poke_tab; j++) {
			u32 insn_idx = prog->aux->poke_tab[j].insn_idx;
			int ret;

			if (!(insn_idx >= subprog_start &&
			      insn_idx <= subprog_end))
				continue;

			ret = bpf_jit_add_poke_descriptor(func[i],
							  &prog->aux->poke_tab[j]);
			if (ret < 0) {
				verbose(env, "adding tail call poke descriptor failed\n");
				goto out_free;
			}

			func[i]->insnsi[insn_idx - subprog_start].imm = ret + 1;

			map_ptr = func[i]->aux->poke_tab[ret].tail_call.map;
			ret = map_ptr->ops->map_poke_track(map_ptr, func[i]->aux);
			if (ret < 0) {
				verbose(env, "tracking tail call prog failed\n");
				goto out_free;
			}
		}

		/* Use bpf_prog_F_tag to indicate functions in stack traces.
		 * Long term would need debug info to populate names
		 */
		func[i]->aux->name[0] = 'F';
		func[i]->aux->stack_depth = env->subprog_info[i].stack_depth;
		func[i]->jit_requested = 1;
		func[i]->aux->linfo = prog->aux->linfo;
		func[i]->aux->nr_linfo = prog->aux->nr_linfo;
		func[i]->aux->jited_linfo = prog->aux->jited_linfo;
		func[i]->aux->linfo_idx = env->subprog_info[i].linfo_idx;
		num_exentries = 0;
		insn = func[i]->insnsi;
		for (j = 0; j < func[i]->len; j++, insn++) {
			if (BPF_CLASS(insn->code) == BPF_LDX &&
			    BPF_MODE(insn->code) == BPF_PROBE_MEM)
				num_exentries++;
		}
		func[i]->aux->num_exentries = num_exentries;
		func[i]->aux->tail_call_reachable = env->subprog_info[i].tail_call_reachable;
		func[i] = bpf_int_jit_compile(func[i]);
		if (!func[i]->jited) {
			err = -ENOTSUPP;
			goto out_free;
		}
		cond_resched();
	}

	/* Untrack main program's aux structs so that during map_poke_run()
	 * we will not stumble upon the unfilled poke descriptors; each
	 * of the main program's poke descs got distributed across subprogs
	 * and got tracked onto map, so we are sure that none of them will
	 * be missed after the operation below
	 */
	for (i = 0; i < prog->aux->size_poke_tab; i++) {
		map_ptr = prog->aux->poke_tab[i].tail_call.map;

		map_ptr->ops->map_poke_untrack(map_ptr, prog->aux);
	}

	/* at this point all bpf functions were successfully JITed
	 * now populate all bpf_calls with correct addresses and
	 * run last pass of JIT
	 */
	for (i = 0; i < env->subprog_cnt; i++) {
		insn = func[i]->insnsi;
		for (j = 0; j < func[i]->len; j++, insn++) {
			if (!bpf_pseudo_call(insn))
				continue;
			subprog = insn->off;
			insn->imm = BPF_CAST_CALL(func[subprog]->bpf_func) -
				    __bpf_call_base;
		}

		/* we use the aux data to keep a list of the start addresses
		 * of the JITed images for each function in the program
		 *
		 * for some architectures, such as powerpc64, the imm field
		 * might not be large enough to hold the offset of the start
		 * address of the callee's JITed image from __bpf_call_base
		 *
		 * in such cases, we can lookup the start address of a callee
		 * by using its subprog id, available from the off field of
		 * the call instruction, as an index for this list
		 */
		func[i]->aux->func = func;
		func[i]->aux->func_cnt = env->subprog_cnt;
	}
	for (i = 0; i < env->subprog_cnt; i++) {
		old_bpf_func = func[i]->bpf_func;
		tmp = bpf_int_jit_compile(func[i]);
		if (tmp != func[i] || func[i]->bpf_func != old_bpf_func) {
			verbose(env, "JIT doesn't support bpf-to-bpf calls\n");
			err = -ENOTSUPP;
			goto out_free;
		}
		cond_resched();
	}

	/* finally lock prog and jit images for all functions and
	 * populate kallsysm
	 */
	for (i = 0; i < env->subprog_cnt; i++) {
		bpf_prog_lock_ro(func[i]);
		bpf_prog_kallsyms_add(func[i]);
	}

	/* Last step: make now unused interpreter insns from main
	 * prog consistent for later dump requests, so they can
	 * later look the same as if they were interpreted only.
	 */
	for (i = 0, insn = prog->insnsi; i < prog->len; i++, insn++) {
		if (!bpf_pseudo_call(insn))
			continue;
		insn->off = env->insn_aux_data[i].call_imm;
		subprog = find_subprog(env, i + insn->off + 1);
		insn->imm = subprog;
	}

	prog->jited = 1;
	prog->bpf_func = func[0]->bpf_func;
	prog->aux->func = func;
	prog->aux->func_cnt = env->subprog_cnt;
	bpf_prog_free_unused_jited_linfo(prog);
	return 0;
out_free:
	for (i = 0; i < env->subprog_cnt; i++) {
		if (!func[i])
			continue;

		for (j = 0; j < func[i]->aux->size_poke_tab; j++) {
			map_ptr = func[i]->aux->poke_tab[j].tail_call.map;
			map_ptr->ops->map_poke_untrack(map_ptr, func[i]->aux);
		}
		bpf_jit_free(func[i]);
	}
	kfree(func);
out_undo_insn:
	/* cleanup main prog to be interpreted */
	prog->jit_requested = 0;
	for (i = 0, insn = prog->insnsi; i < prog->len; i++, insn++) {
		if (!bpf_pseudo_call(insn))
			continue;
		insn->off = 0;
		insn->imm = env->insn_aux_data[i].call_imm;
	}
	bpf_prog_free_jited_linfo(prog);
	return err;
}

Project: linux
File: syscall.c

static int bpf_prog_query(const union bpf_attr *attr,
			  union bpf_attr __user *uattr)
{
	if (!capable(CAP_NET_ADMIN))
		return -EPERM;
	if (CHECK_ATTR(BPF_PROG_QUERY))
		return -EINVAL;
	if (attr->query.query_flags & ~BPF_F_QUERY_EFFECTIVE)
		return -EINVAL;

	switch (attr->query.attach_type) {
	case BPF_CGROUP_INET_INGRESS:
	case BPF_CGROUP_INET_EGRESS:
	case BPF_CGROUP_INET_SOCK_CREATE:
	case BPF_CGROUP_INET_SOCK_RELEASE:
	case BPF_CGROUP_INET4_BIND:
	case BPF_CGROUP_INET6_BIND:
	case BPF_CGROUP_INET4_POST_BIND:
	case BPF_CGROUP_INET6_POST_BIND:
	case BPF_CGROUP_INET4_CONNECT:
	case BPF_CGROUP_INET6_CONNECT:
	case BPF_CGROUP_INET4_GETPEERNAME:
	case BPF_CGROUP_INET6_GETPEERNAME:
	case BPF_CGROUP_INET4_GETSOCKNAME:
	case BPF_CGROUP_INET6_GETSOCKNAME:
	case BPF_CGROUP_UDP4_SENDMSG:
	case BPF_CGROUP_UDP6_SENDMSG:
	case BPF_CGROUP_UDP4_RECVMSG:
	case BPF_CGROUP_UDP6_RECVMSG:
	case BPF_CGROUP_SOCK_OPS:
	case BPF_CGROUP_DEVICE:
	case BPF_CGROUP_SYSCTL:
	case BPF_CGROUP_GETSOCKOPT:
	case BPF_CGROUP_SETSOCKOPT:
		return cgroup_bpf_prog_query(attr, uattr);
	case BPF_LIRC_MODE2:
		return lirc_prog_query(attr, uattr);
	case BPF_FLOW_DISSECTOR:
	case BPF_SK_LOOKUP:
		return netns_bpf_prog_query(attr, uattr);
	default:
		return -EINVAL;
	}
}

Project: linux
File: syscall.c

static int bpf_map_mmap(struct file *filp, struct vm_area_struct *vma)
{
	struct bpf_map *map = filp->private_data;
	int err;

	if (!map->ops->map_mmap || map_value_has_spin_lock(map))
		return -ENOTSUPP;

	if (!(vma->vm_flags & VM_SHARED))
		return -EINVAL;

	mutex_lock(&map->freeze_mutex);

	if (vma->vm_flags & VM_WRITE) {
		if (map->frozen) {
			err = -EPERM;
			goto out;
		}
		/* map is meant to be read-only, so do not allow mapping as
		 * writable, because it's possible to leak a writable page
		 * reference and allows user-space to still modify it after
		 * freezing, while verifier will assume contents do not change
		 */
		if (map->map_flags & BPF_F_RDONLY_PROG) {
			err = -EACCES;
			goto out;
		}
	}

	/* set default open/close callbacks */
	vma->vm_ops = &bpf_map_default_vmops;
	vma->vm_private_data = map;
	vma->vm_flags &= ~VM_MAYEXEC;
	if (!(vma->vm_flags & VM_WRITE))
		/* disallow re-mapping with PROT_WRITE */
		vma->vm_flags &= ~VM_MAYWRITE;

	err = map->ops->map_mmap(map, vma);
	if (err)
		goto out;

	if (vma->vm_flags & VM_MAYWRITE)
		map->writecnt++;
out:
	mutex_unlock(&map->freeze_mutex);
	return err;
}

Project: linux
File: verifier.c

static int fixup_call_args(struct bpf_verifier_env *env)
{
#ifndef CONFIG_BPF_JIT_ALWAYS_ON
	struct bpf_prog *prog = env->prog;
	struct bpf_insn *insn = prog->insnsi;
	int i, depth;
#endif
	int err = 0;

	if (env->prog->jit_requested &&
	    !bpf_prog_is_dev_bound(env->prog->aux)) {
		err = jit_subprogs(env);
		if (err == 0)
			return 0;
		if (err == -EFAULT)
			return err;
	}
#ifndef CONFIG_BPF_JIT_ALWAYS_ON
	if (env->subprog_cnt > 1 && env->prog->aux->tail_call_reachable) {
		/* When JIT fails the progs with bpf2bpf calls and tail_calls
		 * have to be rejected, since interpreter doesn't support them yet.
		 */
		verbose(env, "tail_calls are not allowed in non-JITed programs with bpf-to-bpf calls\n");
		return -EINVAL;
	}
	for (i = 0; i < prog->len; i++, insn++) {
		if (!bpf_pseudo_call(insn))
			continue;
		depth = get_callee_stack_depth(env, insn, i);
		if (depth < 0)
			return depth;
		bpf_patch_call_args(insn, depth);
	}
	err = 0;
#endif
	return err;
}

Project: linux
File: syscall.c

int bpf_map_new_fd(struct bpf_map *map, int flags)
{
	int ret;

	ret = security_bpf_map(map, OPEN_FMODE(flags));
	if (ret < 0)
		return ret;

	return anon_inode_getfd("bpf-map", &bpf_map_fops, map,
				flags | O_CLOEXEC);
}

Project: linux
File: syscall.c

static void bpf_map_put_uref(struct bpf_map *map)
{
	if (atomic64_dec_and_test(&map->usercnt)) {
		if (map->ops->map_release_uref)
			map->ops->map_release_uref(map);
	}
}

Project: linux
File: syscall.c

void bpf_prog_put(struct bpf_prog *prog)
{
	__bpf_prog_put(prog, true);
}

Project: linux
File: syscall.c

static int bpf_tracing_link_fill_link_info(const struct bpf_link *link,
					   struct bpf_link_info *info)
{
	struct bpf_tracing_link *tr_link =
		container_of(link, struct bpf_tracing_link, link);

	info->tracing.attach_type = tr_link->attach_type;

	return 0;
}

Project: linux
File: verifier.c

static int do_check(struct bpf_verifier_env *env)
{
	bool pop_log = !(env->log.level & BPF_LOG_LEVEL2);
	struct bpf_verifier_state *state = env->cur_state;
	struct bpf_insn *insns = env->prog->insnsi;
	struct bpf_reg_state *regs;
	int insn_cnt = env->prog->len;
	bool do_print_state = false;
	int prev_insn_idx = -1;

	for (;;) {
		struct bpf_insn *insn;
		u8 class;
		int err;

		env->prev_insn_idx = prev_insn_idx;
		if (env->insn_idx >= insn_cnt) {
			verbose(env, "invalid insn idx %d insn_cnt %d\n",
				env->insn_idx, insn_cnt);
			return -EFAULT;
		}

		insn = &insns[env->insn_idx];
		class = BPF_CLASS(insn->code);

		if (++env->insn_processed > BPF_COMPLEXITY_LIMIT_INSNS) {
			verbose(env,
				"BPF program is too large. Processed %d insn\n",
				env->insn_processed);
			return -E2BIG;
		}

		err = is_state_visited(env, env->insn_idx);
		if (err < 0)
			return err;
		if (err == 1) {
			/* found equivalent state, can prune the search */
			if (env->log.level & BPF_LOG_LEVEL) {
				if (do_print_state)
					verbose(env, "\nfrom %d to %d%s: safe\n",
						env->prev_insn_idx, env->insn_idx,
						env->cur_state->speculative ?
						" (speculative execution)" : "");
				else
					verbose(env, "%d: safe\n", env->insn_idx);
			}
			goto process_bpf_exit;
		}

		if (signal_pending(current))
			return -EAGAIN;

		if (need_resched())
			cond_resched();

		if (env->log.level & BPF_LOG_LEVEL2 ||
		    (env->log.level & BPF_LOG_LEVEL && do_print_state)) {
			if (env->log.level & BPF_LOG_LEVEL2)
				verbose(env, "%d:", env->insn_idx);
			else
				verbose(env, "\nfrom %d to %d%s:",
					env->prev_insn_idx, env->insn_idx,
					env->cur_state->speculative ?
					" (speculative execution)" : "");
			print_verifier_state(env, state->frame[state->curframe]);
			do_print_state = false;
		}

		if (env->log.level & BPF_LOG_LEVEL) {
			const struct bpf_insn_cbs cbs = {
				.cb_print	= verbose,
				.private_data	= env,
			};

			verbose_linfo(env, env->insn_idx, "; ");
			verbose(env, "%d: ", env->insn_idx);
			print_bpf_insn(&cbs, insn, env->allow_ptr_leaks);
		}

		if (bpf_prog_is_dev_bound(env->prog->aux)) {
			err = bpf_prog_offload_verify_insn(env, env->insn_idx,
							   env->prev_insn_idx);
			if (err)
				return err;
		}

		regs = cur_regs(env);
		env->insn_aux_data[env->insn_idx].seen = env->pass_cnt;
		prev_insn_idx = env->insn_idx;

		if (class == BPF_ALU || class == BPF_ALU64) {
			err = check_alu_op(env, insn);
			if (err)
				return err;

		} else if (class == BPF_LDX) {
			enum bpf_reg_type *prev_src_type, src_reg_type;

			/* check for reserved fields is already done */

			/* check src operand */
			err = check_reg_arg(env, insn->src_reg, SRC_OP);
			if (err)
				return err;

			err = check_reg_arg(env, insn->dst_reg, DST_OP_NO_MARK);
			if (err)
				return err;

			src_reg_type = regs[insn->src_reg].type;

			/* check that memory (src_reg + off) is readable,
			 * the state of dst_reg will be updated by this func
			 */
			err = check_mem_access(env, env->insn_idx, insn->src_reg,
					       insn->off, BPF_SIZE(insn->code),
					       BPF_READ, insn->dst_reg, false);
			if (err)
				return err;

			prev_src_type = &env->insn_aux_data[env->insn_idx].ptr_type;

			if (*prev_src_type == NOT_INIT) {
				/* saw a valid insn
				 * dst_reg = *(u32 *)(src_reg + off)
				 * save type to validate intersecting paths
				 */
				*prev_src_type = src_reg_type;

			} else if (reg_type_mismatch(src_reg_type, *prev_src_type)) {
				/* ABuser program is trying to use the same insn
				 * dst_reg = *(u32*) (src_reg + off)
				 * with different pointer types:
				 * src_reg == ctx in one branch and
				 * src_reg == stack|map in some other branch.
				 * Reject it.
				 */
				verbose(env, "same insn cannot be used with different pointers\n");
				return -EINVAL;
			}

		} else if (class == BPF_STX) {
			enum bpf_reg_type *prev_dst_type, dst_reg_type;

			if (BPF_MODE(insn->code) == BPF_ATOMIC) {
				err = check_atomic(env, env->insn_idx, insn);
				if (err)
					return err;
				env->insn_idx++;
				continue;
			}

			if (BPF_MODE(insn->code) != BPF_MEM || insn->imm != 0) {
				verbose(env, "BPF_STX uses reserved fields\n");
				return -EINVAL;
			}

			/* check src1 operand */
			err = check_reg_arg(env, insn->src_reg, SRC_OP);
			if (err)
				return err;
			/* check src2 operand */
			err = check_reg_arg(env, insn->dst_reg, SRC_OP);
			if (err)
				return err;

			dst_reg_type = regs[insn->dst_reg].type;

			/* check that memory (dst_reg + off) is writeable */
			err = check_mem_access(env, env->insn_idx, insn->dst_reg,
					       insn->off, BPF_SIZE(insn->code),
					       BPF_WRITE, insn->src_reg, false);
			if (err)
				return err;

			prev_dst_type = &env->insn_aux_data[env->insn_idx].ptr_type;

			if (*prev_dst_type == NOT_INIT) {
				*prev_dst_type = dst_reg_type;
			} else if (reg_type_mismatch(dst_reg_type, *prev_dst_type)) {
				verbose(env, "same insn cannot be used with different pointers\n");
				return -EINVAL;
			}

		} else if (class == BPF_ST) {
			if (BPF_MODE(insn->code) != BPF_MEM ||
			    insn->src_reg != BPF_REG_0) {
				verbose(env, "BPF_ST uses reserved fields\n");
				return -EINVAL;
			}
			/* check src operand */
			err = check_reg_arg(env, insn->dst_reg, SRC_OP);
			if (err)
				return err;

			if (is_ctx_reg(env, insn->dst_reg)) {
				verbose(env, "BPF_ST stores into R%d %s is not allowed\n",
					insn->dst_reg,
					reg_type_str[reg_state(env, insn->dst_reg)->type]);
				return -EACCES;
			}

			/* check that memory (dst_reg + off) is writeable */
			err = check_mem_access(env, env->insn_idx, insn->dst_reg,
					       insn->off, BPF_SIZE(insn->code),
					       BPF_WRITE, -1, false);
			if (err)
				return err;

		} else if (class == BPF_JMP || class == BPF_JMP32) {
			u8 opcode = BPF_OP(insn->code);

			env->jmps_processed++;
			if (opcode == BPF_CALL) {
				if (BPF_SRC(insn->code) != BPF_K ||
				    insn->off != 0 ||
				    (insn->src_reg != BPF_REG_0 &&
				     insn->src_reg != BPF_PSEUDO_CALL) ||
				    insn->dst_reg != BPF_REG_0 ||
				    class == BPF_JMP32) {
					verbose(env, "BPF_CALL uses reserved fields\n");
					return -EINVAL;
				}

				if (env->cur_state->active_spin_lock &&
				    (insn->src_reg == BPF_PSEUDO_CALL ||
				     insn->imm != BPF_FUNC_spin_unlock)) {
					verbose(env, "function calls are not allowed while holding a lock\n");
					return -EINVAL;
				}
				if (insn->src_reg == BPF_PSEUDO_CALL)
					err = check_func_call(env, insn, &env->insn_idx);
				else
					err = check_helper_call(env, insn->imm, env->insn_idx);
				if (err)
					return err;

			} else if (opcode == BPF_JA) {
				if (BPF_SRC(insn->code) != BPF_K ||
				    insn->imm != 0 ||
				    insn->src_reg != BPF_REG_0 ||
				    insn->dst_reg != BPF_REG_0 ||
				    class == BPF_JMP32) {
					verbose(env, "BPF_JA uses reserved fields\n");
					return -EINVAL;
				}

				env->insn_idx += insn->off + 1;
				continue;

			} else if (opcode == BPF_EXIT) {
				if (BPF_SRC(insn->code) != BPF_K ||
				    insn->imm != 0 ||
				    insn->src_reg != BPF_REG_0 ||
				    insn->dst_reg != BPF_REG_0 ||
				    class == BPF_JMP32) {
					verbose(env, "BPF_EXIT uses reserved fields\n");
					return -EINVAL;
				}

				if (env->cur_state->active_spin_lock) {
					verbose(env, "bpf_spin_unlock is missing\n");
					return -EINVAL;
				}

				if (state->curframe) {
					/* exit from nested function */
					err = prepare_func_exit(env, &env->insn_idx);
					if (err)
						return err;
					do_print_state = true;
					continue;
				}

				err = check_reference_leak(env);
				if (err)
					return err;

				err = check_return_code(env);
				if (err)
					return err;
process_bpf_exit:
				update_branch_counts(env, env->cur_state);
				err = pop_stack(env, &prev_insn_idx,
						&env->insn_idx, pop_log);
				if (err < 0) {
					if (err != -ENOENT)
						return err;
					break;
				} else {
					do_print_state = true;
					continue;
				}
			} else {
				err = check_cond_jmp_op(env, insn, &env->insn_idx);
				if (err)
					return err;
			}
		} else if (class == BPF_LD) {
			u8 mode = BPF_MODE(insn->code);

			if (mode == BPF_ABS || mode == BPF_IND) {
				err = check_ld_abs(env, insn);
				if (err)
					return err;

			} else if (mode == BPF_IMM) {
				err = check_ld_imm(env, insn);
				if (err)
					return err;

				env->insn_idx++;
				env->insn_aux_data[env->insn_idx].seen = env->pass_cnt;
			} else {
				verbose(env, "invalid BPF_LD mode\n");
				return -EINVAL;
			}
		} else {
			verbose(env, "unknown insn class %d\n", class);
			return -EINVAL;
		}

		env->insn_idx++;
	}

	return 0;
}

Project: linux
File: verifier.c

static void do_refine_retval_range(struct bpf_reg_state *regs, int ret_type,
				   int func_id,
				   struct bpf_call_arg_meta *meta)
{
	struct bpf_reg_state *ret_reg = &regs[BPF_REG_0];

	if (ret_type != RET_INTEGER ||
	    (func_id != BPF_FUNC_get_stack &&
	     func_id != BPF_FUNC_probe_read_str &&
	     func_id != BPF_FUNC_probe_read_kernel_str &&
	     func_id != BPF_FUNC_probe_read_user_str))
		return;

	ret_reg->smax_value = meta->msize_max_value;
	ret_reg->s32_max_value = meta->msize_max_value;
	ret_reg->smin_value = -MAX_ERRNO;
	ret_reg->s32_min_value = -MAX_ERRNO;
	__reg_deduce_bounds(ret_reg);
	__reg_bound_offset(ret_reg);
	__update_reg_bounds(ret_reg);
}

Project: linux
File: syscall.c

static fmode_t map_get_sys_perms(struct bpf_map *map, struct fd f)
{
	fmode_t mode = f.file->f_mode;

	/* Our file permissions may have been overridden by global
	 * map permissions facing syscall side.
	 */
	if (READ_ONCE(map->frozen))
		mode &= ~FMODE_CAN_WRITE;
	return mode;
}

Project: linux
File: syscall.c

static int bpf_prog_get_fd_by_id(const union bpf_attr *attr)
{
	struct bpf_prog *prog;
	u32 id = attr->prog_id;
	int fd;

	if (CHECK_ATTR(BPF_PROG_GET_FD_BY_ID))
		return -EINVAL;

	if (!capable(CAP_SYS_ADMIN))
		return -EPERM;

	prog = bpf_prog_by_id(id);
	if (IS_ERR(prog))
		return PTR_ERR(prog);

	fd = bpf_prog_new_fd(prog);
	if (fd < 0)
		bpf_prog_put(prog);

	return fd;
}

Project: linux
File: syscall.c

static int map_freeze(const union bpf_attr *attr)
{
	int err = 0, ufd = attr->map_fd;
	struct bpf_map *map;
	struct fd f;

	if (CHECK_ATTR(BPF_MAP_FREEZE))
		return -EINVAL;

	f = fdget(ufd);
	map = __bpf_map_get(f);
	if (IS_ERR(map))
		return PTR_ERR(map);

	if (map->map_type == BPF_MAP_TYPE_STRUCT_OPS) {
		fdput(f);
		return -ENOTSUPP;
	}

	mutex_lock(&map->freeze_mutex);

	if (map->writecnt) {
		err = -EBUSY;
		goto err_put;
	}
	if (READ_ONCE(map->frozen)) {
		err = -EBUSY;
		goto err_put;
	}
	if (!bpf_capable()) {
		err = -EPERM;
		goto err_put;
	}

	WRITE_ONCE(map->frozen, true);
err_put:
	mutex_unlock(&map->freeze_mutex);
	fdput(f);
	return err;
}

Project: linux
File: syscall.c

void *bpf_map_area_alloc(u64 size, int numa_node)
{
	return __bpf_map_area_alloc(size, numa_node, false);
}

Project: linux
File: verifier.c

static int check_subprogs(struct bpf_verifier_env *env)
{
	int i, ret, subprog_start, subprog_end, off, cur_subprog = 0;
	struct bpf_subprog_info *subprog = env->subprog_info;
	struct bpf_insn *insn = env->prog->insnsi;
	int insn_cnt = env->prog->len;

	/* Add entry function. */
	ret = add_subprog(env, 0);
	if (ret < 0)
		return ret;

	/* determine subprog starts. The end is one before the next starts */
	for (i = 0; i < insn_cnt; i++) {
		if (!bpf_pseudo_call(insn + i))
			continue;
		if (!env->bpf_capable) {
			verbose(env,
				"function calls to other bpf functions are allowed for CAP_BPF and CAP_SYS_ADMIN\n");
			return -EPERM;
		}
		ret = add_subprog(env, i + insn[i].imm + 1);
		if (ret < 0)
			return ret;
	}

	/* Add a fake 'exit' subprog which could simplify subprog iteration
	 * logic. 'subprog_cnt' should not be increased.
	 */
	subprog[env->subprog_cnt].start = insn_cnt;

	if (env->log.level & BPF_LOG_LEVEL2)
		for (i = 0; i < env->subprog_cnt; i++)
			verbose(env, "func#%d @%d\n", i, subprog[i].start);

	/* now check that all jumps are within the same subprog */
	subprog_start = subprog[cur_subprog].start;
	subprog_end = subprog[cur_subprog + 1].start;
	for (i = 0; i < insn_cnt; i++) {
		u8 code = insn[i].code;

		if (code == (BPF_JMP | BPF_CALL) &&
		    insn[i].imm == BPF_FUNC_tail_call &&
		    insn[i].src_reg != BPF_PSEUDO_CALL)
			subprog[cur_subprog].has_tail_call = true;
		if (BPF_CLASS(code) == BPF_LD &&
		    (BPF_MODE(code) == BPF_ABS || BPF_MODE(code) == BPF_IND))
			subprog[cur_subprog].has_ld_abs = true;
		if (BPF_CLASS(code) != BPF_JMP && BPF_CLASS(code) != BPF_JMP32)
			goto next;
		if (BPF_OP(code) == BPF_EXIT || BPF_OP(code) == BPF_CALL)
			goto next;
		off = i + insn[i].off + 1;
		if (off < subprog_start || off >= subprog_end) {
			verbose(env, "jump out of range from insn %d to %d\n", i, off);
			return -EINVAL;
		}
next:
		if (i == subprog_end - 1) {
			/* to avoid fall-through from one subprog into another
			 * the last insn of the subprog should be either exit
			 * or unconditional jump back
			 */
			if (code != (BPF_JMP | BPF_EXIT) &&
			    code != (BPF_JMP | BPF_JA)) {
				verbose(env, "last insn is not an exit or jmp\n");
				return -EINVAL;
			}
			subprog_start = subprog_end;
			cur_subprog++;
			if (cur_subprog < env->subprog_cnt)
				subprog_end = subprog[cur_subprog + 1].start;
		}
	}
	return 0;
}

Project: linux
File: syscall.c

struct bpf_prog *bpf_prog_get(u32 ufd)
{
	return __bpf_prog_get(ufd, NULL, false);
}

Project: linux
File: syscall.c

static void maybe_wait_bpf_programs(struct bpf_map *map)
{
	/* Wait for any running BPF programs to complete so that
	 * userspace, when we return to it, knows that all programs
	 * that could be running use the new map value.
	 */
	if (map->map_type == BPF_MAP_TYPE_HASH_OF_MAPS ||
	    map->map_type == BPF_MAP_TYPE_ARRAY_OF_MAPS)
		synchronize_rcu();
}

Project: linux
File: syscall.c

static int bpf_obj_get_info_by_fd(const union bpf_attr *attr,
				  union bpf_attr __user *uattr)
{
	int ufd = attr->info.bpf_fd;
	struct fd f;
	int err;

	if (CHECK_ATTR(BPF_OBJ_GET_INFO_BY_FD))
		return -EINVAL;

	f = fdget(ufd);
	if (!f.file)
		return -EBADFD;

	if (f.file->f_op == &bpf_prog_fops)
		err = bpf_prog_get_info_by_fd(f.file, f.file->private_data, attr,
					      uattr);
	else if (f.file->f_op == &bpf_map_fops)
		err = bpf_map_get_info_by_fd(f.file, f.file->private_data, attr,
					     uattr);
	else if (f.file->f_op == &btf_fops)
		err = bpf_btf_get_info_by_fd(f.file, f.file->private_data, attr, uattr);
	else if (f.file->f_op == &bpf_link_fops)
		err = bpf_link_get_info_by_fd(f.file, f.file->private_data,
					      attr, uattr);
	else
		err = -EINVAL;

	fdput(f);
	return err;
}

Project: linux
File: syscall.c

static bool is_perfmon_prog_type(enum bpf_prog_type prog_type)
{
	switch (prog_type) {
	case BPF_PROG_TYPE_KPROBE:
	case BPF_PROG_TYPE_TRACEPOINT:
	case BPF_PROG_TYPE_PERF_EVENT:
	case BPF_PROG_TYPE_RAW_TRACEPOINT:
	case BPF_PROG_TYPE_RAW_TRACEPOINT_WRITABLE:
	case BPF_PROG_TYPE_TRACING:
	case BPF_PROG_TYPE_LSM:
	case BPF_PROG_TYPE_STRUCT_OPS: /* has access to struct sock */
	case BPF_PROG_TYPE_EXT: /* extends any prog */
		return true;
	default:
		return false;
	}
}

Project: linux
File: syscall.c

void bpf_link_init(struct bpf_link *link, enum bpf_link_type type,
		   const struct bpf_link_ops *ops, struct bpf_prog *prog)
{
	atomic64_set(&link->refcnt, 1);
	link->type = type;
	link->id = 0;
	link->ops = ops;
	link->prog = prog;
}

Project: linux
File: syscall.c

static int bpf_prog_load(union bpf_attr *attr, union bpf_attr __user *uattr)
{
	enum bpf_prog_type type = attr->prog_type;
	struct bpf_prog *prog, *dst_prog = NULL;
	struct btf *attach_btf = NULL;
	int err;
	char license[128];
	bool is_gpl;

	if (CHECK_ATTR(BPF_PROG_LOAD))
		return -EINVAL;

	if (attr->prog_flags & ~(BPF_F_STRICT_ALIGNMENT |
				 BPF_F_ANY_ALIGNMENT |
				 BPF_F_TEST_STATE_FREQ |
				 BPF_F_SLEEPABLE |
				 BPF_F_TEST_RND_HI32))
		return -EINVAL;

	if (!IS_ENABLED(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) &&
	    (attr->prog_flags & BPF_F_ANY_ALIGNMENT) &&
	    !bpf_capable())
		return -EPERM;

	/* copy eBPF program license from user space */
	if (strncpy_from_user(license, u64_to_user_ptr(attr->license),
			      sizeof(license) - 1) < 0)
		return -EFAULT;
	license[sizeof(license) - 1] = 0;

	/* eBPF programs must be GPL compatible to use GPL-ed functions */
	is_gpl = license_is_gpl_compatible(license);

	if (attr->insn_cnt == 0 ||
	    attr->insn_cnt > (bpf_capable() ? BPF_COMPLEXITY_LIMIT_INSNS : BPF_MAXINSNS))
		return -E2BIG;
	if (type != BPF_PROG_TYPE_SOCKET_FILTER &&
	    type != BPF_PROG_TYPE_CGROUP_SKB &&
	    !bpf_capable())
		return -EPERM;

	if (is_net_admin_prog_type(type) && !capable(CAP_NET_ADMIN) && !capable(CAP_SYS_ADMIN))
		return -EPERM;
	if (is_perfmon_prog_type(type) && !perfmon_capable())
		return -EPERM;

	/* attach_prog_fd/attach_btf_obj_fd can specify fd of either bpf_prog
	 * or btf, we need to check which one it is
	 */
	if (attr->attach_prog_fd) {
		dst_prog = bpf_prog_get(attr->attach_prog_fd);
		if (IS_ERR(dst_prog)) {
			dst_prog = NULL;
			attach_btf = btf_get_by_fd(attr->attach_btf_obj_fd);
			if (IS_ERR(attach_btf))
				return -EINVAL;
			if (!btf_is_kernel(attach_btf)) {
				/* attaching through specifying bpf_prog's BTF
				 * objects directly might be supported eventually
				 */
				btf_put(attach_btf);
				return -ENOTSUPP;
			}
		}
	} else if (attr->attach_btf_id) {
		/* fall back to vmlinux BTF, if BTF type ID is specified */
		attach_btf = bpf_get_btf_vmlinux();
		if (IS_ERR(attach_btf))
			return PTR_ERR(attach_btf);
		if (!attach_btf)
			return -EINVAL;
		btf_get(attach_btf);
	}

	bpf_prog_load_fixup_attach_type(attr);
	if (bpf_prog_load_check_attach(type, attr->expected_attach_type,
				       attach_btf, attr->attach_btf_id,
				       dst_prog)) {
		if (dst_prog)
			bpf_prog_put(dst_prog);
		if (attach_btf)
			btf_put(attach_btf);
		return -EINVAL;
	}

	/* plain bpf_prog allocation */
	prog = bpf_prog_alloc(bpf_prog_size(attr->insn_cnt), GFP_USER);
	if (!prog) {
		if (dst_prog)
			bpf_prog_put(dst_prog);
		if (attach_btf)
			btf_put(attach_btf);
		return -ENOMEM;
	}

	prog->expected_attach_type = attr->expected_attach_type;
	prog->aux->attach_btf = attach_btf;
	prog->aux->attach_btf_id = attr->attach_btf_id;
	prog->aux->dst_prog = dst_prog;
	prog->aux->offload_requested = !!attr->prog_ifindex;
	prog->aux->sleepable = attr->prog_flags & BPF_F_SLEEPABLE;

	err = security_bpf_prog_alloc(prog->aux);
	if (err)
		goto free_prog;

	prog->aux->user = get_current_user();
	prog->len = attr->insn_cnt;

	err = -EFAULT;
	if (copy_from_user(prog->insns, u64_to_user_ptr(attr->insns),
			   bpf_prog_insn_size(prog)) != 0)
		goto free_prog_sec;

	prog->orig_prog = NULL;
	prog->jited = 0;

	atomic64_set(&prog->aux->refcnt, 1);
	prog->gpl_compatible = is_gpl ? 1 : 0;

	if (bpf_prog_is_dev_bound(prog->aux)) {
		err = bpf_prog_offload_init(prog, attr);
		if (err)
			goto free_prog_sec;
	}

	/* find program type: socket_filter vs tracing_filter */
	err = find_prog_type(type, prog);
	if (err < 0)
		goto free_prog_sec;

	prog->aux->load_time = ktime_get_boottime_ns();
	err = bpf_obj_name_cpy(prog->aux->name, attr->prog_name,
			       sizeof(attr->prog_name));
	if (err < 0)
		goto free_prog_sec;

	/* run eBPF verifier */
	err = bpf_check(&prog, attr, uattr);
	if (err < 0)
		goto free_used_maps;

	prog = bpf_prog_select_runtime(prog, &err);
	if (err < 0)
		goto free_used_maps;

	err = bpf_prog_alloc_id(prog);
	if (err)
		goto free_used_maps;

	/* Upon success of bpf_prog_alloc_id(), the BPF prog is
	 * effectively publicly exposed. However, retrieving via
	 * bpf_prog_get_fd_by_id() will take another reference,
	 * therefore it cannot be gone underneath us.
	 *
	 * Only for the time /after/ successful bpf_prog_new_fd()
	 * and before returning to userspace, we might just hold
	 * one reference and any parallel close on that fd could
	 * rip everything out. Hence, below notifications must
	 * happen before bpf_prog_new_fd().
	 *
	 * Also, any failure handling from this point onwards must
	 * be using bpf_prog_put() given the program is exposed.
	 */
	bpf_prog_kallsyms_add(prog);
	perf_event_bpf_event(prog, PERF_BPF_EVENT_PROG_LOAD, 0);
	bpf_audit_prog(prog, BPF_AUDIT_LOAD);

	err = bpf_prog_new_fd(prog);
	if (err < 0)
		bpf_prog_put(prog);
	return err;

free_used_maps:
	/* In case we have subprogs, we need to wait for a grace
	 * period before we can tear down JIT memory since symbols
	 * are already exposed under kallsyms.
	 */
	__bpf_prog_put_noref(prog, prog->aux->func_cnt);
	return err;
free_prog_sec:
	free_uid(prog->aux->user);
	security_bpf_prog_free(prog->aux);
free_prog:
	if (prog->aux->attach_btf)
		btf_put(prog->aux->attach_btf);
	bpf_prog_free(prog);
	return err;
}

Project: linux
File: syscall.c

static void bpf_map_free_deferred(struct work_struct *work)
{
	struct bpf_map *map = container_of(work, struct bpf_map, work);

	security_bpf_map_free(map);
	bpf_map_release_memcg(map);
	/* implementation dependent freeing */
	map->ops->map_free(map);
}

Project: linux
File: syscall.c

static void bpf_link_put_deferred(struct work_struct *work)
{
	struct bpf_link *link = container_of(work, struct bpf_link, work);

	bpf_link_free(link);
}

Project: linux
File: syscall.c

struct bpf_prog *bpf_prog_get_type_dev(u32 ufd, enum bpf_prog_type type,
				       bool attach_drv)
{
	return __bpf_prog_get(ufd, &type, attach_drv);
}

Project: linux
File: verifier.c

static int check_helper_mem_access(struct bpf_verifier_env *env, int regno,
				   int access_size, bool zero_size_allowed,
				   struct bpf_call_arg_meta *meta)
{
	struct bpf_reg_state *regs = cur_regs(env), *reg = &regs[regno];

	switch (reg->type) {
	case PTR_TO_PACKET:
	case PTR_TO_PACKET_META:
		return check_packet_access(env, regno, reg->off, access_size,
					   zero_size_allowed);
	case PTR_TO_MAP_VALUE:
		if (check_map_access_type(env, regno, reg->off, access_size,
					  meta && meta->raw_mode ? BPF_WRITE :
					  BPF_READ))
			return -EACCES;
		return check_map_access(env, regno, reg->off, access_size,
					zero_size_allowed);
	case PTR_TO_MEM:
		return check_mem_region_access(env, regno, reg->off,
					       access_size, reg->mem_size,
					       zero_size_allowed);
	case PTR_TO_RDONLY_BUF:
		if (meta && meta->raw_mode)
			return -EACCES;
		return check_buffer_access(env, reg, regno, reg->off,
					   access_size, zero_size_allowed,
					   "rdonly",
					   &env->prog->aux->max_rdonly_access);
	case PTR_TO_RDWR_BUF:
		return check_buffer_access(env, reg, regno, reg->off,
					   access_size, zero_size_allowed,
					   "rdwr",
					   &env->prog->aux->max_rdwr_access);
	case PTR_TO_STACK:
		return check_stack_range_initialized(
				env,
				regno, reg->off, access_size,
				zero_size_allowed, ACCESS_HELPER, meta);
	default: /* scalar_value or invalid ptr */
		/* Allow zero-byte read from NULL, regardless of pointer type */
		if (zero_size_allowed && access_size == 0 &&
		    register_is_null(reg))
			return 0;

		verbose(env, "R%d type=%s expected=%s\n", regno,
			reg_type_str[reg->type],
			reg_type_str[PTR_TO_STACK]);
		return -EACCES;
	}
}

Project: linux
File: syscall.c

static int bpf_link_get_info_by_fd(struct file *file,
				  struct bpf_link *link,
				  const union bpf_attr *attr,
				  union bpf_attr __user *uattr)
{
	struct bpf_link_info __user *uinfo = u64_to_user_ptr(attr->info.info);
	struct bpf_link_info info;
	u32 info_len = attr->info.info_len;
	int err;

	err = bpf_check_uarg_tail_zero(uinfo, sizeof(info), info_len);
	if (err)
		return err;
	info_len = min_t(u32, sizeof(info), info_len);

	memset(&info, 0, sizeof(info));
	if (copy_from_user(&info, uinfo, info_len))
		return -EFAULT;

	info.type = link->type;
	info.id = link->id;
	info.prog_id = link->prog->aux->id;

	if (link->ops->fill_link_info) {
		err = link->ops->fill_link_info(link, &info);
		if (err)
			return err;
	}

	if (copy_to_user(uinfo, &info, info_len) ||
	    put_user(info_len, &uattr->info.info_len))
		return -EFAULT;

	return 0;
}

Project: linux
File: verifier.c

static int resolve_pseudo_ldimm64(struct bpf_verifier_env *env)
{
	struct bpf_insn *insn = env->prog->insnsi;
	int insn_cnt = env->prog->len;
	int i, j, err;

	err = bpf_prog_calc_tag(env->prog);
	if (err)
		return err;

	for (i = 0; i < insn_cnt; i++, insn++) {
		if (BPF_CLASS(insn->code) == BPF_LDX &&
		    (BPF_MODE(insn->code) != BPF_MEM || insn->imm != 0)) {
			verbose(env, "BPF_LDX uses reserved fields\n");
			return -EINVAL;
		}

		if (insn[0].code == (BPF_LD | BPF_IMM | BPF_DW)) {
			struct bpf_insn_aux_data *aux;
			struct bpf_map *map;
			struct fd f;
			u64 addr;

			if (i == insn_cnt - 1 || insn[1].code != 0 ||
			    insn[1].dst_reg != 0 || insn[1].src_reg != 0 ||
			    insn[1].off != 0) {
				verbose(env, "invalid bpf_ld_imm64 insn\n");
				return -EINVAL;
			}

			if (insn[0].src_reg == 0)
				/* valid generic load 64-bit imm */
				goto next_insn;

			if (insn[0].src_reg == BPF_PSEUDO_BTF_ID) {
				aux = &env->insn_aux_data[i];
				err = check_pseudo_btf_id(env, insn, aux);
				if (err)
					return err;
				goto next_insn;
			}

			/* In final convert_pseudo_ld_imm64() step, this is
			 * converted into regular 64-bit imm load insn.
			 */
			if ((insn[0].src_reg != BPF_PSEUDO_MAP_FD &&
			     insn[0].src_reg != BPF_PSEUDO_MAP_VALUE) ||
			    (insn[0].src_reg == BPF_PSEUDO_MAP_FD &&
			     insn[1].imm != 0)) {
				verbose(env,
					"unrecognized bpf_ld_imm64 insn\n");
				return -EINVAL;
			}

			f = fdget(insn[0].imm);
			map = __bpf_map_get(f);
			if (IS_ERR(map)) {
				verbose(env, "fd %d is not pointing to valid bpf_map\n",
					insn[0].imm);
				return PTR_ERR(map);
			}

			err = check_map_prog_compatibility(env, map, env->prog);
			if (err) {
				fdput(f);
				return err;
			}

			aux = &env->insn_aux_data[i];
			if (insn->src_reg == BPF_PSEUDO_MAP_FD) {
				addr = (unsigned long)map;
			} else {
				u32 off = insn[1].imm;

				if (off >= BPF_MAX_VAR_OFF) {
					verbose(env, "direct value offset of %u is not allowed\n", off);
					fdput(f);
					return -EINVAL;
				}

				if (!map->ops->map_direct_value_addr) {
					verbose(env, "no direct value access support for this map type\n");
					fdput(f);
					return -EINVAL;
				}

				err = map->ops->map_direct_value_addr(map, &addr, off);
				if (err) {
					verbose(env, "invalid access to map value pointer, value_size=%u off=%u\n",
						map->value_size, off);
					fdput(f);
					return err;
				}

				aux->map_off = off;
				addr += off;
			}

			insn[0].imm = (u32)addr;
			insn[1].imm = addr >> 32;

			/* check whether we recorded this map already */
			for (j = 0; j < env->used_map_cnt; j++) {
				if (env->used_maps[j] == map) {
					aux->map_index = j;
					fdput(f);
					goto next_insn;
				}
			}

			if (env->used_map_cnt >= MAX_USED_MAPS) {
				fdput(f);
				return -E2BIG;
			}

			/* hold the map. If the program is rejected by verifier,
			 * the map will be released by release_maps() or it
			 * will be used by the valid program until it's unloaded
			 * and all maps are released in free_used_maps()
			 */
			bpf_map_inc(map);

			aux->map_index = env->used_map_cnt;
			env->used_maps[env->used_map_cnt++] = map;

			if (bpf_map_is_cgroup_storage(map) &&
			    bpf_cgroup_storage_assign(env->prog->aux, map)) {
				verbose(env, "only one cgroup storage of each type is allowed\n");
				fdput(f);
				return -EBUSY;
			}

			fdput(f);
next_insn:
			insn++;
			i++;
			continue;
		}

		/* Basic sanity check before we invest more work here. */
		if (!bpf_opcode_in_insntable(insn->code)) {
			verbose(env, "unknown opcode %02x\n", insn->code);
			return -EINVAL;
		}
	}

	/* now all pseudo BPF_LD_IMM64 instructions load valid
	 * 'struct bpf_map *' into a register instead of user map_fd.
	 * These pointers will be used later by verifier to validate map access.
	 */
	return 0;
}

Project: linux
File: syscall.c

struct bpf_prog *bpf_prog_inc_not_zero(struct bpf_prog *prog)
{
	int refold;

	refold = atomic64_fetch_add_unless(&prog->aux->refcnt, 1, 0);

	if (!refold)
		return ERR_PTR(-ENOENT);

	return prog;
}

Project: linux
File: syscall.c

int bpf_link_settle(struct bpf_link_primer *primer)
{
	/* make bpf_link fetchable by ID */
	spin_lock_bh(&link_idr_lock);
	primer->link->id = primer->id;
	spin_unlock_bh(&link_idr_lock);
	/* make bpf_link fetchable by FD */
	fd_install(primer->fd, primer->file);
	/* pass through installed FD */
	return primer->fd;
}

Project: linux
File: syscall.c

struct bpf_link *bpf_link_get_from_fd(u32 ufd)
{
	struct fd f = fdget(ufd);
	struct bpf_link *link;

	if (!f.file)
		return ERR_PTR(-EBADF);
	if (f.file->f_op != &bpf_link_fops) {
		fdput(f);
		return ERR_PTR(-EINVAL);
	}

	link = f.file->private_data;
	bpf_link_inc(link);
	fdput(f);

	return link;
}

Project: linux
File: syscall.c

struct bpf_map *bpf_map_get(u32 ufd)
{
	struct fd f = fdget(ufd);
	struct bpf_map *map;

	map = __bpf_map_get(f);
	if (IS_ERR(map))
		return map;

	bpf_map_inc(map);
	fdput(f);

	return map;
}

Project: linux
File: verifier.c

static int check_func_call(struct bpf_verifier_env *env, struct bpf_insn *insn,
			   int *insn_idx)
{
	struct bpf_verifier_state *state = env->cur_state;
	struct bpf_func_info_aux *func_info_aux;
	struct bpf_func_state *caller, *callee;
	int i, err, subprog, target_insn;
	bool is_global = false;

	if (state->curframe + 1 >= MAX_CALL_FRAMES) {
		verbose(env, "the call stack of %d frames is too deep\n",
			state->curframe + 2);
		return -E2BIG;
	}

	target_insn = *insn_idx + insn->imm;
	subprog = find_subprog(env, target_insn + 1);
	if (subprog < 0) {
		verbose(env, "verifier bug. No program starts at insn %d\n",
			target_insn + 1);
		return -EFAULT;
	}

	caller = state->frame[state->curframe];
	if (state->frame[state->curframe + 1]) {
		verbose(env, "verifier bug. Frame %d already allocated\n",
			state->curframe + 1);
		return -EFAULT;
	}

	func_info_aux = env->prog->aux->func_info_aux;
	if (func_info_aux)
		is_global = func_info_aux[subprog].linkage == BTF_FUNC_GLOBAL;
	err = btf_check_func_arg_match(env, subprog, caller->regs);
	if (err == -EFAULT)
		return err;
	if (is_global) {
		if (err) {
			verbose(env, "Caller passes invalid args into func#%d\n",
				subprog);
			return err;
		} else {
			if (env->log.level & BPF_LOG_LEVEL)
				verbose(env,
					"Func#%d is global and valid. Skipping.\n",
					subprog);
			clear_caller_saved_regs(env, caller->regs);

			/* All global functions return a 64-bit SCALAR_VALUE */
			mark_reg_unknown(env, caller->regs, BPF_REG_0);
			caller->regs[BPF_REG_0].subreg_def = DEF_NOT_SUBREG;

			/* continue with next insn after call */
			return 0;
		}
	}

	callee = kzalloc(sizeof(*callee), GFP_KERNEL);
	if (!callee)
		return -ENOMEM;
	state->frame[state->curframe + 1] = callee;

	/* callee cannot access r0, r6 - r9 for reading and has to write
	 * into its own stack before reading from it.
	 * callee can read/write into caller's stack
	 */
	init_func_state(env, callee,
			/* remember the callsite, it will be used by bpf_exit */
			*insn_idx /* callsite */,
			state->curframe + 1 /* frameno within this callchain */,
			subprog /* subprog number within this prog */);

	/* Transfer references to the callee */
	err = transfer_reference_state(callee, caller);
	if (err)
		return err;

	/* copy r1 - r5 args that callee can access.  The copy includes parent
	 * pointers, which connects us up to the liveness chain
	 */
	for (i = BPF_REG_1; i <= BPF_REG_5; i++)
		callee->regs[i] = caller->regs[i];

	clear_caller_saved_regs(env, caller->regs);

	/* only increment it after check_reg_arg() finished */
	state->curframe++;

	/* and go analyze first insn of the callee */
	*insn_idx = target_insn;

	if (env->log.level & BPF_LOG_LEVEL) {
		verbose(env, "caller:\n");
		print_verifier_state(env, caller);
		verbose(env, "callee:\n");
		print_verifier_state(env, callee);
	}
	return 0;
}

Project: linux
File: syscall.c

static struct bpf_prog *____bpf_prog_get(struct fd f)
{
	if (!f.file)
		return ERR_PTR(-EBADF);
	if (f.file->f_op != &bpf_prog_fops) {
		fdput(f);
		return ERR_PTR(-EINVAL);
	}

	return f.file->private_data;
}

Project: linux
File: syscall.c

static int bpf_raw_tp_link_fill_link_info(const struct bpf_link *link,
					  struct bpf_link_info *info)
{
	struct bpf_raw_tp_link *raw_tp_link =
		container_of(link, struct bpf_raw_tp_link, link);
	char __user *ubuf = u64_to_user_ptr(info->raw_tracepoint.tp_name);
	const char *tp_name = raw_tp_link->btp->tp->name;
	u32 ulen = info->raw_tracepoint.tp_name_len;
	size_t tp_len = strlen(tp_name);

	if (!ulen ^ !ubuf)
		return -EINVAL;

	info->raw_tracepoint.tp_name_len = tp_len + 1;

	if (!ubuf)
		return 0;

	if (ulen >= tp_len + 1) {
		if (copy_to_user(ubuf, tp_name, tp_len + 1))
			return -EFAULT;
	} else {
		char zero = '\0';

		if (copy_to_user(ubuf, tp_name, ulen - 1))
			return -EFAULT;
		if (put_user(zero, ubuf + ulen - 1))
			return -EFAULT;
		return -ENOSPC;
	}

	return 0;
}

Project: linux
File: syscall.c

void bpf_link_cleanup(struct bpf_link_primer *primer)
{
	primer->link->prog = NULL;
	bpf_link_free_id(primer->id);
	fput(primer->file);
	put_unused_fd(primer->fd);
}

Project: linux
File: syscall.c

static int find_prog_type(enum bpf_prog_type type, struct bpf_prog *prog)
{
	const struct bpf_prog_ops *ops;

	if (type >= ARRAY_SIZE(bpf_prog_types))
		return -EINVAL;
	type = array_index_nospec(type, ARRAY_SIZE(bpf_prog_types));
	ops = bpf_prog_types[type];
	if (!ops)
		return -EINVAL;

	if (!bpf_prog_is_dev_bound(prog->aux))
		prog->aux->ops = ops;
	else
		prog->aux->ops = &bpf_offload_prog_ops;
	prog->type = type;
	return 0;
}

Project: linux
File: verifier.c

static void print_verifier_state(struct bpf_verifier_env *env,
				 const struct bpf_func_state *state)
{
	const struct bpf_reg_state *reg;
	enum bpf_reg_type t;
	int i;

	if (state->frameno)
		verbose(env, " frame%d:", state->frameno);
	for (i = 0; i < MAX_BPF_REG; i++) {
		reg = &state->regs[i];
		t = reg->type;
		if (t == NOT_INIT)
			continue;
		verbose(env, " R%d", i);
		print_liveness(env, reg->live);
		verbose(env, "=%s", reg_type_str[t]);
		if (t == SCALAR_VALUE && reg->precise)
			verbose(env, "P");
		if ((t == SCALAR_VALUE || t == PTR_TO_STACK) &&
		    tnum_is_const(reg->var_off)) {
			/* reg->off should be 0 for SCALAR_VALUE */
			verbose(env, "%lld", reg->var_off.value + reg->off);
		} else {
			if (t == PTR_TO_BTF_ID ||
			    t == PTR_TO_BTF_ID_OR_NULL ||
			    t == PTR_TO_PERCPU_BTF_ID)
				verbose(env, "%s", kernel_type_name(reg->btf, reg->btf_id));
			verbose(env, "(id=%d", reg->id);
			if (reg_type_may_be_refcounted_or_null(t))
				verbose(env, ",ref_obj_id=%d", reg->ref_obj_id);
			if (t != SCALAR_VALUE)
				verbose(env, ",off=%d", reg->off);
			if (type_is_pkt_pointer(t))
				verbose(env, ",r=%d", reg->range);
			else if (t == CONST_PTR_TO_MAP ||
				 t == PTR_TO_MAP_VALUE ||
				 t == PTR_TO_MAP_VALUE_OR_NULL)
				verbose(env, ",ks=%d,vs=%d",
					reg->map_ptr->key_size,
					reg->map_ptr->value_size);
			if (tnum_is_const(reg->var_off)) {
				/* Typically an immediate SCALAR_VALUE, but
				 * could be a pointer whose offset is too big
				 * for reg->off
				 */
				verbose(env, ",imm=%llx", reg->var_off.value);
			} else {
				if (reg->smin_value != reg->umin_value &&
				    reg->smin_value != S64_MIN)
					verbose(env, ",smin_value=%lld",
						(long long)reg->smin_value);
				if (reg->smax_value != reg->umax_value &&
				    reg->smax_value != S64_MAX)
					verbose(env, ",smax_value=%lld",
						(long long)reg->smax_value);
				if (reg->umin_value != 0)
					verbose(env, ",umin_value=%llu",
						(unsigned long long)reg->umin_value);
				if (reg->umax_value != U64_MAX)
					verbose(env, ",umax_value=%llu",
						(unsigned long long)reg->umax_value);
				if (!tnum_is_unknown(reg->var_off)) {
					char tn_buf[48];

					tnum_strn(tn_buf, sizeof(tn_buf), reg->var_off);
					verbose(env, ",var_off=%s", tn_buf);
				}
				if (reg->s32_min_value != reg->smin_value &&
				    reg->s32_min_value != S32_MIN)
					verbose(env, ",s32_min_value=%d",
						(int)(reg->s32_min_value));
				if (reg->s32_max_value != reg->smax_value &&
				    reg->s32_max_value != S32_MAX)
					verbose(env, ",s32_max_value=%d",
						(int)(reg->s32_max_value));
				if (reg->u32_min_value != reg->umin_value &&
				    reg->u32_min_value != U32_MIN)
					verbose(env, ",u32_min_value=%d",
						(int)(reg->u32_min_value));
				if (reg->u32_max_value != reg->umax_value &&
				    reg->u32_max_value != U32_MAX)
					verbose(env, ",u32_max_value=%d",
						(int)(reg->u32_max_value));
			}
			verbose(env, ")");
		}
	}
	for (i = 0; i < state->allocated_stack / BPF_REG_SIZE; i++) {
		char types_buf[BPF_REG_SIZE + 1];
		bool valid = false;
		int j;

		for (j = 0; j < BPF_REG_SIZE; j++) {
			if (state->stack[i].slot_type[j] != STACK_INVALID)
				valid = true;
			types_buf[j] = slot_type_char[
					state->stack[i].slot_type[j]];
		}
		types_buf[BPF_REG_SIZE] = 0;
		if (!valid)
			continue;
		verbose(env, " fp%d", (-i - 1) * BPF_REG_SIZE);
		print_liveness(env, state->stack[i].spilled_ptr.live);
		if (state->stack[i].slot_type[0] == STACK_SPILL) {
			reg = &state->stack[i].spilled_ptr;
			t = reg->type;
			verbose(env, "=%s", reg_type_str[t]);
			if (t == SCALAR_VALUE && reg->precise)
				verbose(env, "P");
			if (t == SCALAR_VALUE && tnum_is_const(reg->var_off))
				verbose(env, "%lld", reg->var_off.value + reg->off);
		} else {
			verbose(env, "=%s", types_buf);
		}
	}
	if (state->acquired_refs && state->refs[0].id) {
		verbose(env, " refs=%d", state->refs[0].id);
		for (i = 1; i < state->acquired_refs; i++)
			if (state->refs[i].id)
				verbose(env, ",%d", state->refs[i].id);
	}
	verbose(env, "\n");
}

Project: linux
File: syscall.c

static void bpf_map_save_memcg(struct bpf_map *map)
{
	map->memcg = get_mem_cgroup_from_mm(current->mm);
}

Project: linux
File: syscall.c

void bpf_map_init_from_attr(struct bpf_map *map, union bpf_attr *attr)
{
	map->map_type = attr->map_type;
	map->key_size = attr->key_size;
	map->value_size = attr->value_size;
	map->max_entries = attr->max_entries;
	map->map_flags = bpf_map_flags_retain_permanent(attr->map_flags);
	map->numa_node = bpf_map_attr_numa_node(attr);
}

Project: linux
File: syscall.c

static int bpf_link_get_fd_by_id(const union bpf_attr *attr)
{
	struct bpf_link *link;
	u32 id = attr->link_id;
	int fd;

	if (CHECK_ATTR(BPF_LINK_GET_FD_BY_ID))
		return -EINVAL;

	if (!capable(CAP_SYS_ADMIN))
		return -EPERM;

	link = bpf_link_by_id(id);
	if (IS_ERR(link))
		return PTR_ERR(link);

	fd = bpf_link_new_fd(link);
	if (fd < 0)
		bpf_link_put(link);

	return fd;
}

Project: linux
File: verifier.c

static int check_ld_imm(struct bpf_verifier_env *env, struct bpf_insn *insn)
{
	struct bpf_insn_aux_data *aux = cur_aux(env);
	struct bpf_reg_state *regs = cur_regs(env);
	struct bpf_reg_state *dst_reg;
	struct bpf_map *map;
	int err;

	if (BPF_SIZE(insn->code) != BPF_DW) {
		verbose(env, "invalid BPF_LD_IMM insn\n");
		return -EINVAL;
	}
	if (insn->off != 0) {
		verbose(env, "BPF_LD_IMM64 uses reserved fields\n");
		return -EINVAL;
	}

	err = check_reg_arg(env, insn->dst_reg, DST_OP);
	if (err)
		return err;

	dst_reg = &regs[insn->dst_reg];
	if (insn->src_reg == 0) {
		u64 imm = ((u64)(insn + 1)->imm << 32) | (u32)insn->imm;

		dst_reg->type = SCALAR_VALUE;
		__mark_reg_known(&regs[insn->dst_reg], imm);
		return 0;
	}

	if (insn->src_reg == BPF_PSEUDO_BTF_ID) {
		mark_reg_known_zero(env, regs, insn->dst_reg);

		dst_reg->type = aux->btf_var.reg_type;
		switch (dst_reg->type) {
		case PTR_TO_MEM:
			dst_reg->mem_size = aux->btf_var.mem_size;
			break;
		case PTR_TO_BTF_ID:
		case PTR_TO_PERCPU_BTF_ID:
			dst_reg->btf = aux->btf_var.btf;
			dst_reg->btf_id = aux->btf_var.btf_id;
			break;
		default:
			verbose(env, "bpf verifier is misconfigured\n");
			return -EFAULT;
		}
		return 0;
	}

	map = env->used_maps[aux->map_index];
	mark_reg_known_zero(env, regs, insn->dst_reg);
	dst_reg->map_ptr = map;

	if (insn->src_reg == BPF_PSEUDO_MAP_VALUE) {
		dst_reg->type = PTR_TO_MAP_VALUE;
		dst_reg->off = aux->map_off;
		if (map_value_has_spin_lock(map))
			dst_reg->id = ++env->id_gen;
	} else if (insn->src_reg == BPF_PSEUDO_MAP_FD) {
		dst_reg->type = CONST_PTR_TO_MAP;
	} else {
		verbose(env, "bpf verifier is misconfigured\n");
		return -EINVAL;
	}

	return 0;
}

Project: linux
File: verifier.c

int bpf_check(struct bpf_prog **prog, union bpf_attr *attr,
	      union bpf_attr __user *uattr)
{
	u64 start_time = ktime_get_ns();
	struct bpf_verifier_env *env;
	struct bpf_verifier_log *log;
	int i, len, ret = -EINVAL;
	bool is_priv;

	/* no program is valid */
	if (ARRAY_SIZE(bpf_verifier_ops) == 0)
		return -EINVAL;

	/* 'struct bpf_verifier_env' can be global, but since it's not small,
	 * allocate/free it every time bpf_check() is called
	 */
	env = kzalloc(sizeof(struct bpf_verifier_env), GFP_KERNEL);
	if (!env)
		return -ENOMEM;
	log = &env->log;

	len = (*prog)->len;
	env->insn_aux_data =
		vzalloc(array_size(sizeof(struct bpf_insn_aux_data), len));
	ret = -ENOMEM;
	if (!env->insn_aux_data)
		goto err_free_env;
	for (i = 0; i < len; i++)
		env->insn_aux_data[i].orig_idx = i;
	env->prog = *prog;
	env->ops = bpf_verifier_ops[env->prog->type];
	is_priv = bpf_capable();

	bpf_get_btf_vmlinux();

	/* grab the mutex to protect few globals used by verifier */
	if (!is_priv)
		mutex_lock(&bpf_verifier_lock);

	if (attr->log_level || attr->log_buf || attr->log_size) {
		/* user requested verbose verifier output
		 * and supplied buffer to store the verification trace
		 */
		log->level = attr->log_level;
		log->ubuf = (char __user *) (unsigned long) attr->log_buf;
		log->len_total = attr->log_size;

		ret = -EINVAL;
		/* log attributes have to be sane */
		if (log->len_total < 128 || log->len_total > UINT_MAX >> 2 ||
		    !log->level || !log->ubuf || log->level & ~BPF_LOG_MASK)
			goto err_unlock;
	}

	if (IS_ERR(btf_vmlinux)) {
		/* Either gcc or pahole or kernel are broken. */
		verbose(env, "in-kernel BTF is malformed\n");
		ret = PTR_ERR(btf_vmlinux);
		goto skip_full_check;
	}

	env->strict_alignment = !!(attr->prog_flags & BPF_F_STRICT_ALIGNMENT);
	if (!IS_ENABLED(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS))
		env->strict_alignment = true;
	if (attr->prog_flags & BPF_F_ANY_ALIGNMENT)
		env->strict_alignment = false;

	env->allow_ptr_leaks = bpf_allow_ptr_leaks();
	env->allow_uninit_stack = bpf_allow_uninit_stack();
	env->allow_ptr_to_map_access = bpf_allow_ptr_to_map_access();
	env->bypass_spec_v1 = bpf_bypass_spec_v1();
	env->bypass_spec_v4 = bpf_bypass_spec_v4();
	env->bpf_capable = bpf_capable();

	if (is_priv)
		env->test_state_freq = attr->prog_flags & BPF_F_TEST_STATE_FREQ;

	if (bpf_prog_is_dev_bound(env->prog->aux)) {
		ret = bpf_prog_offload_verifier_prep(env->prog);
		if (ret)
			goto skip_full_check;
	}

	env->explored_states = kvcalloc(state_htab_size(env),
				       sizeof(struct bpf_verifier_state_list *),
				       GFP_USER);
	ret = -ENOMEM;
	if (!env->explored_states)
		goto skip_full_check;

	ret = check_subprogs(env);
	if (ret < 0)
		goto skip_full_check;

	ret = check_btf_info(env, attr, uattr);
	if (ret < 0)
		goto skip_full_check;

	ret = check_attach_btf_id(env);
	if (ret)
		goto skip_full_check;

	ret = resolve_pseudo_ldimm64(env);
	if (ret < 0)
		goto skip_full_check;

	ret = check_cfg(env);
	if (ret < 0)
		goto skip_full_check;

	ret = do_check_subprogs(env);
	ret = ret ?: do_check_main(env);

	if (ret == 0 && bpf_prog_is_dev_bound(env->prog->aux))
		ret = bpf_prog_offload_finalize(env);

skip_full_check:
	kvfree(env->explored_states);

	if (ret == 0)
		ret = check_max_stack_depth(env);

	/* instruction rewrites happen after this point */
	if (is_priv) {
		if (ret == 0)
			opt_hard_wire_dead_code_branches(env);
		if (ret == 0)
			ret = opt_remove_dead_code(env);
		if (ret == 0)
			ret = opt_remove_nops(env);
	} else {
		if (ret == 0)
			sanitize_dead_code(env);
	}

	if (ret == 0)
		/* program is valid, convert *(u32*)(ctx + off) accesses */
		ret = convert_ctx_accesses(env);

	if (ret == 0)
		ret = fixup_bpf_calls(env);

	/* do 32-bit optimization after insn patching has done so those patched
	 * insns could be handled correctly.
	 */
	if (ret == 0 && !bpf_prog_is_dev_bound(env->prog->aux)) {
		ret = opt_subreg_zext_lo32_rnd_hi32(env, attr);
		env->prog->aux->verifier_zext = bpf_jit_needs_zext() ? !ret
								     : false;
	}

	if (ret == 0)
		ret = fixup_call_args(env);

	env->verification_time = ktime_get_ns() - start_time;
	print_verification_stats(env);

	if (log->level && bpf_verifier_log_full(log))
		ret = -ENOSPC;
	if (log->level && !log->ubuf) {
		ret = -EFAULT;
		goto err_release_maps;
	}

	if (ret)
		goto err_release_maps;

	if (env->used_map_cnt) {
		/* if program passed verifier, update used_maps in bpf_prog_info */
		env->prog->aux->used_maps = kmalloc_array(env->used_map_cnt,
							  sizeof(env->used_maps[0]),
							  GFP_KERNEL);

		if (!env->prog->aux->used_maps) {
			ret = -ENOMEM;
			goto err_release_maps;
		}

		memcpy(env->prog->aux->used_maps, env->used_maps,
		       sizeof(env->used_maps[0]) * env->used_map_cnt);
		env->prog->aux->used_map_cnt = env->used_map_cnt;
	}
	if (env->used_btf_cnt) {
		/* if program passed verifier, update used_btfs in bpf_prog_aux */
		env->prog->aux->used_btfs = kmalloc_array(env->used_btf_cnt,
							  sizeof(env->used_btfs[0]),
							  GFP_KERNEL);
		if (!env->prog->aux->used_btfs) {
			ret = -ENOMEM;
			goto err_release_maps;
		}

		memcpy(env->prog->aux->used_btfs, env->used_btfs,
		       sizeof(env->used_btfs[0]) * env->used_btf_cnt);
		env->prog->aux->used_btf_cnt = env->used_btf_cnt;
	}
	if (env->used_map_cnt || env->used_btf_cnt) {
		/* program is valid. Convert pseudo bpf_ld_imm64 into generic
		 * bpf_ld_imm64 instructions
		 */
		convert_pseudo_ld_imm64(env);
	}

	adjust_btf_func(env);

err_release_maps:
	if (!env->prog->aux->used_maps)
		/* if we didn't copy map pointers into bpf_prog_info, release
		 * them now. Otherwise free_used_maps() will release them.
		 */
		release_maps(env);
	if (!env->prog->aux->used_btfs)
		release_btfs(env);

	/* extension progs temporarily inherit the attach_type of their targets
	   for verification purposes, so set it back to zero before returning
	 */
	if (env->prog->type == BPF_PROG_TYPE_EXT)
		env->prog->expected_attach_type = 0;

	*prog = env->prog;
err_unlock:
	if (!is_priv)
		mutex_unlock(&bpf_verifier_lock);
	vfree(env->insn_aux_data);
err_free_env:
	kfree(env);
	return ret;
}

Project: linux
File: syscall.c

void __percpu *bpf_map_alloc_percpu(const struct bpf_map *map, size_t size,
				    size_t align, gfp_t flags)
{
	struct mem_cgroup *old_memcg;
	void __percpu *ptr;

	old_memcg = set_active_memcg(map->memcg);
	ptr = __alloc_percpu_gfp(size, align, flags | __GFP_ACCOUNT);
	set_active_memcg(old_memcg);

	return ptr;
}

Project: linux
File: verifier.c

static int check_ptr_alignment(struct bpf_verifier_env *env,
			       const struct bpf_reg_state *reg, int off,
			       int size, bool strict_alignment_once)
{
	bool strict = env->strict_alignment || strict_alignment_once;
	const char *pointer_desc = "";

	switch (reg->type) {
	case PTR_TO_PACKET:
	case PTR_TO_PACKET_META:
		/* Special case, because of NET_IP_ALIGN. Given metadata sits
		 * right in front, treat it the very same way.
		 */
		return check_pkt_ptr_alignment(env, reg, off, size, strict);
	case PTR_TO_FLOW_KEYS:
		pointer_desc = "flow keys ";
		break;
	case PTR_TO_MAP_VALUE:
		pointer_desc = "value ";
		break;
	case PTR_TO_CTX:
		pointer_desc = "context ";
		break;
	case PTR_TO_STACK:
		pointer_desc = "stack ";
		/* The stack spill tracking logic in check_stack_write_fixed_off()
		 * and check_stack_read_fixed_off() relies on stack accesses being
		 * aligned.
		 */
		strict = true;
		break;
	case PTR_TO_SOCKET:
		pointer_desc = "sock ";
		break;
	case PTR_TO_SOCK_COMMON:
		pointer_desc = "sock_common ";
		break;
	case PTR_TO_TCP_SOCK:
		pointer_desc = "tcp_sock ";
		break;
	case PTR_TO_XDP_SOCK:
		pointer_desc = "xdp_sock ";
		break;
	default:
		break;
	}
	return check_generic_ptr_alignment(env, reg, pointer_desc, off, size,
					   strict);
}

Project: linux
File: syscall.c

int __weak bpf_stackmap_copy(struct bpf_map *map, void *key, void *value)
{
	return -ENOTSUPP;
}

Project: linux
File: syscall.c

static int set_info_rec_size(struct bpf_prog_info *info)
{
	/*
	 * Ensure info.*_rec_size is the same as kernel expected size
	 *
	 * or
	 *
	 * Only allow zero *_rec_size if both _rec_size and _cnt are
	 * zero.  In this case, the kernel will set the expected
	 * _rec_size back to the info.
	 */

	if ((info->nr_func_info || info->func_info_rec_size) &&
	    info->func_info_rec_size != sizeof(struct bpf_func_info))
		return -EINVAL;

	if ((info->nr_line_info || info->line_info_rec_size) &&
	    info->line_info_rec_size != sizeof(struct bpf_line_info))
		return -EINVAL;

	if ((info->nr_jited_line_info || info->jited_line_info_rec_size) &&
	    info->jited_line_info_rec_size != sizeof(__u64))
		return -EINVAL;

	info->func_info_rec_size = sizeof(struct bpf_func_info);
	info->line_info_rec_size = sizeof(struct bpf_line_info);
	info->jited_line_info_rec_size = sizeof(__u64);

	return 0;
}

Project: linux
File: syscall.c

int generic_map_update_batch(struct bpf_map *map,
			     const union bpf_attr *attr,
			     union bpf_attr __user *uattr)
{
	void __user *values = u64_to_user_ptr(attr->batch.values);
	void __user *keys = u64_to_user_ptr(attr->batch.keys);
	u32 value_size, cp, max_count;
	int ufd = attr->map_fd;
	void *key, *value;
	struct fd f;
	int err = 0;

	f = fdget(ufd);
	if (attr->batch.elem_flags & ~BPF_F_LOCK)
		return -EINVAL;

	if ((attr->batch.elem_flags & BPF_F_LOCK) &&
	    !map_value_has_spin_lock(map)) {
		return -EINVAL;
	}

	value_size = bpf_map_value_size(map);

	max_count = attr->batch.count;
	if (!max_count)
		return 0;

	key = kmalloc(map->key_size, GFP_USER | __GFP_NOWARN);
	if (!key)
		return -ENOMEM;

	value = kmalloc(value_size, GFP_USER | __GFP_NOWARN);
	if (!value) {
		kfree(key);
		return -ENOMEM;
	}

	for (cp = 0; cp < max_count; cp++) {
		err = -EFAULT;
		if (copy_from_user(key, keys + cp * map->key_size,
		    map->key_size) ||
		    copy_from_user(value, values + cp * value_size, value_size))
			break;

		err = bpf_map_update_value(map, f, key, value,
					   attr->batch.elem_flags);

		if (err)
			break;
	}

	if (copy_to_user(&uattr->batch.count, &cp, sizeof(cp)))
		err = -EFAULT;

	kfree(value);
	kfree(key);
	return err;
}

Project: linux
File: syscall.c

static struct bpf_insn *bpf_insn_prepare_dump(const struct bpf_prog *prog,
					      const struct cred *f_cred)
{
	const struct bpf_map *map;
	struct bpf_insn *insns;
	u32 off, type;
	u64 imm;
	u8 code;
	int i;

	insns = kmemdup(prog->insnsi, bpf_prog_insn_size(prog),
			GFP_USER);
	if (!insns)
		return insns;

	for (i = 0; i < prog->len; i++) {
		code = insns[i].code;

		if (code == (BPF_JMP | BPF_TAIL_CALL)) {
			insns[i].code = BPF_JMP | BPF_CALL;
			insns[i].imm = BPF_FUNC_tail_call;
			/* fall-through */
		}
		if (code == (BPF_JMP | BPF_CALL) ||
		    code == (BPF_JMP | BPF_CALL_ARGS)) {
			if (code == (BPF_JMP | BPF_CALL_ARGS))
				insns[i].code = BPF_JMP | BPF_CALL;
			if (!bpf_dump_raw_ok(f_cred))
				insns[i].imm = 0;
			continue;
		}
		if (BPF_CLASS(code) == BPF_LDX && BPF_MODE(code) == BPF_PROBE_MEM) {
			insns[i].code = BPF_LDX | BPF_SIZE(code) | BPF_MEM;
			continue;
		}

		if (code != (BPF_LD | BPF_IMM | BPF_DW))
			continue;

		imm = ((u64)insns[i + 1].imm << 32) | (u32)insns[i].imm;
		map = bpf_map_from_imm(prog, imm, &off, &type);
		if (map) {
			insns[i].src_reg = type;
			insns[i].imm = map->id;
			insns[i + 1].imm = off;
			continue;
		}
	}

	return insns;
}

Project: linux
File: syscall.c

static void __bpf_prog_put_noref(struct bpf_prog *prog, bool deferred)
{
	bpf_prog_kallsyms_del_all(prog);
	btf_put(prog->aux->btf);
	bpf_prog_free_linfo(prog);
	if (prog->aux->attach_btf)
		btf_put(prog->aux->attach_btf);

	if (deferred) {
		if (prog->aux->sleepable)
			call_rcu_tasks_trace(&prog->aux->rcu, __bpf_prog_put_rcu);
		else
			call_rcu(&prog->aux->rcu, __bpf_prog_put_rcu);
	} else {
		__bpf_prog_put_rcu(&prog->aux->rcu);
	}
}

Project: linux
File: syscall.c

static int bpf_enable_stats(union bpf_attr *attr)
{

	if (CHECK_ATTR(BPF_ENABLE_STATS))
		return -EINVAL;

	if (!capable(CAP_SYS_ADMIN))
		return -EPERM;

	switch (attr->enable_stats.type) {
	case BPF_STATS_RUN_TIME:
		return bpf_enable_runtime_stats();
	default:
		break;
	}
	return -EINVAL;
}

Project: linux
File: syscall.c

static int bpf_btf_load(const union bpf_attr *attr)
{
	if (CHECK_ATTR(BPF_BTF_LOAD))
		return -EINVAL;

	if (!bpf_capable())
		return -EPERM;

	return btf_new_fd(attr);
}

Project: linux
File: syscall.c

static int map_create(union bpf_attr *attr)
{
	int numa_node = bpf_map_attr_numa_node(attr);
	struct bpf_map *map;
	int f_flags;
	int err;

	err = CHECK_ATTR(BPF_MAP_CREATE);
	if (err)
		return -EINVAL;

	if (attr->btf_vmlinux_value_type_id) {
		if (attr->map_type != BPF_MAP_TYPE_STRUCT_OPS ||
		    attr->btf_key_type_id || attr->btf_value_type_id)
			return -EINVAL;
	} else if (attr->btf_key_type_id && !attr->btf_value_type_id) {
		return -EINVAL;
	}

	f_flags = bpf_get_file_flag(attr->map_flags);
	if (f_flags < 0)
		return f_flags;

	if (numa_node != NUMA_NO_NODE &&
	    ((unsigned int)numa_node >= nr_node_ids ||
	     !node_online(numa_node)))
		return -EINVAL;

	/* find map type and init map: hashtable vs rbtree vs bloom vs ... */
	map = find_and_alloc_map(attr);
	if (IS_ERR(map))
		return PTR_ERR(map);

	err = bpf_obj_name_cpy(map->name, attr->map_name,
			       sizeof(attr->map_name));
	if (err < 0)
		goto free_map;

	atomic64_set(&map->refcnt, 1);
	atomic64_set(&map->usercnt, 1);
	mutex_init(&map->freeze_mutex);

	map->spin_lock_off = -EINVAL;
	if (attr->btf_key_type_id || attr->btf_value_type_id ||
	    /* Even the map's value is a kernel's struct,
	     * the bpf_prog.o must have BTF to begin with
	     * to figure out the corresponding kernel's
	     * counter part.  Thus, attr->btf_fd has
	     * to be valid also.
	     */
	    attr->btf_vmlinux_value_type_id) {
		struct btf *btf;

		btf = btf_get_by_fd(attr->btf_fd);
		if (IS_ERR(btf)) {
			err = PTR_ERR(btf);
			goto free_map;
		}
		if (btf_is_kernel(btf)) {
			btf_put(btf);
			err = -EACCES;
			goto free_map;
		}
		map->btf = btf;

		if (attr->btf_value_type_id) {
			err = map_check_btf(map, btf, attr->btf_key_type_id,
					    attr->btf_value_type_id);
			if (err)
				goto free_map;
		}

		map->btf_key_type_id = attr->btf_key_type_id;
		map->btf_value_type_id = attr->btf_value_type_id;
		map->btf_vmlinux_value_type_id =
			attr->btf_vmlinux_value_type_id;
	}

	err = security_bpf_map_alloc(map);
	if (err)
		goto free_map;

	err = bpf_map_alloc_id(map);
	if (err)
		goto free_map_sec;

	bpf_map_save_memcg(map);

	err = bpf_map_new_fd(map, f_flags);
	if (err < 0) {
		/* failed to allocate fd.
		 * bpf_map_put_with_uref() is needed because the above
		 * bpf_map_alloc_id() has published the map
		 * to the userspace and the userspace may
		 * have refcnt-ed it through BPF_MAP_GET_FD_BY_ID.
		 */
		bpf_map_put_with_uref(map);
		return err;
	}

	return err;

free_map_sec:
	security_bpf_map_free(map);
free_map:
	btf_put(map->btf);
	map->ops->map_free(map);
	return err;
}

Project: linux
File: syscall.c

int bpf_link_prime(struct bpf_link *link, struct bpf_link_primer *primer)
{
	struct file *file;
	int fd, id;

	fd = get_unused_fd_flags(O_CLOEXEC);
	if (fd < 0)
		return fd;


	id = bpf_link_alloc_id(link);
	if (id < 0) {
		put_unused_fd(fd);
		return id;
	}

	file = anon_inode_getfile("bpf_link", &bpf_link_fops, link, O_CLOEXEC);
	if (IS_ERR(file)) {
		bpf_link_free_id(id);
		put_unused_fd(fd);
		return PTR_ERR(file);
	}

	primer->link = link;
	primer->file = file;
	primer->fd = fd;
	primer->id = id;
	return 0;
}

Project: linux
File: syscall.c

static struct bpf_map *__bpf_map_inc_not_zero(struct bpf_map *map, bool uref)
{
	int refold;

	refold = atomic64_fetch_add_unless(&map->refcnt, 1, 0);
	if (!refold)
		return ERR_PTR(-ENOENT);
	if (uref)
		atomic64_inc(&map->usercnt);

	return map;
}

Project: linux
File: syscall.c

static int map_update_elem(union bpf_attr *attr)
{
	void __user *ukey = u64_to_user_ptr(attr->key);
	void __user *uvalue = u64_to_user_ptr(attr->value);
	int ufd = attr->map_fd;
	struct bpf_map *map;
	void *key, *value;
	u32 value_size;
	struct fd f;
	int err;

	if (CHECK_ATTR(BPF_MAP_UPDATE_ELEM))
		return -EINVAL;

	f = fdget(ufd);
	map = __bpf_map_get(f);
	if (IS_ERR(map))
		return PTR_ERR(map);
	if (!(map_get_sys_perms(map, f) & FMODE_CAN_WRITE)) {
		err = -EPERM;
		goto err_put;
	}

	if ((attr->flags & BPF_F_LOCK) &&
	    !map_value_has_spin_lock(map)) {
		err = -EINVAL;
		goto err_put;
	}

	key = __bpf_copy_key(ukey, map->key_size);
	if (IS_ERR(key)) {
		err = PTR_ERR(key);
		goto err_put;
	}

	if (map->map_type == BPF_MAP_TYPE_PERCPU_HASH ||
	    map->map_type == BPF_MAP_TYPE_LRU_PERCPU_HASH ||
	    map->map_type == BPF_MAP_TYPE_PERCPU_ARRAY ||
	    map->map_type == BPF_MAP_TYPE_PERCPU_CGROUP_STORAGE)
		value_size = round_up(map->value_size, 8) * num_possible_cpus();
	else
		value_size = map->value_size;

	err = -ENOMEM;
	value = kmalloc(value_size, GFP_USER | __GFP_NOWARN);
	if (!value)
		goto free_key;

	err = -EFAULT;
	if (copy_from_user(value, uvalue, value_size) != 0)
		goto free_value;

	err = bpf_map_update_value(map, f, key, value, attr->flags);

free_value:
	kfree(value);
free_key:
	kfree(key);
err_put:
	fdput(f);
	return err;
}

Project: linux
File: syscall.c

static int bpf_stats_release(struct inode *inode, struct file *file)
{
	mutex_lock(&bpf_stats_enabled_mutex);
	static_key_slow_dec(&bpf_stats_enabled_key.key);
	mutex_unlock(&bpf_stats_enabled_mutex);
	return 0;
}

Project: linux
File: syscall.c

static int bpf_prog_alloc_id(struct bpf_prog *prog)
{
	int id;

	idr_preload(GFP_KERNEL);
	spin_lock_bh(&prog_idr_lock);
	id = idr_alloc_cyclic(&prog_idr, prog, 1, INT_MAX, GFP_ATOMIC);
	if (id > 0)
		prog->aux->id = id;
	spin_unlock_bh(&prog_idr_lock);
	idr_preload_end();

	/* id is in [1, INT_MAX) */
	if (WARN_ON_ONCE(!id))
		return -ENOSPC;

	return id > 0 ? 0 : id;
}

Project: linux
File: verifier.c

static int check_func_arg(struct bpf_verifier_env *env, u32 arg,
			  struct bpf_call_arg_meta *meta,
			  const struct bpf_func_proto *fn)
{
	u32 regno = BPF_REG_1 + arg;
	struct bpf_reg_state *regs = cur_regs(env), *reg = &regs[regno];
	enum bpf_arg_type arg_type = fn->arg_type[arg];
	enum bpf_reg_type type = reg->type;
	int err = 0;

	if (arg_type == ARG_DONTCARE)
		return 0;

	err = check_reg_arg(env, regno, SRC_OP);
	if (err)
		return err;

	if (arg_type == ARG_ANYTHING) {
		if (is_pointer_value(env, regno)) {
			verbose(env, "R%d leaks addr into helper function\n",
				regno);
			return -EACCES;
		}
		return 0;
	}

	if (type_is_pkt_pointer(type) &&
	    !may_access_direct_pkt_data(env, meta, BPF_READ)) {
		verbose(env, "helper access to the packet is not allowed\n");
		return -EACCES;
	}

	if (arg_type == ARG_PTR_TO_MAP_VALUE ||
	    arg_type == ARG_PTR_TO_UNINIT_MAP_VALUE ||
	    arg_type == ARG_PTR_TO_MAP_VALUE_OR_NULL) {
		err = resolve_map_arg_type(env, meta, &arg_type);
		if (err)
			return err;
	}

	if (register_is_null(reg) && arg_type_may_be_null(arg_type))
		/* A NULL register has a SCALAR_VALUE type, so skip
		 * type checking.
		 */
		goto skip_type_check;

	err = check_reg_type(env, regno, arg_type, fn->arg_btf_id[arg]);
	if (err)
		return err;

	if (type == PTR_TO_CTX) {
		err = check_ctx_reg(env, reg, regno);
		if (err < 0)
			return err;
	}

skip_type_check:
	if (reg->ref_obj_id) {
		if (meta->ref_obj_id) {
			verbose(env, "verifier internal error: more than one arg with ref_obj_id R%d %u %u\n",
				regno, reg->ref_obj_id,
				meta->ref_obj_id);
			return -EFAULT;
		}
		meta->ref_obj_id = reg->ref_obj_id;
	}

	if (arg_type == ARG_CONST_MAP_PTR) {
		/* bpf_map_xxx(map_ptr) call: remember that map_ptr */
		meta->map_ptr = reg->map_ptr;
	} else if (arg_type == ARG_PTR_TO_MAP_KEY) {
		/* bpf_map_xxx(..., map_ptr, ..., key) call:
		 * check that [key, key + map->key_size) are within
		 * stack limits and initialized
		 */
		if (!meta->map_ptr) {
			/* in function declaration map_ptr must come before
			 * map_key, so that it's verified and known before
			 * we have to check map_key here. Otherwise it means
			 * that kernel subsystem misconfigured verifier
			 */
			verbose(env, "invalid map_ptr to access map->key\n");
			return -EACCES;
		}
		err = check_helper_mem_access(env, regno,
					      meta->map_ptr->key_size, false,
					      NULL);
	} else if (arg_type == ARG_PTR_TO_MAP_VALUE ||
		   (arg_type == ARG_PTR_TO_MAP_VALUE_OR_NULL &&
		    !register_is_null(reg)) ||
		   arg_type == ARG_PTR_TO_UNINIT_MAP_VALUE) {
		/* bpf_map_xxx(..., map_ptr, ..., value) call:
		 * check [value, value + map->value_size) validity
		 */
		if (!meta->map_ptr) {
			/* kernel subsystem misconfigured verifier */
			verbose(env, "invalid map_ptr to access map->value\n");
			return -EACCES;
		}
		meta->raw_mode = (arg_type == ARG_PTR_TO_UNINIT_MAP_VALUE);
		err = check_helper_mem_access(env, regno,
					      meta->map_ptr->value_size, false,
					      meta);
	} else if (arg_type == ARG_PTR_TO_PERCPU_BTF_ID) {
		if (!reg->btf_id) {
			verbose(env, "Helper has invalid btf_id in R%d\n", regno);
			return -EACCES;
		}
		meta->ret_btf = reg->btf;
		meta->ret_btf_id = reg->btf_id;
	} else if (arg_type == ARG_PTR_TO_SPIN_LOCK) {
		if (meta->func_id == BPF_FUNC_spin_lock) {
			if (process_spin_lock(env, regno, true))
				return -EACCES;
		} else if (meta->func_id == BPF_FUNC_spin_unlock) {
			if (process_spin_lock(env, regno, false))
				return -EACCES;
		} else {
			verbose(env, "verifier internal error\n");
			return -EFAULT;
		}
	} else if (arg_type_is_mem_ptr(arg_type)) {
		/* The access to this pointer is only checked when we hit the
		 * next is_mem_size argument below.
		 */
		meta->raw_mode = (arg_type == ARG_PTR_TO_UNINIT_MEM);
	} else if (arg_type_is_mem_size(arg_type)) {
		bool zero_size_allowed = (arg_type == ARG_CONST_SIZE_OR_ZERO);

		/* This is used to refine r0 return value bounds for helpers
		 * that enforce this value as an upper bound on return values.
		 * See do_refine_retval_range() for helpers that can refine
		 * the return value. C type of helper is u32 so we pull register
		 * bound from umax_value however, if negative verifier errors
		 * out. Only upper bounds can be learned because retval is an
		 * int type and negative retvals are allowed.
		 */
		meta->msize_max_value = reg->umax_value;

		/* The register is SCALAR_VALUE; the access check
		 * happens using its boundaries.
		 */
		if (!tnum_is_const(reg->var_off))
			/* For unprivileged variable accesses, disable raw
			 * mode so that the program is required to
			 * initialize all the memory that the helper could
			 * just partially fill up.
			 */
			meta = NULL;

		if (reg->smin_value < 0) {
			verbose(env, "R%d min value is negative, either use unsigned or 'var &= const'\n",
				regno);
			return -EACCES;
		}

		if (reg->umin_value == 0) {
			err = check_helper_mem_access(env, regno - 1, 0,
						      zero_size_allowed,
						      meta);
			if (err)
				return err;
		}

		if (reg->umax_value >= BPF_MAX_VAR_SIZ) {
			verbose(env, "R%d unbounded memory access, use 'var &= const' or 'if (var < const)'\n",
				regno);
			return -EACCES;
		}
		err = check_helper_mem_access(env, regno - 1,
					      reg->umax_value,
					      zero_size_allowed, meta);
		if (!err)
			err = mark_chain_precision(env, regno);
	} else if (arg_type_is_alloc_size(arg_type)) {
		if (!tnum_is_const(reg->var_off)) {
			verbose(env, "R%d is not a known constant'\n",
				regno);
			return -EACCES;
		}
		meta->mem_size = reg->var_off.value;
	} else if (arg_type_is_int_ptr(arg_type)) {
		int size = int_ptr_type_to_size(arg_type);

		err = check_helper_mem_access(env, regno, size, false, meta);
		if (err)
			return err;
		err = check_ptr_alignment(env, reg, 0, size, true);
	}

	return err;
}

Project: linux
File: syscall.c

static int bpf_map_get_fd_by_id(const union bpf_attr *attr)
{
	struct bpf_map *map;
	u32 id = attr->map_id;
	int f_flags;
	int fd;

	if (CHECK_ATTR(BPF_MAP_GET_FD_BY_ID) ||
	    attr->open_flags & ~BPF_OBJ_FLAG_MASK)
		return -EINVAL;

	if (!capable(CAP_SYS_ADMIN))
		return -EPERM;

	f_flags = bpf_get_file_flag(attr->open_flags);
	if (f_flags < 0)
		return f_flags;

	spin_lock_bh(&map_idr_lock);
	map = idr_find(&map_idr, id);
	if (map)
		map = __bpf_map_inc_not_zero(map, true);
	else
		map = ERR_PTR(-ENOENT);
	spin_unlock_bh(&map_idr_lock);

	if (IS_ERR(map))
		return PTR_ERR(map);

	fd = bpf_map_new_fd(map, f_flags);
	if (fd < 0)
		bpf_map_put_with_uref(map);

	return fd;
}

Project: linux
File: syscall.c

static void *__bpf_map_area_alloc(u64 size, int numa_node, bool mmapable)
{
	/* We really just want to fail instead of triggering OOM killer
	 * under memory pressure, therefore we set __GFP_NORETRY to kmalloc,
	 * which is used for lower order allocation requests.
	 *
	 * It has been observed that higher order allocation requests done by
	 * vmalloc with __GFP_NORETRY being set might fail due to not trying
	 * to reclaim memory from the page cache, thus we set
	 * __GFP_RETRY_MAYFAIL to avoid such situations.
	 */

	const gfp_t gfp = __GFP_NOWARN | __GFP_ZERO | __GFP_ACCOUNT;
	unsigned int flags = 0;
	unsigned long align = 1;
	void *area;

	if (size >= SIZE_MAX)
		return NULL;

	/* kmalloc()'ed memory can't be mmap()'ed */
	if (mmapable) {
		BUG_ON(!PAGE_ALIGNED(size));
		align = SHMLBA;
		flags = VM_USERMAP;
	} else if (size <= (PAGE_SIZE << PAGE_ALLOC_COSTLY_ORDER)) {
		area = kmalloc_node(size, gfp | GFP_USER | __GFP_NORETRY,
				    numa_node);
		if (area != NULL)
			return area;
	}

	return __vmalloc_node_range(size, align, VMALLOC_START, VMALLOC_END,
			gfp | GFP_KERNEL | __GFP_RETRY_MAYFAIL, PAGE_KERNEL,
			flags, numa_node, __builtin_return_address(0));
}

Project: linux
File: syscall.c

static int bpf_btf_get_fd_by_id(const union bpf_attr *attr)
{
	if (CHECK_ATTR(BPF_BTF_GET_FD_BY_ID))
		return -EINVAL;

	if (!capable(CAP_SYS_ADMIN))
		return -EPERM;

	return btf_get_fd_by_id(attr->btf_id);
}

Project: linux
File: syscall.c

struct bpf_map *bpf_map_inc_not_zero(struct bpf_map *map)
{
	spin_lock_bh(&map_idr_lock);
	map = __bpf_map_inc_not_zero(map, false);
	spin_unlock_bh(&map_idr_lock);

	return map;
}

Project: linux
File: syscall.c

int generic_map_delete_batch(struct bpf_map *map,
			     const union bpf_attr *attr,
			     union bpf_attr __user *uattr)
{
	void __user *keys = u64_to_user_ptr(attr->batch.keys);
	u32 cp, max_count;
	int err = 0;
	void *key;

	if (attr->batch.elem_flags & ~BPF_F_LOCK)
		return -EINVAL;

	if ((attr->batch.elem_flags & BPF_F_LOCK) &&
	    !map_value_has_spin_lock(map)) {
		return -EINVAL;
	}

	max_count = attr->batch.count;
	if (!max_count)
		return 0;

	key = kmalloc(map->key_size, GFP_USER | __GFP_NOWARN);
	if (!key)
		return -ENOMEM;

	for (cp = 0; cp < max_count; cp++) {
		err = -EFAULT;
		if (copy_from_user(key, keys + cp * map->key_size,
				   map->key_size))
			break;

		if (bpf_map_is_dev_bound(map)) {
			err = bpf_map_offload_delete_elem(map, key);
			break;
		}

		bpf_disable_instrumentation();
		rcu_read_lock();
		err = map->ops->map_delete_elem(map, key);
		rcu_read_unlock();
		bpf_enable_instrumentation();
		maybe_wait_bpf_programs(map);
		if (err)
			break;
	}
	if (copy_to_user(&uattr->batch.count, &cp, sizeof(cp)))
		err = -EFAULT;

	kfree(key);
	return err;
}

Project: linux
File: syscall.c

static int bpf_btf_get_info_by_fd(struct file *file,
				  struct btf *btf,
				  const union bpf_attr *attr,
				  union bpf_attr __user *uattr)
{
	struct bpf_btf_info __user *uinfo = u64_to_user_ptr(attr->info.info);
	u32 info_len = attr->info.info_len;
	int err;

	err = bpf_check_uarg_tail_zero(uinfo, sizeof(*uinfo), info_len);
	if (err)
		return err;

	return btf_get_info_by_fd(btf, attr, uattr);
}

Project: linux
File: syscall.c

static void bpf_prog_show_fdinfo(struct seq_file *m, struct file *filp)
{
	const struct bpf_prog *prog = filp->private_data;
	char prog_tag[sizeof(prog->tag) * 2 + 1] = { };
	struct bpf_prog_stats stats;

	bpf_prog_get_stats(prog, &stats);
	bin2hex(prog_tag, prog->tag, sizeof(prog->tag));
	seq_printf(m,
		   "prog_type:\t%u\n"
		   "prog_jited:\t%u\n"
		   "prog_tag:\t%s\n"
		   "memlock:\t%llu\n"
		   "prog_id:\t%u\n"
		   "run_time_ns:\t%llu\n"
		   "run_cnt:\t%llu\n"
		   "recursion_misses:\t%llu\n",
		   prog->type,
		   prog->jited,
		   prog_tag,
		   prog->pages * 1ULL << PAGE_SHIFT,
		   prog->aux->id,
		   stats.nsecs,
		   stats.cnt,
		   stats.misses);
}

Project: linux
File: syscall.c

static u32 bpf_map_value_size(const struct bpf_map *map)
{
	if (map->map_type == BPF_MAP_TYPE_PERCPU_HASH ||
	    map->map_type == BPF_MAP_TYPE_LRU_PERCPU_HASH ||
	    map->map_type == BPF_MAP_TYPE_PERCPU_ARRAY ||
	    map->map_type == BPF_MAP_TYPE_PERCPU_CGROUP_STORAGE)
		return round_up(map->value_size, 8) * num_possible_cpus();
	else if (IS_FD_MAP(map))
		return sizeof(u32);
	else
		return  map->value_size;
}

Project: linux
File: syscall.c

static int bpf_prog_bind_map(union bpf_attr *attr)
{
	struct bpf_prog *prog;
	struct bpf_map *map;
	struct bpf_map **used_maps_old, **used_maps_new;
	int i, ret = 0;

	if (CHECK_ATTR(BPF_PROG_BIND_MAP))
		return -EINVAL;

	if (attr->prog_bind_map.flags)
		return -EINVAL;

	prog = bpf_prog_get(attr->prog_bind_map.prog_fd);
	if (IS_ERR(prog))
		return PTR_ERR(prog);

	map = bpf_map_get(attr->prog_bind_map.map_fd);
	if (IS_ERR(map)) {
		ret = PTR_ERR(map);
		goto out_prog_put;
	}

	mutex_lock(&prog->aux->used_maps_mutex);

	used_maps_old = prog->aux->used_maps;

	for (i = 0; i < prog->aux->used_map_cnt; i++)
		if (used_maps_old[i] == map) {
			bpf_map_put(map);
			goto out_unlock;
		}

	used_maps_new = kmalloc_array(prog->aux->used_map_cnt + 1,
				      sizeof(used_maps_new[0]),
				      GFP_KERNEL);
	if (!used_maps_new) {
		ret = -ENOMEM;
		goto out_unlock;
	}

	memcpy(used_maps_new, used_maps_old,
	       sizeof(used_maps_old[0]) * prog->aux->used_map_cnt);
	used_maps_new[prog->aux->used_map_cnt] = map;

	prog->aux->used_map_cnt++;
	prog->aux->used_maps = used_maps_new;

	kfree(used_maps_old);

out_unlock:
	mutex_unlock(&prog->aux->used_maps_mutex);

	if (ret)
		bpf_map_put(map);
out_prog_put:
	bpf_prog_put(prog);
	return ret;
}

Project: linux
File: syscall.c

static int bpf_map_get_info_by_fd(struct file *file,
				  struct bpf_map *map,
				  const union bpf_attr *attr,
				  union bpf_attr __user *uattr)
{
	struct bpf_map_info __user *uinfo = u64_to_user_ptr(attr->info.info);
	struct bpf_map_info info;
	u32 info_len = attr->info.info_len;
	int err;

	err = bpf_check_uarg_tail_zero(uinfo, sizeof(info), info_len);
	if (err)
		return err;
	info_len = min_t(u32, sizeof(info), info_len);

	memset(&info, 0, sizeof(info));
	info.type = map->map_type;
	info.id = map->id;
	info.key_size = map->key_size;
	info.value_size = map->value_size;
	info.max_entries = map->max_entries;
	info.map_flags = map->map_flags;
	memcpy(info.name, map->name, sizeof(map->name));

	if (map->btf) {
		info.btf_id = btf_obj_id(map->btf);
		info.btf_key_type_id = map->btf_key_type_id;
		info.btf_value_type_id = map->btf_value_type_id;
	}
	info.btf_vmlinux_value_type_id = map->btf_vmlinux_value_type_id;

	if (bpf_map_is_dev_bound(map)) {
		err = bpf_map_offload_info_fill(&info, map);
		if (err)
			return err;
	}

	if (copy_to_user(uinfo, &info, info_len) ||
	    put_user(info_len, &uattr->info.info_len))
		return -EFAULT;

	return 0;
}

Project: linux
File: syscall.c

static int bpf_map_copy_value(struct bpf_map *map, void *key, void *value,
			      __u64 flags)
{
	void *ptr;
	int err;

	if (bpf_map_is_dev_bound(map))
		return bpf_map_offload_lookup_elem(map, key, value);

	bpf_disable_instrumentation();
	if (map->map_type == BPF_MAP_TYPE_PERCPU_HASH ||
	    map->map_type == BPF_MAP_TYPE_LRU_PERCPU_HASH) {
		err = bpf_percpu_hash_copy(map, key, value);
	} else if (map->map_type == BPF_MAP_TYPE_PERCPU_ARRAY) {
		err = bpf_percpu_array_copy(map, key, value);
	} else if (map->map_type == BPF_MAP_TYPE_PERCPU_CGROUP_STORAGE) {
		err = bpf_percpu_cgroup_storage_copy(map, key, value);
	} else if (map->map_type == BPF_MAP_TYPE_STACK_TRACE) {
		err = bpf_stackmap_copy(map, key, value);
	} else if (IS_FD_ARRAY(map) || IS_FD_PROG_ARRAY(map)) {
		err = bpf_fd_array_map_lookup_elem(map, key, value);
	} else if (IS_FD_HASH(map)) {
		err = bpf_fd_htab_map_lookup_elem(map, key, value);
	} else if (map->map_type == BPF_MAP_TYPE_REUSEPORT_SOCKARRAY) {
		err = bpf_fd_reuseport_array_lookup_elem(map, key, value);
	} else if (map->map_type == BPF_MAP_TYPE_QUEUE ||
		   map->map_type == BPF_MAP_TYPE_STACK) {
		err = map->ops->map_peek_elem(map, value);
	} else if (map->map_type == BPF_MAP_TYPE_STRUCT_OPS) {
		/* struct_ops map requires directly updating "value" */
		err = bpf_struct_ops_map_sys_lookup_elem(map, key, value);
	} else {
		rcu_read_lock();
		if (map->ops->map_lookup_elem_sys_only)
			ptr = map->ops->map_lookup_elem_sys_only(map, key);
		else
			ptr = map->ops->map_lookup_elem(map, key);
		if (IS_ERR(ptr)) {
			err = PTR_ERR(ptr);
		} else if (!ptr) {
			err = -ENOENT;
		} else {
			err = 0;
			if (flags & BPF_F_LOCK)
				/* lock 'ptr' and copy everything but lock */
				copy_map_value_locked(map, value, ptr, true);
			else
				copy_map_value(map, value, ptr);
			/* mask lock, since value wasn't zero inited */
			check_and_init_map_lock(map, value);
		}
		rcu_read_unlock();
	}

	bpf_enable_instrumentation();
	maybe_wait_bpf_programs(map);

	return err;
}

Project: linux
File: verifier.c

static int check_helper_call(struct bpf_verifier_env *env, int func_id, int insn_idx)
{
	const struct bpf_func_proto *fn = NULL;
	struct bpf_reg_state *regs;
	struct bpf_call_arg_meta meta;
	bool changes_data;
	int i, err;

	/* find function prototype */
	if (func_id < 0 || func_id >= __BPF_FUNC_MAX_ID) {
		verbose(env, "invalid func %s#%d\n", func_id_name(func_id),
			func_id);
		return -EINVAL;
	}

	if (env->ops->get_func_proto)
		fn = env->ops->get_func_proto(func_id, env->prog);
	if (!fn) {
		verbose(env, "unknown func %s#%d\n", func_id_name(func_id),
			func_id);
		return -EINVAL;
	}

	/* eBPF programs must be GPL compatible to use GPL-ed functions */
	if (!env->prog->gpl_compatible && fn->gpl_only) {
		verbose(env, "cannot call GPL-restricted function from non-GPL compatible program\n");
		return -EINVAL;
	}

	if (fn->allowed && !fn->allowed(env->prog)) {
		verbose(env, "helper call is not allowed in probe\n");
		return -EINVAL;
	}

	/* With LD_ABS/IND some JITs save/restore skb from r1. */
	changes_data = bpf_helper_changes_pkt_data(fn->func);
	if (changes_data && fn->arg1_type != ARG_PTR_TO_CTX) {
		verbose(env, "kernel subsystem misconfigured func %s#%d: r1 != ctx\n",
			func_id_name(func_id), func_id);
		return -EINVAL;
	}

	memset(&meta, 0, sizeof(meta));
	meta.pkt_access = fn->pkt_access;

	err = check_func_proto(fn, func_id);
	if (err) {
		verbose(env, "kernel subsystem misconfigured func %s#%d\n",
			func_id_name(func_id), func_id);
		return err;
	}

	meta.func_id = func_id;
	/* check args */
	for (i = 0; i < 5; i++) {
		err = check_func_arg(env, i, &meta, fn);
		if (err)
			return err;
	}

	err = record_func_map(env, &meta, func_id, insn_idx);
	if (err)
		return err;

	err = record_func_key(env, &meta, func_id, insn_idx);
	if (err)
		return err;

	/* Mark slots with STACK_MISC in case of raw mode, stack offset
	 * is inferred from register state.
	 */
	for (i = 0; i < meta.access_size; i++) {
		err = check_mem_access(env, insn_idx, meta.regno, i, BPF_B,
				       BPF_WRITE, -1, false);
		if (err)
			return err;
	}

	if (func_id == BPF_FUNC_tail_call) {
		err = check_reference_leak(env);
		if (err) {
			verbose(env, "tail_call would lead to reference leak\n");
			return err;
		}
	} else if (is_release_function(func_id)) {
		err = release_reference(env, meta.ref_obj_id);
		if (err) {
			verbose(env, "func %s#%d reference has not been acquired before\n",
				func_id_name(func_id), func_id);
			return err;
		}
	}

	regs = cur_regs(env);

	/* check that flags argument in get_local_storage(map, flags) is 0,
	 * this is required because get_local_storage() can't return an error.
	 */
	if (func_id == BPF_FUNC_get_local_storage &&
	    !register_is_null(&regs[BPF_REG_2])) {
		verbose(env, "get_local_storage() doesn't support non-zero flags\n");
		return -EINVAL;
	}

	/* reset caller saved regs */
	for (i = 0; i < CALLER_SAVED_REGS; i++) {
		mark_reg_not_init(env, regs, caller_saved[i]);
		check_reg_arg(env, caller_saved[i], DST_OP_NO_MARK);
	}

	/* helper call returns 64-bit value. */
	regs[BPF_REG_0].subreg_def = DEF_NOT_SUBREG;

	/* update return register (already marked as written above) */
	if (fn->ret_type == RET_INTEGER) {
		/* sets type to SCALAR_VALUE */
		mark_reg_unknown(env, regs, BPF_REG_0);
	} else if (fn->ret_type == RET_VOID) {
		regs[BPF_REG_0].type = NOT_INIT;
	} else if (fn->ret_type == RET_PTR_TO_MAP_VALUE_OR_NULL ||
		   fn->ret_type == RET_PTR_TO_MAP_VALUE) {
		/* There is no offset yet applied, variable or fixed */
		mark_reg_known_zero(env, regs, BPF_REG_0);
		/* remember map_ptr, so that check_map_access()
		 * can check 'value_size' boundary of memory access
		 * to map element returned from bpf_map_lookup_elem()
		 */
		if (meta.map_ptr == NULL) {
			verbose(env,
				"kernel subsystem misconfigured verifier\n");
			return -EINVAL;
		}
		regs[BPF_REG_0].map_ptr = meta.map_ptr;
		if (fn->ret_type == RET_PTR_TO_MAP_VALUE) {
			regs[BPF_REG_0].type = PTR_TO_MAP_VALUE;
			if (map_value_has_spin_lock(meta.map_ptr))
				regs[BPF_REG_0].id = ++env->id_gen;
		} else {
			regs[BPF_REG_0].type = PTR_TO_MAP_VALUE_OR_NULL;
		}
	} else if (fn->ret_type == RET_PTR_TO_SOCKET_OR_NULL) {
		mark_reg_known_zero(env, regs, BPF_REG_0);
		regs[BPF_REG_0].type = PTR_TO_SOCKET_OR_NULL;
	} else if (fn->ret_type == RET_PTR_TO_SOCK_COMMON_OR_NULL) {
		mark_reg_known_zero(env, regs, BPF_REG_0);
		regs[BPF_REG_0].type = PTR_TO_SOCK_COMMON_OR_NULL;
	} else if (fn->ret_type == RET_PTR_TO_TCP_SOCK_OR_NULL) {
		mark_reg_known_zero(env, regs, BPF_REG_0);
		regs[BPF_REG_0].type = PTR_TO_TCP_SOCK_OR_NULL;
	} else if (fn->ret_type == RET_PTR_TO_ALLOC_MEM_OR_NULL) {
		mark_reg_known_zero(env, regs, BPF_REG_0);
		regs[BPF_REG_0].type = PTR_TO_MEM_OR_NULL;
		regs[BPF_REG_0].mem_size = meta.mem_size;
	} else if (fn->ret_type == RET_PTR_TO_MEM_OR_BTF_ID_OR_NULL ||
		   fn->ret_type == RET_PTR_TO_MEM_OR_BTF_ID) {
		const struct btf_type *t;

		mark_reg_known_zero(env, regs, BPF_REG_0);
		t = btf_type_skip_modifiers(meta.ret_btf, meta.ret_btf_id, NULL);
		if (!btf_type_is_struct(t)) {
			u32 tsize;
			const struct btf_type *ret;
			const char *tname;

			/* resolve the type size of ksym. */
			ret = btf_resolve_size(meta.ret_btf, t, &tsize);
			if (IS_ERR(ret)) {
				tname = btf_name_by_offset(meta.ret_btf, t->name_off);
				verbose(env, "unable to resolve the size of type '%s': %ld\n",
					tname, PTR_ERR(ret));
				return -EINVAL;
			}
			regs[BPF_REG_0].type =
				fn->ret_type == RET_PTR_TO_MEM_OR_BTF_ID ?
				PTR_TO_MEM : PTR_TO_MEM_OR_NULL;
			regs[BPF_REG_0].mem_size = tsize;
		} else {
			regs[BPF_REG_0].type =
				fn->ret_type == RET_PTR_TO_MEM_OR_BTF_ID ?
				PTR_TO_BTF_ID : PTR_TO_BTF_ID_OR_NULL;
			regs[BPF_REG_0].btf = meta.ret_btf;
			regs[BPF_REG_0].btf_id = meta.ret_btf_id;
		}
	} else if (fn->ret_type == RET_PTR_TO_BTF_ID_OR_NULL ||
		   fn->ret_type == RET_PTR_TO_BTF_ID) {
		int ret_btf_id;

		mark_reg_known_zero(env, regs, BPF_REG_0);
		regs[BPF_REG_0].type = fn->ret_type == RET_PTR_TO_BTF_ID ?
						     PTR_TO_BTF_ID :
						     PTR_TO_BTF_ID_OR_NULL;
		ret_btf_id = *fn->ret_btf_id;
		if (ret_btf_id == 0) {
			verbose(env, "invalid return type %d of func %s#%d\n",
				fn->ret_type, func_id_name(func_id), func_id);
			return -EINVAL;
		}
		/* current BPF helper definitions are only coming from
		 * built-in code with type IDs from  vmlinux BTF
		 */
		regs[BPF_REG_0].btf = btf_vmlinux;
		regs[BPF_REG_0].btf_id = ret_btf_id;
	} else {
		verbose(env, "unknown return type %d of func %s#%d\n",
			fn->ret_type, func_id_name(func_id), func_id);
		return -EINVAL;
	}

	if (reg_type_may_be_null(regs[BPF_REG_0].type))
		regs[BPF_REG_0].id = ++env->id_gen;

	if (is_ptr_cast_function(func_id)) {
		/* For release_reference() */
		regs[BPF_REG_0].ref_obj_id = meta.ref_obj_id;
	} else if (is_acquire_function(func_id, meta.map_ptr)) {
		int id = acquire_reference_state(env, insn_idx);

		if (id < 0)
			return id;
		/* For mark_ptr_or_null_reg() */
		regs[BPF_REG_0].id = id;
		/* For release_reference() */
		regs[BPF_REG_0].ref_obj_id = id;
	}

	do_refine_retval_range(regs, fn->ret_type, func_id, &meta);

	err = check_map_func_compatibility(env, meta.map_ptr, func_id);
	if (err)
		return err;

	if ((func_id == BPF_FUNC_get_stack ||
	     func_id == BPF_FUNC_get_task_stack) &&
	    !env->prog->has_callchain_buf) {
		const char *err_str;

#ifdef CONFIG_PERF_EVENTS
		err = get_callchain_buffers(sysctl_perf_event_max_stack);
		err_str = "cannot get callchain buffer for func %s#%d\n";
#else
		err = -ENOTSUPP;
		err_str = "func %s#%d not supported without CONFIG_PERF_EVENTS\n";
#endif
		if (err) {
			verbose(env, err_str, func_id_name(func_id), func_id);
			return err;
		}

		env->prog->has_callchain_buf = true;
	}

	if (func_id == BPF_FUNC_get_stackid || func_id == BPF_FUNC_get_stack)
		env->prog->call_get_stack = true;

	if (changes_data)
		clear_all_pkt_pointers(env);
	return 0;
}

Project: linux
File: syscall.c

void bpf_map_inc(struct bpf_map *map)
{
	atomic64_inc(&map->refcnt);
}

Project: linux
File: syscall.c

void bpf_prog_add(struct bpf_prog *prog, int i)
{
	atomic64_add(i, &prog->aux->refcnt);
}

Project: linux
File: syscall.c

SYSCALL_DEFINE3(bpf, int, cmd, union bpf_attr __user *, uattr, unsigned int, size)
{
	union bpf_attr attr;
	int err;

	if (sysctl_unprivileged_bpf_disabled && !bpf_capable())
		return -EPERM;

	err = bpf_check_uarg_tail_zero(uattr, sizeof(attr), size);
	if (err)
		return err;
	size = min_t(u32, size, sizeof(attr));

	/* copy attributes from user space, may be less than sizeof(bpf_attr) */
	memset(&attr, 0, sizeof(attr));
	if (copy_from_user(&attr, uattr, size) != 0)
		return -EFAULT;

	err = security_bpf(cmd, &attr, size);
	if (err < 0)
		return err;

	switch (cmd) {
	case BPF_MAP_CREATE:
		err = map_create(&attr);
		break;
	case BPF_MAP_LOOKUP_ELEM:
		err = map_lookup_elem(&attr);
		break;
	case BPF_MAP_UPDATE_ELEM:
		err = map_update_elem(&attr);
		break;
	case BPF_MAP_DELETE_ELEM:
		err = map_delete_elem(&attr);
		break;
	case BPF_MAP_GET_NEXT_KEY:
		err = map_get_next_key(&attr);
		break;
	case BPF_MAP_FREEZE:
		err = map_freeze(&attr);
		break;
	case BPF_PROG_LOAD:
		err = bpf_prog_load(&attr, uattr);
		break;
	case BPF_OBJ_PIN:
		err = bpf_obj_pin(&attr);
		break;
	case BPF_OBJ_GET:
		err = bpf_obj_get(&attr);
		break;
	case BPF_PROG_ATTACH:
		err = bpf_prog_attach(&attr);
		break;
	case BPF_PROG_DETACH:
		err = bpf_prog_detach(&attr);
		break;
	case BPF_PROG_QUERY:
		err = bpf_prog_query(&attr, uattr);
		break;
	case BPF_PROG_TEST_RUN:
		err = bpf_prog_test_run(&attr, uattr);
		break;
	case BPF_PROG_GET_NEXT_ID:
		err = bpf_obj_get_next_id(&attr, uattr,
					  &prog_idr, &prog_idr_lock);
		break;
	case BPF_MAP_GET_NEXT_ID:
		err = bpf_obj_get_next_id(&attr, uattr,
					  &map_idr, &map_idr_lock);
		break;
	case BPF_BTF_GET_NEXT_ID:
		err = bpf_obj_get_next_id(&attr, uattr,
					  &btf_idr, &btf_idr_lock);
		break;
	case BPF_PROG_GET_FD_BY_ID:
		err = bpf_prog_get_fd_by_id(&attr);
		break;
	case BPF_MAP_GET_FD_BY_ID:
		err = bpf_map_get_fd_by_id(&attr);
		break;
	case BPF_OBJ_GET_INFO_BY_FD:
		err = bpf_obj_get_info_by_fd(&attr, uattr);
		break;
	case BPF_RAW_TRACEPOINT_OPEN:
		err = bpf_raw_tracepoint_open(&attr);
		break;
	case BPF_BTF_LOAD:
		err = bpf_btf_load(&attr);
		break;
	case BPF_BTF_GET_FD_BY_ID:
		err = bpf_btf_get_fd_by_id(&attr);
		break;
	case BPF_TASK_FD_QUERY:
		err = bpf_task_fd_query(&attr, uattr);
		break;
	case BPF_MAP_LOOKUP_AND_DELETE_ELEM:
		err = map_lookup_and_delete_elem(&attr);
		break;
	case BPF_MAP_LOOKUP_BATCH:
		err = bpf_map_do_batch(&attr, uattr, BPF_MAP_LOOKUP_BATCH);
		break;
	case BPF_MAP_LOOKUP_AND_DELETE_BATCH:
		err = bpf_map_do_batch(&attr, uattr,
				       BPF_MAP_LOOKUP_AND_DELETE_BATCH);
		break;
	case BPF_MAP_UPDATE_BATCH:
		err = bpf_map_do_batch(&attr, uattr, BPF_MAP_UPDATE_BATCH);
		break;
	case BPF_MAP_DELETE_BATCH:
		err = bpf_map_do_batch(&attr, uattr, BPF_MAP_DELETE_BATCH);
		break;
	case BPF_LINK_CREATE:
		err = link_create(&attr);
		break;
	case BPF_LINK_UPDATE:
		err = link_update(&attr);
		break;
	case BPF_LINK_GET_FD_BY_ID:
		err = bpf_link_get_fd_by_id(&attr);
		break;
	case BPF_LINK_GET_NEXT_ID:
		err = bpf_obj_get_next_id(&attr, uattr,
					  &link_idr, &link_idr_lock);
		break;
	case BPF_ENABLE_STATS:
		err = bpf_enable_stats(&attr);
		break;
	case BPF_ITER_CREATE:
		err = bpf_iter_create(&attr);
		break;
	case BPF_LINK_DETACH:
		err = link_detach(&attr);
		break;
	case BPF_PROG_BIND_MAP:
		err = bpf_prog_bind_map(&attr);
		break;
	default:
		err = -EINVAL;
		break;
	}

	return err;
}

Project: linux
File: syscall.c

static int bpf_iter_create(union bpf_attr *attr)
{
	struct bpf_link *link;
	int err;

	if (CHECK_ATTR(BPF_ITER_CREATE))
		return -EINVAL;

	if (attr->iter_create.flags)
		return -EINVAL;

	link = bpf_link_get_from_fd(attr->iter_create.link_fd);
	if (IS_ERR(link))
		return PTR_ERR(link);

	err = bpf_iter_new_fd(link);
	bpf_link_put(link);

	return err;
}

Project: linux
File: syscall.c

struct bpf_map *bpf_map_get_curr_or_next(u32 *id)
{
	struct bpf_map *map;

	spin_lock_bh(&map_idr_lock);
again:
	map = idr_get_next(&map_idr, id);
	if (map) {
		map = __bpf_map_inc_not_zero(map, false);
		if (IS_ERR(map)) {
			(*id)++;
			goto again;
		}
	}
	spin_unlock_bh(&map_idr_lock);

	return map;
}

Project: linux
File: syscall.c

static void bpf_raw_tp_link_release(struct bpf_link *link)
{
	struct bpf_raw_tp_link *raw_tp =
		container_of(link, struct bpf_raw_tp_link, link);

	bpf_probe_unregister(raw_tp->btp, raw_tp->link.prog);
	bpf_put_raw_tracepoint(raw_tp->btp);
}

Project: linux
File: syscall.c

static void bpf_map_show_fdinfo(struct seq_file *m, struct file *filp)
{
	const struct bpf_map *map = filp->private_data;
	const struct bpf_array *array;
	u32 type = 0, jited = 0;

	if (map->map_type == BPF_MAP_TYPE_PROG_ARRAY) {
		array = container_of(map, struct bpf_array, map);
		type  = array->aux->type;
		jited = array->aux->jited;
	}

	seq_printf(m,
		   "map_type:\t%u\n"
		   "key_size:\t%u\n"
		   "value_size:\t%u\n"
		   "max_entries:\t%u\n"
		   "map_flags:\t%#x\n"
		   "memlock:\t%lu\n"
		   "map_id:\t%u\n"
		   "frozen:\t%u\n",
		   map->map_type,
		   map->key_size,
		   map->value_size,
		   map->max_entries,
		   map->map_flags,
		   bpf_map_memory_footprint(map),
		   map->id,
		   READ_ONCE(map->frozen));
	if (type) {
		seq_printf(m, "owner_prog_type:\t%u\n", type);
		seq_printf(m, "owner_jited:\t%u\n", jited);
	}
}

Project: linux
File: syscall.c

static int map_lookup_and_delete_elem(union bpf_attr *attr)
{
	void __user *ukey = u64_to_user_ptr(attr->key);
	void __user *uvalue = u64_to_user_ptr(attr->value);
	int ufd = attr->map_fd;
	struct bpf_map *map;
	void *key, *value;
	u32 value_size;
	struct fd f;
	int err;

	if (CHECK_ATTR(BPF_MAP_LOOKUP_AND_DELETE_ELEM))
		return -EINVAL;

	f = fdget(ufd);
	map = __bpf_map_get(f);
	if (IS_ERR(map))
		return PTR_ERR(map);
	if (!(map_get_sys_perms(map, f) & FMODE_CAN_READ) ||
	    !(map_get_sys_perms(map, f) & FMODE_CAN_WRITE)) {
		err = -EPERM;
		goto err_put;
	}

	key = __bpf_copy_key(ukey, map->key_size);
	if (IS_ERR(key)) {
		err = PTR_ERR(key);
		goto err_put;
	}

	value_size = map->value_size;

	err = -ENOMEM;
	value = kmalloc(value_size, GFP_USER | __GFP_NOWARN);
	if (!value)
		goto free_key;

	if (map->map_type == BPF_MAP_TYPE_QUEUE ||
	    map->map_type == BPF_MAP_TYPE_STACK) {
		err = map->ops->map_pop_elem(map, value);
	} else {
		err = -ENOTSUPP;
	}

	if (err)
		goto free_value;

	if (copy_to_user(uvalue, value, value_size) != 0) {
		err = -EFAULT;
		goto free_value;
	}

	err = 0;

free_value:
	kfree(value);
free_key:
	kfree(key);
err_put:
	fdput(f);
	return err;
}

Project: linux
File: syscall.c

static void *__bpf_copy_key(void __user *ukey, u64 key_size)
{
	if (key_size)
		return memdup_user(ukey, key_size);

	if (ukey)
		return ERR_PTR(-EINVAL);

	return NULL;
}

Project: linux
File: syscall.c

int map_check_no_btf(const struct bpf_map *map,
		     const struct btf *btf,
		     const struct btf_type *key_type,
		     const struct btf_type *value_type)
{
	return -ENOTSUPP;
}

Project: linux
File: syscall.c

bpf_prog_load_check_attach(enum bpf_prog_type prog_type,
			   enum bpf_attach_type expected_attach_type,
			   struct btf *attach_btf, u32 btf_id,
			   struct bpf_prog *dst_prog)
{
	if (btf_id) {
		if (btf_id > BTF_MAX_TYPE)
			return -EINVAL;

		if (!attach_btf && !dst_prog)
			return -EINVAL;

		switch (prog_type) {
		case BPF_PROG_TYPE_TRACING:
		case BPF_PROG_TYPE_LSM:
		case BPF_PROG_TYPE_STRUCT_OPS:
		case BPF_PROG_TYPE_EXT:
			break;
		default:
			return -EINVAL;
		}
	}

	if (attach_btf && (!btf_id || dst_prog))
		return -EINVAL;

	if (dst_prog && prog_type != BPF_PROG_TYPE_TRACING &&
	    prog_type != BPF_PROG_TYPE_EXT)
		return -EINVAL;

	switch (prog_type) {
	case BPF_PROG_TYPE_CGROUP_SOCK:
		switch (expected_attach_type) {
		case BPF_CGROUP_INET_SOCK_CREATE:
		case BPF_CGROUP_INET_SOCK_RELEASE:
		case BPF_CGROUP_INET4_POST_BIND:
		case BPF_CGROUP_INET6_POST_BIND:
			return 0;
		default:
			return -EINVAL;
		}
	case BPF_PROG_TYPE_CGROUP_SOCK_ADDR:
		switch (expected_attach_type) {
		case BPF_CGROUP_INET4_BIND:
		case BPF_CGROUP_INET6_BIND:
		case BPF_CGROUP_INET4_CONNECT:
		case BPF_CGROUP_INET6_CONNECT:
		case BPF_CGROUP_INET4_GETPEERNAME:
		case BPF_CGROUP_INET6_GETPEERNAME:
		case BPF_CGROUP_INET4_GETSOCKNAME:
		case BPF_CGROUP_INET6_GETSOCKNAME:
		case BPF_CGROUP_UDP4_SENDMSG:
		case BPF_CGROUP_UDP6_SENDMSG:
		case BPF_CGROUP_UDP4_RECVMSG:
		case BPF_CGROUP_UDP6_RECVMSG:
			return 0;
		default:
			return -EINVAL;
		}
	case BPF_PROG_TYPE_CGROUP_SKB:
		switch (expected_attach_type) {
		case BPF_CGROUP_INET_INGRESS:
		case BPF_CGROUP_INET_EGRESS:
			return 0;
		default:
			return -EINVAL;
		}
	case BPF_PROG_TYPE_CGROUP_SOCKOPT:
		switch (expected_attach_type) {
		case BPF_CGROUP_SETSOCKOPT:
		case BPF_CGROUP_GETSOCKOPT:
			return 0;
		default:
			return -EINVAL;
		}
	case BPF_PROG_TYPE_SK_LOOKUP:
		if (expected_attach_type == BPF_SK_LOOKUP)
			return 0;
		return -EINVAL;
	case BPF_PROG_TYPE_EXT:
		if (expected_attach_type)
			return -EINVAL;
		fallthrough;
	default:
		return 0;
	}
}

Project: linux
File: syscall.c

static int bpf_prog_attach(const union bpf_attr *attr)
{
	enum bpf_prog_type ptype;
	struct bpf_prog *prog;
	int ret;

	if (CHECK_ATTR(BPF_PROG_ATTACH))
		return -EINVAL;

	if (attr->attach_flags & ~BPF_F_ATTACH_MASK)
		return -EINVAL;

	ptype = attach_type_to_prog_type(attr->attach_type);
	if (ptype == BPF_PROG_TYPE_UNSPEC)
		return -EINVAL;

	prog = bpf_prog_get_type(attr->attach_bpf_fd, ptype);
	if (IS_ERR(prog))
		return PTR_ERR(prog);

	if (bpf_prog_attach_check_attach_type(prog, attr->attach_type)) {
		bpf_prog_put(prog);
		return -EINVAL;
	}

	switch (ptype) {
	case BPF_PROG_TYPE_SK_SKB:
	case BPF_PROG_TYPE_SK_MSG:
		ret = sock_map_get_from_fd(attr, prog);
		break;
	case BPF_PROG_TYPE_LIRC_MODE2:
		ret = lirc_prog_attach(attr, prog);
		break;
	case BPF_PROG_TYPE_FLOW_DISSECTOR:
		ret = netns_bpf_prog_attach(attr, prog);
		break;
	case BPF_PROG_TYPE_CGROUP_DEVICE:
	case BPF_PROG_TYPE_CGROUP_SKB:
	case BPF_PROG_TYPE_CGROUP_SOCK:
	case BPF_PROG_TYPE_CGROUP_SOCK_ADDR:
	case BPF_PROG_TYPE_CGROUP_SOCKOPT:
	case BPF_PROG_TYPE_CGROUP_SYSCTL:
	case BPF_PROG_TYPE_SOCK_OPS:
		ret = cgroup_bpf_prog_attach(attr, ptype, prog);
		break;
	default:
		ret = -EINVAL;
	}

	if (ret)
		bpf_prog_put(prog);
	return ret;
}

Project: linux
File: syscall.c

static int bpf_tracing_prog_attach(struct bpf_prog *prog,
				   int tgt_prog_fd,
				   u32 btf_id)
{
	struct bpf_link_primer link_primer;
	struct bpf_prog *tgt_prog = NULL;
	struct bpf_trampoline *tr = NULL;
	struct bpf_tracing_link *link;
	u64 key = 0;
	int err;

	switch (prog->type) {
	case BPF_PROG_TYPE_TRACING:
		if (prog->expected_attach_type != BPF_TRACE_FENTRY &&
		    prog->expected_attach_type != BPF_TRACE_FEXIT &&
		    prog->expected_attach_type != BPF_MODIFY_RETURN) {
			err = -EINVAL;
			goto out_put_prog;
		}
		break;
	case BPF_PROG_TYPE_EXT:
		if (prog->expected_attach_type != 0) {
			err = -EINVAL;
			goto out_put_prog;
		}
		break;
	case BPF_PROG_TYPE_LSM:
		if (prog->expected_attach_type != BPF_LSM_MAC) {
			err = -EINVAL;
			goto out_put_prog;
		}
		break;
	default:
		err = -EINVAL;
		goto out_put_prog;
	}

	if (!!tgt_prog_fd != !!btf_id) {
		err = -EINVAL;
		goto out_put_prog;
	}

	if (tgt_prog_fd) {
		/* For now we only allow new targets for BPF_PROG_TYPE_EXT */
		if (prog->type != BPF_PROG_TYPE_EXT) {
			err = -EINVAL;
			goto out_put_prog;
		}

		tgt_prog = bpf_prog_get(tgt_prog_fd);
		if (IS_ERR(tgt_prog)) {
			err = PTR_ERR(tgt_prog);
			tgt_prog = NULL;
			goto out_put_prog;
		}

		key = bpf_trampoline_compute_key(tgt_prog, NULL, btf_id);
	}

	link = kzalloc(sizeof(*link), GFP_USER);
	if (!link) {
		err = -ENOMEM;
		goto out_put_prog;
	}
	bpf_link_init(&link->link, BPF_LINK_TYPE_TRACING,
		      &bpf_tracing_link_lops, prog);
	link->attach_type = prog->expected_attach_type;

	mutex_lock(&prog->aux->dst_mutex);

	/* There are a few possible cases here:
	 *
	 * - if prog->aux->dst_trampoline is set, the program was just loaded
	 *   and not yet attached to anything, so we can use the values stored
	 *   in prog->aux
	 *
	 * - if prog->aux->dst_trampoline is NULL, the program has already been
         *   attached to a target and its initial target was cleared (below)
	 *
	 * - if tgt_prog != NULL, the caller specified tgt_prog_fd +
	 *   target_btf_id using the link_create API.
	 *
	 * - if tgt_prog == NULL when this function was called using the old
         *   raw_tracepoint_open API, and we need a target from prog->aux
         *
         * The combination of no saved target in prog->aux, and no target
         * specified on load is illegal, and we reject that here.
	 */
	if (!prog->aux->dst_trampoline && !tgt_prog) {
		err = -ENOENT;
		goto out_unlock;
	}

	if (!prog->aux->dst_trampoline ||
	    (key && key != prog->aux->dst_trampoline->key)) {
		/* If there is no saved target, or the specified target is
		 * different from the destination specified at load time, we
		 * need a new trampoline and a check for compatibility
		 */
		struct bpf_attach_target_info tgt_info = {};

		err = bpf_check_attach_target(NULL, prog, tgt_prog, btf_id,
					      &tgt_info);
		if (err)
			goto out_unlock;

		tr = bpf_trampoline_get(key, &tgt_info);
		if (!tr) {
			err = -ENOMEM;
			goto out_unlock;
		}
	} else {
		/* The caller didn't specify a target, or the target was the
		 * same as the destination supplied during program load. This
		 * means we can reuse the trampoline and reference from program
		 * load time, and there is no need to allocate a new one. This
		 * can only happen once for any program, as the saved values in
		 * prog->aux are cleared below.
		 */
		tr = prog->aux->dst_trampoline;
		tgt_prog = prog->aux->dst_prog;
	}

	err = bpf_link_prime(&link->link, &link_primer);
	if (err)
		goto out_unlock;

	err = bpf_trampoline_link_prog(prog, tr);
	if (err) {
		bpf_link_cleanup(&link_primer);
		link = NULL;
		goto out_unlock;
	}

	link->tgt_prog = tgt_prog;
	link->trampoline = tr;

	/* Always clear the trampoline and target prog from prog->aux to make
	 * sure the original attach destination is not kept alive after a
	 * program is (re-)attached to another target.
	 */
	if (prog->aux->dst_prog &&
	    (tgt_prog_fd || tr != prog->aux->dst_trampoline))
		/* got extra prog ref from syscall, or attaching to different prog */
		bpf_prog_put(prog->aux->dst_prog);
	if (prog->aux->dst_trampoline && tr != prog->aux->dst_trampoline)
		/* we allocated a new trampoline, so free the old one */
		bpf_trampoline_put(prog->aux->dst_trampoline);

	prog->aux->dst_prog = NULL;
	prog->aux->dst_trampoline = NULL;
	mutex_unlock(&prog->aux->dst_mutex);

	return bpf_link_settle(&link_primer);
out_unlock:
	if (tr && tr != prog->aux->dst_trampoline)
		bpf_trampoline_put(tr);
	mutex_unlock(&prog->aux->dst_mutex);
	kfree(link);
out_put_prog:
	if (tgt_prog_fd && tgt_prog)
		bpf_prog_put(tgt_prog);
	return err;
}

Project: linux
File: syscall.c

static void bpf_prog_load_fixup_attach_type(union bpf_attr *attr)
{
	switch (attr->prog_type) {
	case BPF_PROG_TYPE_CGROUP_SOCK:
		/* Unfortunately BPF_ATTACH_TYPE_UNSPEC enumeration doesn't
		 * exist so checking for non-zero is the way to go here.
		 */
		if (!attr->expected_attach_type)
			attr->expected_attach_type =
				BPF_CGROUP_INET_SOCK_CREATE;
		break;
	}
}

Project: linux
File: syscall.c

static void bpf_prog_get_stats(const struct bpf_prog *prog,
			       struct bpf_prog_stats *stats)
{
	u64 nsecs = 0, cnt = 0, misses = 0;
	int cpu;

	for_each_possible_cpu(cpu) {
		const struct bpf_prog_stats *st;
		unsigned int start;
		u64 tnsecs, tcnt, tmisses;

		st = per_cpu_ptr(prog->stats, cpu);
		do {
			start = u64_stats_fetch_begin_irq(&st->syncp);
			tnsecs = st->nsecs;
			tcnt = st->cnt;
			tmisses = st->misses;
		} while (u64_stats_fetch_retry_irq(&st->syncp, start));
		nsecs += tnsecs;
		cnt += tcnt;
		misses += tmisses;
	}
	stats->nsecs = nsecs;
	stats->cnt = cnt;
	stats->misses = misses;
}

Project: linux
File: syscall.c

static ssize_t bpf_dummy_write(struct file *filp, const char __user *buf,
			       size_t siz, loff_t *ppos)
{
	/* We need this handler such that alloc_file() enables
	 * f_mode with FMODE_CAN_WRITE.
	 */
	return -EINVAL;
}

Project: linux
File: syscall.c

static int bpf_link_alloc_id(struct bpf_link *link)
{
	int id;

	idr_preload(GFP_KERNEL);
	spin_lock_bh(&link_idr_lock);
	id = idr_alloc_cyclic(&link_idr, link, 1, INT_MAX, GFP_ATOMIC);
	spin_unlock_bh(&link_idr_lock);
	idr_preload_end();

	return id;
}

Project: linux
File: syscall.c

static void bpf_map_release_memcg(struct bpf_map *map)
{
}

Project: linux
File: syscall.c

static int bpf_link_release(struct inode *inode, struct file *filp)
{
	struct bpf_link *link = filp->private_data;

	bpf_link_put(link);
	return 0;
}

Project: linux
File: syscall.c

static void bpf_map_release_memcg(struct bpf_map *map)
{
	mem_cgroup_put(map->memcg);
}

Project: linux
File: syscall.c

struct bpf_map *__bpf_map_get(struct fd f)
{
	if (!f.file)
		return ERR_PTR(-EBADF);
	if (f.file->f_op != &bpf_map_fops) {
		fdput(f);
		return ERR_PTR(-EINVAL);
	}

	return f.file->private_data;
}

Project: linux
File: syscall.c

static void bpf_link_free(struct bpf_link *link)
{
	bpf_link_free_id(link->id);
	if (link->prog) {
		/* detach BPF program, clean up used resources */
		link->ops->release(link);
		bpf_prog_put(link->prog);
	}
	/* free bpf_link and its containing memory */
	link->ops->dealloc(link);
}

Project: linux
File: syscall.c

void bpf_map_free_id(struct bpf_map *map, bool do_idr_lock)
{
	unsigned long flags;

	/* Offloaded maps are removed from the IDR store when their device
	 * disappears - even if someone holds an fd to them they are unusable,
	 * the memory is gone, all ops will fail; they are simply waiting for
	 * refcnt to drop to be freed.
	 */
	if (!map->id)
		return;

	if (do_idr_lock)
		spin_lock_irqsave(&map_idr_lock, flags);
	else
		__acquire(&map_idr_lock);

	idr_remove(&map_idr, map->id);
	map->id = 0;

	if (do_idr_lock)
		spin_unlock_irqrestore(&map_idr_lock, flags);
	else
		__release(&map_idr_lock);
}

Project: linux
File: syscall.c

attach_type_to_prog_type(enum bpf_attach_type attach_type)
{
	switch (attach_type) {
	case BPF_CGROUP_INET_INGRESS:
	case BPF_CGROUP_INET_EGRESS:
		return BPF_PROG_TYPE_CGROUP_SKB;
	case BPF_CGROUP_INET_SOCK_CREATE:
	case BPF_CGROUP_INET_SOCK_RELEASE:
	case BPF_CGROUP_INET4_POST_BIND:
	case BPF_CGROUP_INET6_POST_BIND:
		return BPF_PROG_TYPE_CGROUP_SOCK;
	case BPF_CGROUP_INET4_BIND:
	case BPF_CGROUP_INET6_BIND:
	case BPF_CGROUP_INET4_CONNECT:
	case BPF_CGROUP_INET6_CONNECT:
	case BPF_CGROUP_INET4_GETPEERNAME:
	case BPF_CGROUP_INET6_GETPEERNAME:
	case BPF_CGROUP_INET4_GETSOCKNAME:
	case BPF_CGROUP_INET6_GETSOCKNAME:
	case BPF_CGROUP_UDP4_SENDMSG:
	case BPF_CGROUP_UDP6_SENDMSG:
	case BPF_CGROUP_UDP4_RECVMSG:
	case BPF_CGROUP_UDP6_RECVMSG:
		return BPF_PROG_TYPE_CGROUP_SOCK_ADDR;
	case BPF_CGROUP_SOCK_OPS:
		return BPF_PROG_TYPE_SOCK_OPS;
	case BPF_CGROUP_DEVICE:
		return BPF_PROG_TYPE_CGROUP_DEVICE;
	case BPF_SK_MSG_VERDICT:
		return BPF_PROG_TYPE_SK_MSG;
	case BPF_SK_SKB_STREAM_PARSER:
	case BPF_SK_SKB_STREAM_VERDICT:
		return BPF_PROG_TYPE_SK_SKB;
	case BPF_LIRC_MODE2:
		return BPF_PROG_TYPE_LIRC_MODE2;
	case BPF_FLOW_DISSECTOR:
		return BPF_PROG_TYPE_FLOW_DISSECTOR;
	case BPF_CGROUP_SYSCTL:
		return BPF_PROG_TYPE_CGROUP_SYSCTL;
	case BPF_CGROUP_GETSOCKOPT:
	case BPF_CGROUP_SETSOCKOPT:
		return BPF_PROG_TYPE_CGROUP_SOCKOPT;
	case BPF_TRACE_ITER:
		return BPF_PROG_TYPE_TRACING;
	case BPF_SK_LOOKUP:
		return BPF_PROG_TYPE_SK_LOOKUP;
	case BPF_XDP:
		return BPF_PROG_TYPE_XDP;
	default:
		return BPF_PROG_TYPE_UNSPEC;
	}
}

Project: linux
File: syscall.c

static bool is_net_admin_prog_type(enum bpf_prog_type prog_type)
{
	switch (prog_type) {
	case BPF_PROG_TYPE_SCHED_CLS:
	case BPF_PROG_TYPE_SCHED_ACT:
	case BPF_PROG_TYPE_XDP:
	case BPF_PROG_TYPE_LWT_IN:
	case BPF_PROG_TYPE_LWT_OUT:
	case BPF_PROG_TYPE_LWT_XMIT:
	case BPF_PROG_TYPE_LWT_SEG6LOCAL:
	case BPF_PROG_TYPE_SK_SKB:
	case BPF_PROG_TYPE_SK_MSG:
	case BPF_PROG_TYPE_LIRC_MODE2:
	case BPF_PROG_TYPE_FLOW_DISSECTOR:
	case BPF_PROG_TYPE_CGROUP_DEVICE:
	case BPF_PROG_TYPE_CGROUP_SOCK:
	case BPF_PROG_TYPE_CGROUP_SOCK_ADDR:
	case BPF_PROG_TYPE_CGROUP_SOCKOPT:
	case BPF_PROG_TYPE_CGROUP_SYSCTL:
	case BPF_PROG_TYPE_SOCK_OPS:
	case BPF_PROG_TYPE_EXT: /* extends any prog */
		return true;
	case BPF_PROG_TYPE_CGROUP_SKB:
		/* always unpriv */
	case BPF_PROG_TYPE_SK_REUSEPORT:
		/* equivalent to SOCKET_FILTER. need CAP_BPF only */
	default:
		return false;
	}
}

Project: linux
File: verifier.c

static int check_mem_access(struct bpf_verifier_env *env, int insn_idx, u32 regno,
			    int off, int bpf_size, enum bpf_access_type t,
			    int value_regno, bool strict_alignment_once)
{
	struct bpf_reg_state *regs = cur_regs(env);
	struct bpf_reg_state *reg = regs + regno;
	struct bpf_func_state *state;
	int size, err = 0;

	size = bpf_size_to_bytes(bpf_size);
	if (size < 0)
		return size;

	/* alignment checks will add in reg->off themselves */
	err = check_ptr_alignment(env, reg, off, size, strict_alignment_once);
	if (err)
		return err;

	/* for access checks, reg->off is just part of off */
	off += reg->off;

	if (reg->type == PTR_TO_MAP_VALUE) {
		if (t == BPF_WRITE && value_regno >= 0 &&
		    is_pointer_value(env, value_regno)) {
			verbose(env, "R%d leaks addr into map\n", value_regno);
			return -EACCES;
		}
		err = check_map_access_type(env, regno, off, size, t);
		if (err)
			return err;
		err = check_map_access(env, regno, off, size, false);
		if (!err && t == BPF_READ && value_regno >= 0) {
			struct bpf_map *map = reg->map_ptr;

			/* if map is read-only, track its contents as scalars */
			if (tnum_is_const(reg->var_off) &&
			    bpf_map_is_rdonly(map) &&
			    map->ops->map_direct_value_addr) {
				int map_off = off + reg->var_off.value;
				u64 val = 0;

				err = bpf_map_direct_read(map, map_off, size,
							  &val);
				if (err)
					return err;

				regs[value_regno].type = SCALAR_VALUE;
				__mark_reg_known(&regs[value_regno], val);
			} else {
				mark_reg_unknown(env, regs, value_regno);
			}
		}
	} else if (reg->type == PTR_TO_MEM) {
		if (t == BPF_WRITE && value_regno >= 0 &&
		    is_pointer_value(env, value_regno)) {
			verbose(env, "R%d leaks addr into mem\n", value_regno);
			return -EACCES;
		}
		err = check_mem_region_access(env, regno, off, size,
					      reg->mem_size, false);
		if (!err && t == BPF_READ && value_regno >= 0)
			mark_reg_unknown(env, regs, value_regno);
	} else if (reg->type == PTR_TO_CTX) {
		enum bpf_reg_type reg_type = SCALAR_VALUE;
		struct btf *btf = NULL;
		u32 btf_id = 0;

		if (t == BPF_WRITE && value_regno >= 0 &&
		    is_pointer_value(env, value_regno)) {
			verbose(env, "R%d leaks addr into ctx\n", value_regno);
			return -EACCES;
		}

		err = check_ctx_reg(env, reg, regno);
		if (err < 0)
			return err;

		err = check_ctx_access(env, insn_idx, off, size, t, &reg_type, &btf, &btf_id);
		if (err)
			verbose_linfo(env, insn_idx, "; ");
		if (!err && t == BPF_READ && value_regno >= 0) {
			/* ctx access returns either a scalar, or a
			 * PTR_TO_PACKET[_META,_END]. In the latter
			 * case, we know the offset is zero.
			 */
			if (reg_type == SCALAR_VALUE) {
				mark_reg_unknown(env, regs, value_regno);
			} else {
				mark_reg_known_zero(env, regs,
						    value_regno);
				if (reg_type_may_be_null(reg_type))
					regs[value_regno].id = ++env->id_gen;
				/* A load of ctx field could have different
				 * actual load size with the one encoded in the
				 * insn. When the dst is PTR, it is for sure not
				 * a sub-register.
				 */
				regs[value_regno].subreg_def = DEF_NOT_SUBREG;
				if (reg_type == PTR_TO_BTF_ID ||
				    reg_type == PTR_TO_BTF_ID_OR_NULL) {
					regs[value_regno].btf = btf;
					regs[value_regno].btf_id = btf_id;
				}
			}
			regs[value_regno].type = reg_type;
		}

	} else if (reg->type == PTR_TO_STACK) {
		/* Basic bounds checks. */
		err = check_stack_access_within_bounds(env, regno, off, size, ACCESS_DIRECT, t);
		if (err)
			return err;

		state = func(env, reg);
		err = update_stack_depth(env, state, off);
		if (err)
			return err;

		if (t == BPF_READ)
			err = check_stack_read(env, regno, off, size,
					       value_regno);
		else
			err = check_stack_write(env, regno, off, size,
						value_regno, insn_idx);
	} else if (reg_is_pkt_pointer(reg)) {
		if (t == BPF_WRITE && !may_access_direct_pkt_data(env, NULL, t)) {
			verbose(env, "cannot write into packet\n");
			return -EACCES;
		}
		if (t == BPF_WRITE && value_regno >= 0 &&
		    is_pointer_value(env, value_regno)) {
			verbose(env, "R%d leaks addr into packet\n",
				value_regno);
			return -EACCES;
		}
		err = check_packet_access(env, regno, off, size, false);
		if (!err && t == BPF_READ && value_regno >= 0)
			mark_reg_unknown(env, regs, value_regno);
	} else if (reg->type == PTR_TO_FLOW_KEYS) {
		if (t == BPF_WRITE && value_regno >= 0 &&
		    is_pointer_value(env, value_regno)) {
			verbose(env, "R%d leaks addr into flow keys\n",
				value_regno);
			return -EACCES;
		}

		err = check_flow_keys_access(env, off, size);
		if (!err && t == BPF_READ && value_regno >= 0)
			mark_reg_unknown(env, regs, value_regno);
	} else if (type_is_sk_pointer(reg->type)) {
		if (t == BPF_WRITE) {
			verbose(env, "R%d cannot write into %s\n",
				regno, reg_type_str[reg->type]);
			return -EACCES;
		}
		err = check_sock_access(env, insn_idx, regno, off, size, t);
		if (!err && value_regno >= 0)
			mark_reg_unknown(env, regs, value_regno);
	} else if (reg->type == PTR_TO_TP_BUFFER) {
		err = check_tp_buffer_access(env, reg, regno, off, size);
		if (!err && t == BPF_READ && value_regno >= 0)
			mark_reg_unknown(env, regs, value_regno);
	} else if (reg->type == PTR_TO_BTF_ID) {
		err = check_ptr_to_btf_access(env, regs, regno, off, size, t,
					      value_regno);
	} else if (reg->type == CONST_PTR_TO_MAP) {
		err = check_ptr_to_map_access(env, regs, regno, off, size, t,
					      value_regno);
	} else if (reg->type == PTR_TO_RDONLY_BUF) {
		if (t == BPF_WRITE) {
			verbose(env, "R%d cannot write into %s\n",
				regno, reg_type_str[reg->type]);
			return -EACCES;
		}
		err = check_buffer_access(env, reg, regno, off, size, false,
					  "rdonly",
					  &env->prog->aux->max_rdonly_access);
		if (!err && value_regno >= 0)
			mark_reg_unknown(env, regs, value_regno);
	} else if (reg->type == PTR_TO_RDWR_BUF) {
		err = check_buffer_access(env, reg, regno, off, size, false,
					  "rdwr",
					  &env->prog->aux->max_rdwr_access);
		if (!err && t == BPF_READ && value_regno >= 0)
			mark_reg_unknown(env, regs, value_regno);
	} else {
		verbose(env, "R%d invalid mem access '%s'\n", regno,
			reg_type_str[reg->type]);
		return -EACCES;
	}

	if (!err && size < BPF_REG_SIZE && value_regno >= 0 && t == BPF_READ &&
	    regs[value_regno].type == SCALAR_VALUE) {
		/* b/h/w load zero-extends, mark upper bits as known 0 */
		coerce_reg_to_size(&regs[value_regno], size);
	}
	return err;
}

Project: linux
File: syscall.c

static u32 bpf_map_flags_retain_permanent(u32 flags)
{
	/* Some map creation flags are not tied to the map object but
	 * rather to the map fd instead, so they have no meaning upon
	 * map object inspection since multiple file descriptors with
	 * different (access) properties can exist here. Thus, given
	 * this has zero meaning for the map itself, lets clear these
	 * from here.
	 */
	return flags & ~(BPF_F_RDONLY | BPF_F_WRONLY);
}

Project: linux
File: syscall.c

static void bpf_tracing_link_show_fdinfo(const struct bpf_link *link,
					 struct seq_file *seq)
{
	struct bpf_tracing_link *tr_link =
		container_of(link, struct bpf_tracing_link, link);

	seq_printf(seq,
		   "attach_type:\t%d\n",
		   tr_link->attach_type);
}

Project: linux
File: syscall.c

int generic_map_lookup_batch(struct bpf_map *map,
				    const union bpf_attr *attr,
				    union bpf_attr __user *uattr)
{
	void __user *uobatch = u64_to_user_ptr(attr->batch.out_batch);
	void __user *ubatch = u64_to_user_ptr(attr->batch.in_batch);
	void __user *values = u64_to_user_ptr(attr->batch.values);
	void __user *keys = u64_to_user_ptr(attr->batch.keys);
	void *buf, *buf_prevkey, *prev_key, *key, *value;
	int err, retry = MAP_LOOKUP_RETRIES;
	u32 value_size, cp, max_count;

	if (attr->batch.elem_flags & ~BPF_F_LOCK)
		return -EINVAL;

	if ((attr->batch.elem_flags & BPF_F_LOCK) &&
	    !map_value_has_spin_lock(map))
		return -EINVAL;

	value_size = bpf_map_value_size(map);

	max_count = attr->batch.count;
	if (!max_count)
		return 0;

	if (put_user(0, &uattr->batch.count))
		return -EFAULT;

	buf_prevkey = kmalloc(map->key_size, GFP_USER | __GFP_NOWARN);
	if (!buf_prevkey)
		return -ENOMEM;

	buf = kmalloc(map->key_size + value_size, GFP_USER | __GFP_NOWARN);
	if (!buf) {
		kfree(buf_prevkey);
		return -ENOMEM;
	}

	err = -EFAULT;
	prev_key = NULL;
	if (ubatch && copy_from_user(buf_prevkey, ubatch, map->key_size))
		goto free_buf;
	key = buf;
	value = key + map->key_size;
	if (ubatch)
		prev_key = buf_prevkey;

	for (cp = 0; cp < max_count;) {
		rcu_read_lock();
		err = map->ops->map_get_next_key(map, prev_key, key);
		rcu_read_unlock();
		if (err)
			break;
		err = bpf_map_copy_value(map, key, value,
					 attr->batch.elem_flags);

		if (err == -ENOENT) {
			if (retry) {
				retry--;
				continue;
			}
			err = -EINTR;
			break;
		}

		if (err)
			goto free_buf;

		if (copy_to_user(keys + cp * map->key_size, key,
				 map->key_size)) {
			err = -EFAULT;
			goto free_buf;
		}
		if (copy_to_user(values + cp * value_size, value, value_size)) {
			err = -EFAULT;
			goto free_buf;
		}

		if (!prev_key)
			prev_key = buf_prevkey;

		swap(prev_key, key);
		retry = MAP_LOOKUP_RETRIES;
		cp++;
	}

	if (err == -EFAULT)
		goto free_buf;

	if ((copy_to_user(&uattr->batch.count, &cp, sizeof(cp)) ||
		    (cp && copy_to_user(uobatch, prev_key, map->key_size))))
		err = -EFAULT;

free_buf:
	kfree(buf_prevkey);
	kfree(buf);
	return err;
}

Project: linux
File: syscall.c

void *bpf_map_area_mmapable_alloc(u64 size, int numa_node)
{
	return __bpf_map_area_alloc(size, numa_node, true);
}

Project: linux
File: syscall.c

static int bpf_prog_attach_check_attach_type(const struct bpf_prog *prog,
					     enum bpf_attach_type attach_type)
{
	switch (prog->type) {
	case BPF_PROG_TYPE_CGROUP_SOCK:
	case BPF_PROG_TYPE_CGROUP_SOCK_ADDR:
	case BPF_PROG_TYPE_CGROUP_SOCKOPT:
	case BPF_PROG_TYPE_SK_LOOKUP:
		return attach_type == prog->expected_attach_type ? 0 : -EINVAL;
	case BPF_PROG_TYPE_CGROUP_SKB:
		if (!capable(CAP_NET_ADMIN))
			/* cg-skb progs can be loaded by unpriv user.
			 * check permissions at attach time.
			 */
			return -EPERM;
		return prog->enforce_expected_attach_type &&
			prog->expected_attach_type != attach_type ?
			-EINVAL : 0;
	default:
		return 0;
	}
}

Project: linux
File: syscall.c

static int map_check_btf(struct bpf_map *map, const struct btf *btf,
			 u32 btf_key_id, u32 btf_value_id)
{
	const struct btf_type *key_type, *value_type;
	u32 key_size, value_size;
	int ret = 0;

	/* Some maps allow key to be unspecified. */
	if (btf_key_id) {
		key_type = btf_type_id_size(btf, &btf_key_id, &key_size);
		if (!key_type || key_size != map->key_size)
			return -EINVAL;
	} else {
		key_type = btf_type_by_id(btf, 0);
		if (!map->ops->map_check_btf)
			return -EINVAL;
	}

	value_type = btf_type_id_size(btf, &btf_value_id, &value_size);
	if (!value_type || value_size != map->value_size)
		return -EINVAL;

	map->spin_lock_off = btf_find_spin_lock(btf, value_type);

	if (map_value_has_spin_lock(map)) {
		if (map->map_flags & BPF_F_RDONLY_PROG)
			return -EACCES;
		if (map->map_type != BPF_MAP_TYPE_HASH &&
		    map->map_type != BPF_MAP_TYPE_ARRAY &&
		    map->map_type != BPF_MAP_TYPE_CGROUP_STORAGE &&
		    map->map_type != BPF_MAP_TYPE_SK_STORAGE &&
		    map->map_type != BPF_MAP_TYPE_INODE_STORAGE &&
		    map->map_type != BPF_MAP_TYPE_TASK_STORAGE)
			return -ENOTSUPP;
		if (map->spin_lock_off + sizeof(struct bpf_spin_lock) >
		    map->value_size) {
			WARN_ONCE(1,
				  "verifier bug spin_lock_off %d value_size %d\n",
				  map->spin_lock_off, map->value_size);
			return -EFAULT;
		}
	}

	if (map->ops->map_check_btf)
		ret = map->ops->map_check_btf(map, btf, key_type, value_type);

	return ret;
}

Project: linux
File: syscall.c

static void bpf_audit_prog(const struct bpf_prog *prog, unsigned int op)
{
	struct audit_context *ctx = NULL;
	struct audit_buffer *ab;

	if (WARN_ON_ONCE(op >= BPF_AUDIT_MAX))
		return;
	if (audit_enabled == AUDIT_OFF)
		return;
	if (op == BPF_AUDIT_LOAD)
		ctx = audit_context();
	ab = audit_log_start(ctx, GFP_ATOMIC, AUDIT_BPF);
	if (unlikely(!ab))
		return;
	audit_log_format(ab, "prog-id=%u op=%s",
			 prog->aux->id, bpf_audit_str[op]);
	audit_log_end(ab);
}

Project: linux
File: syscall.c

static int link_update(union bpf_attr *attr)
{
	struct bpf_prog *old_prog = NULL, *new_prog;
	struct bpf_link *link;
	u32 flags;
	int ret;

	if (CHECK_ATTR(BPF_LINK_UPDATE))
		return -EINVAL;

	flags = attr->link_update.flags;
	if (flags & ~BPF_F_REPLACE)
		return -EINVAL;

	link = bpf_link_get_from_fd(attr->link_update.link_fd);
	if (IS_ERR(link))
		return PTR_ERR(link);

	new_prog = bpf_prog_get(attr->link_update.new_prog_fd);
	if (IS_ERR(new_prog)) {
		ret = PTR_ERR(new_prog);
		goto out_put_link;
	}

	if (flags & BPF_F_REPLACE) {
		old_prog = bpf_prog_get(attr->link_update.old_prog_fd);
		if (IS_ERR(old_prog)) {
			ret = PTR_ERR(old_prog);
			old_prog = NULL;
			goto out_put_progs;
		}
	} else if (attr->link_update.old_prog_fd) {
		ret = -EINVAL;
		goto out_put_progs;
	}

	if (link->ops->update_prog)
		ret = link->ops->update_prog(link, new_prog, old_prog);
	else
		ret = -EINVAL;

out_put_progs:
	if (old_prog)
		bpf_prog_put(old_prog);
	if (ret)
		bpf_prog_put(new_prog);
out_put_link:
	bpf_link_put(link);
	return ret;
}

Project: linux
File: verifier.c

static int check_return_code(struct bpf_verifier_env *env)
{
	struct tnum enforce_attach_type_range = tnum_unknown;
	const struct bpf_prog *prog = env->prog;
	struct bpf_reg_state *reg;
	struct tnum range = tnum_range(0, 1);
	enum bpf_prog_type prog_type = resolve_prog_type(env->prog);
	int err;
	const bool is_subprog = env->cur_state->frame[0]->subprogno;

	/* LSM and struct_ops func-ptr's return type could be "void" */
	if (!is_subprog &&
	    (prog_type == BPF_PROG_TYPE_STRUCT_OPS ||
	     prog_type == BPF_PROG_TYPE_LSM) &&
	    !prog->aux->attach_func_proto->type)
		return 0;

	/* eBPF calling convetion is such that R0 is used
	 * to return the value from eBPF program.
	 * Make sure that it's readable at this time
	 * of bpf_exit, which means that program wrote
	 * something into it earlier
	 */
	err = check_reg_arg(env, BPF_REG_0, SRC_OP);
	if (err)
		return err;

	if (is_pointer_value(env, BPF_REG_0)) {
		verbose(env, "R0 leaks addr as return value\n");
		return -EACCES;
	}

	reg = cur_regs(env) + BPF_REG_0;
	if (is_subprog) {
		if (reg->type != SCALAR_VALUE) {
			verbose(env, "At subprogram exit the register R0 is not a scalar value (%s)\n",
				reg_type_str[reg->type]);
			return -EINVAL;
		}
		return 0;
	}

	switch (prog_type) {
	case BPF_PROG_TYPE_CGROUP_SOCK_ADDR:
		if (env->prog->expected_attach_type == BPF_CGROUP_UDP4_RECVMSG ||
		    env->prog->expected_attach_type == BPF_CGROUP_UDP6_RECVMSG ||
		    env->prog->expected_attach_type == BPF_CGROUP_INET4_GETPEERNAME ||
		    env->prog->expected_attach_type == BPF_CGROUP_INET6_GETPEERNAME ||
		    env->prog->expected_attach_type == BPF_CGROUP_INET4_GETSOCKNAME ||
		    env->prog->expected_attach_type == BPF_CGROUP_INET6_GETSOCKNAME)
			range = tnum_range(1, 1);
		if (env->prog->expected_attach_type == BPF_CGROUP_INET4_BIND ||
		    env->prog->expected_attach_type == BPF_CGROUP_INET6_BIND)
			range = tnum_range(0, 3);
		break;
	case BPF_PROG_TYPE_CGROUP_SKB:
		if (env->prog->expected_attach_type == BPF_CGROUP_INET_EGRESS) {
			range = tnum_range(0, 3);
			enforce_attach_type_range = tnum_range(2, 3);
		}
		break;
	case BPF_PROG_TYPE_CGROUP_SOCK:
	case BPF_PROG_TYPE_SOCK_OPS:
	case BPF_PROG_TYPE_CGROUP_DEVICE:
	case BPF_PROG_TYPE_CGROUP_SYSCTL:
	case BPF_PROG_TYPE_CGROUP_SOCKOPT:
		break;
	case BPF_PROG_TYPE_RAW_TRACEPOINT:
		if (!env->prog->aux->attach_btf_id)
			return 0;
		range = tnum_const(0);
		break;
	case BPF_PROG_TYPE_TRACING:
		switch (env->prog->expected_attach_type) {
		case BPF_TRACE_FENTRY:
		case BPF_TRACE_FEXIT:
			range = tnum_const(0);
			break;
		case BPF_TRACE_RAW_TP:
		case BPF_MODIFY_RETURN:
			return 0;
		case BPF_TRACE_ITER:
			break;
		default:
			return -ENOTSUPP;
		}
		break;
	case BPF_PROG_TYPE_SK_LOOKUP:
		range = tnum_range(SK_DROP, SK_PASS);
		break;
	case BPF_PROG_TYPE_EXT:
		/* freplace program can return anything as its return value
		 * depends on the to-be-replaced kernel func or bpf program.
		 */
	default:
		return 0;
	}

	if (reg->type != SCALAR_VALUE) {
		verbose(env, "At program exit the register R0 is not a known value (%s)\n",
			reg_type_str[reg->type]);
		return -EINVAL;
	}

	if (!tnum_in(range, reg->var_off)) {
		char tn_buf[48];

		verbose(env, "At program exit the register R0 ");
		if (!tnum_is_unknown(reg->var_off)) {
			tnum_strn(tn_buf, sizeof(tn_buf), reg->var_off);
			verbose(env, "has value %s", tn_buf);
		} else {
			verbose(env, "has unknown scalar value");
		}
		tnum_strn(tn_buf, sizeof(tn_buf), range);
		verbose(env, " should have been in %s\n", tn_buf);
		return -EINVAL;
	}

	if (!tnum_is_unknown(enforce_attach_type_range) &&
	    tnum_in(enforce_attach_type_range, reg->var_off))
		env->prog->enforce_expected_attach_type = 1;
	return 0;
}

Project: linux
File: syscall.c

struct bpf_map *bpf_map_get_with_uref(u32 ufd)
{
	struct fd f = fdget(ufd);
	struct bpf_map *map;

	map = __bpf_map_get(f);
	if (IS_ERR(map))
		return map;

	bpf_map_inc_with_uref(map);
	fdput(f);

	return map;
}

Project: linux
File: syscall.c

int bpf_prog_new_fd(struct bpf_prog *prog)
{
	int ret;

	ret = security_bpf_prog(prog);
	if (ret < 0)
		return ret;

	return anon_inode_getfd("bpf-prog", &bpf_prog_fops, prog,
				O_RDWR | O_CLOEXEC);
}

Project: linux
File: syscall.c

void bpf_map_inc_with_uref(struct bpf_map *map)
{
	atomic64_inc(&map->refcnt);
	atomic64_inc(&map->usercnt);
}

Project: linux
File: syscall.c

static int bpf_prog_release(struct inode *inode, struct file *filp)
{
	struct bpf_prog *prog = filp->private_data;

	bpf_prog_put(prog);
	return 0;
}

Project: linux
File: syscall.c

bool bpf_prog_get_ok(struct bpf_prog *prog,
			    enum bpf_prog_type *attach_type, bool attach_drv)
{
	/* not an attachment, just a refcount inc, always allow */
	if (!attach_type)
		return true;

	if (prog->type != *attach_type)
		return false;
	if (bpf_prog_is_dev_bound(prog->aux) && !attach_drv)
		return false;

	return true;
}

Project: linux
File: syscall.c

static int map_lookup_elem(union bpf_attr *attr)
{
	void __user *ukey = u64_to_user_ptr(attr->key);
	void __user *uvalue = u64_to_user_ptr(attr->value);
	int ufd = attr->map_fd;
	struct bpf_map *map;
	void *key, *value;
	u32 value_size;
	struct fd f;
	int err;

	if (CHECK_ATTR(BPF_MAP_LOOKUP_ELEM))
		return -EINVAL;

	if (attr->flags & ~BPF_F_LOCK)
		return -EINVAL;

	f = fdget(ufd);
	map = __bpf_map_get(f);
	if (IS_ERR(map))
		return PTR_ERR(map);
	if (!(map_get_sys_perms(map, f) & FMODE_CAN_READ)) {
		err = -EPERM;
		goto err_put;
	}

	if ((attr->flags & BPF_F_LOCK) &&
	    !map_value_has_spin_lock(map)) {
		err = -EINVAL;
		goto err_put;
	}

	key = __bpf_copy_key(ukey, map->key_size);
	if (IS_ERR(key)) {
		err = PTR_ERR(key);
		goto err_put;
	}

	value_size = bpf_map_value_size(map);

	err = -ENOMEM;
	value = kmalloc(value_size, GFP_USER | __GFP_NOWARN);
	if (!value)
		goto free_key;

	err = bpf_map_copy_value(map, key, value, attr->flags);
	if (err)
		goto free_value;

	err = -EFAULT;
	if (copy_to_user(uvalue, value, value_size) != 0)
		goto free_value;

	err = 0;

free_value:
	kfree(value);
free_key:
	kfree(key);
err_put:
	fdput(f);
	return err;
}

Project: linux
File: syscall.c

static int map_get_next_key(union bpf_attr *attr)
{
	void __user *ukey = u64_to_user_ptr(attr->key);
	void __user *unext_key = u64_to_user_ptr(attr->next_key);
	int ufd = attr->map_fd;
	struct bpf_map *map;
	void *key, *next_key;
	struct fd f;
	int err;

	if (CHECK_ATTR(BPF_MAP_GET_NEXT_KEY))
		return -EINVAL;

	f = fdget(ufd);
	map = __bpf_map_get(f);
	if (IS_ERR(map))
		return PTR_ERR(map);
	if (!(map_get_sys_perms(map, f) & FMODE_CAN_READ)) {
		err = -EPERM;
		goto err_put;
	}

	if (ukey) {
		key = __bpf_copy_key(ukey, map->key_size);
		if (IS_ERR(key)) {
			err = PTR_ERR(key);
			goto err_put;
		}
	} else {
		key = NULL;
	}

	err = -ENOMEM;
	next_key = kmalloc(map->key_size, GFP_USER);
	if (!next_key)
		goto free_key;

	if (bpf_map_is_dev_bound(map)) {
		err = bpf_map_offload_get_next_key(map, key, next_key);
		goto out;
	}

	rcu_read_lock();
	err = map->ops->map_get_next_key(map, key, next_key);
	rcu_read_unlock();
out:
	if (err)
		goto free_next_key;

	err = -EFAULT;
	if (copy_to_user(unext_key, next_key, map->key_size) != 0)
		goto free_next_key;

	err = 0;

free_next_key:
	kfree(next_key);
free_key:
	kfree(key);
err_put:
	fdput(f);
	return err;
}

Project: linux
File: syscall.c

static int bpf_prog_detach(const union bpf_attr *attr)
{
	enum bpf_prog_type ptype;

	if (CHECK_ATTR(BPF_PROG_DETACH))
		return -EINVAL;

	ptype = attach_type_to_prog_type(attr->attach_type);

	switch (ptype) {
	case BPF_PROG_TYPE_SK_MSG:
	case BPF_PROG_TYPE_SK_SKB:
		return sock_map_prog_detach(attr, ptype);
	case BPF_PROG_TYPE_LIRC_MODE2:
		return lirc_prog_detach(attr);
	case BPF_PROG_TYPE_FLOW_DISSECTOR:
		return netns_bpf_prog_detach(attr, ptype);
	case BPF_PROG_TYPE_CGROUP_DEVICE:
	case BPF_PROG_TYPE_CGROUP_SKB:
	case BPF_PROG_TYPE_CGROUP_SOCK:
	case BPF_PROG_TYPE_CGROUP_SOCK_ADDR:
	case BPF_PROG_TYPE_CGROUP_SOCKOPT:
	case BPF_PROG_TYPE_CGROUP_SYSCTL:
	case BPF_PROG_TYPE_SOCK_OPS:
		return cgroup_bpf_prog_detach(attr, ptype);
	default:
		return -EINVAL;
	}
}

Project: linux
File: syscall.c

void *bpf_map_kmalloc_node(const struct bpf_map *map, size_t size, gfp_t flags,
			   int node)
{
	struct mem_cgroup *old_memcg;
	void *ptr;

	old_memcg = set_active_memcg(map->memcg);
	ptr = kmalloc_node(size, flags | __GFP_ACCOUNT, node);
	set_active_memcg(old_memcg);

	return ptr;
}

Project: linux
File: syscall.c

int bpf_obj_name_cpy(char *dst, const char *src, unsigned int size)
{
	const char *end = src + size;
	const char *orig_src = src;

	memset(dst, 0, size);
	/* Copy all isalnum(), '_' and '.' chars. */
	while (src < end && *src) {
		if (!isalnum(*src) &&
		    *src != '_' && *src != '.')
			return -EINVAL;
		*dst++ = *src++;
	}

	/* No '\0' found in "size" number of bytes */
	if (src == end)
		return -EINVAL;

	return src - orig_src;
}

Project: linux
File: syscall.c

int bpf_link_new_fd(struct bpf_link *link)
{
	return anon_inode_getfd("bpf-link", &bpf_link_fops, link, O_CLOEXEC);
}

Project: linux
File: syscall.c

static void bpf_tracing_link_dealloc(struct bpf_link *link)
{
	struct bpf_tracing_link *tr_link =
		container_of(link, struct bpf_tracing_link, link);

	kfree(tr_link);
}

Project: linux
File: syscall.c

struct bpf_prog *bpf_prog_get_curr_or_next(u32 *id)
{
	struct bpf_prog *prog;

	spin_lock_bh(&prog_idr_lock);
again:
	prog = idr_get_next(&prog_idr, id);
	if (prog) {
		prog = bpf_prog_inc_not_zero(prog);
		if (IS_ERR(prog)) {
			(*id)++;
			goto again;
		}
	}
	spin_unlock_bh(&prog_idr_lock);

	return prog;
}

Project: linux
File: syscall.c

static int bpf_enable_runtime_stats(void)
{
	int fd;

	mutex_lock(&bpf_stats_enabled_mutex);

	/* Set a very high limit to avoid overflow */
	if (static_key_count(&bpf_stats_enabled_key.key) > INT_MAX / 2) {
		mutex_unlock(&bpf_stats_enabled_mutex);
		return -EBUSY;
	}

	fd = anon_inode_getfd("bpf-stats", &bpf_stats_fops, NULL, O_CLOEXEC);
	if (fd >= 0)
		static_key_slow_inc(&bpf_stats_enabled_key.key);

	mutex_unlock(&bpf_stats_enabled_mutex);
	return fd;
}

Project: linux
File: syscall.c

int bpf_get_file_flag(int flags)
{
	if ((flags & BPF_F_RDONLY) && (flags & BPF_F_WRONLY))
		return -EINVAL;
	if (flags & BPF_F_RDONLY)
		return O_RDONLY;
	if (flags & BPF_F_WRONLY)
		return O_WRONLY;
	return O_RDWR;
}

Project: linux
File: syscall.c

static struct bpf_map *find_and_alloc_map(union bpf_attr *attr)
{
	const struct bpf_map_ops *ops;
	u32 type = attr->map_type;
	struct bpf_map *map;
	int err;

	if (type >= ARRAY_SIZE(bpf_map_types))
		return ERR_PTR(-EINVAL);
	type = array_index_nospec(type, ARRAY_SIZE(bpf_map_types));
	ops = bpf_map_types[type];
	if (!ops)
		return ERR_PTR(-EINVAL);

	if (ops->map_alloc_check) {
		err = ops->map_alloc_check(attr);
		if (err)
			return ERR_PTR(err);
	}
	if (attr->map_ifindex)
		ops = &bpf_map_offload_ops;
	map = ops->map_alloc(attr);
	if (IS_ERR(map))
		return map;
	map->ops = ops;
	map->map_type = type;
	return map;
}

Project: linux
File: verifier.c

static int do_check_common(struct bpf_verifier_env *env, int subprog)
{
	bool pop_log = !(env->log.level & BPF_LOG_LEVEL2);
	struct bpf_verifier_state *state;
	struct bpf_reg_state *regs;
	int ret, i;

	env->prev_linfo = NULL;
	env->pass_cnt++;

	state = kzalloc(sizeof(struct bpf_verifier_state), GFP_KERNEL);
	if (!state)
		return -ENOMEM;
	state->curframe = 0;
	state->speculative = false;
	state->branches = 1;
	state->frame[0] = kzalloc(sizeof(struct bpf_func_state), GFP_KERNEL);
	if (!state->frame[0]) {
		kfree(state);
		return -ENOMEM;
	}
	env->cur_state = state;
	init_func_state(env, state->frame[0],
			BPF_MAIN_FUNC /* callsite */,
			0 /* frameno */,
			subprog);

	regs = state->frame[state->curframe]->regs;
	if (subprog || env->prog->type == BPF_PROG_TYPE_EXT) {
		ret = btf_prepare_func_args(env, subprog, regs);
		if (ret)
			goto out;
		for (i = BPF_REG_1; i <= BPF_REG_5; i++) {
			if (regs[i].type == PTR_TO_CTX)
				mark_reg_known_zero(env, regs, i);
			else if (regs[i].type == SCALAR_VALUE)
				mark_reg_unknown(env, regs, i);
			else if (regs[i].type == PTR_TO_MEM_OR_NULL) {
				const u32 mem_size = regs[i].mem_size;

				mark_reg_known_zero(env, regs, i);
				regs[i].mem_size = mem_size;
				regs[i].id = ++env->id_gen;
			}
		}
	} else {
		/* 1st arg to a function */
		regs[BPF_REG_1].type = PTR_TO_CTX;
		mark_reg_known_zero(env, regs, BPF_REG_1);
		ret = btf_check_func_arg_match(env, subprog, regs);
		if (ret == -EFAULT)
			/* unlikely verifier bug. abort.
			 * ret == 0 and ret < 0 are sadly acceptable for
			 * main() function due to backward compatibility.
			 * Like socket filter program may be written as:
			 * int bpf_prog(struct pt_regs *ctx)
			 * and never dereference that ctx in the program.
			 * 'struct pt_regs' is a type mismatch for socket
			 * filter that should be using 'struct __sk_buff'.
			 */
			goto out;
	}

	ret = do_check(env);
out:
	/* check for NULL is necessary, since cur_state can be freed inside
	 * do_check() under memory pressure.
	 */
	if (env->cur_state) {
		free_verifier_state(env->cur_state, true);
		env->cur_state = NULL;
	}
	while (!pop_stack(env, NULL, NULL, false));
	if (!ret && pop_log)
		bpf_vlog_reset(&env->log, 0);
	free_states(env);
	if (ret)
		/* clean aux data in case subprog was rejected */
		sanitize_insn_aux_data(env);
	return ret;
}

Project: linux
File: syscall.c

static int bpf_prog_test_run(const union bpf_attr *attr,
			     union bpf_attr __user *uattr)
{
	struct bpf_prog *prog;
	int ret = -ENOTSUPP;

	if (CHECK_ATTR(BPF_PROG_TEST_RUN))
		return -EINVAL;

	if ((attr->test.ctx_size_in && !attr->test.ctx_in) ||
	    (!attr->test.ctx_size_in && attr->test.ctx_in))
		return -EINVAL;

	if ((attr->test.ctx_size_out && !attr->test.ctx_out) ||
	    (!attr->test.ctx_size_out && attr->test.ctx_out))
		return -EINVAL;

	prog = bpf_prog_get(attr->test.prog_fd);
	if (IS_ERR(prog))
		return PTR_ERR(prog);

	if (prog->aux->ops->test_run)
		ret = prog->aux->ops->test_run(prog, attr, uattr);

	bpf_prog_put(prog);
	return ret;
}

Project: linux
File: syscall.c

static struct bpf_prog *__bpf_prog_get(u32 ufd, enum bpf_prog_type *attach_type,
				       bool attach_drv)
{
	struct fd f = fdget(ufd);
	struct bpf_prog *prog;

	prog = ____bpf_prog_get(f);
	if (IS_ERR(prog))
		return prog;
	if (!bpf_prog_get_ok(prog, attach_type, attach_drv)) {
		prog = ERR_PTR(-EINVAL);
		goto out;
	}

	bpf_prog_inc(prog);
out:
	fdput(f);
	return prog;
}

Project: linux
File: syscall.c

static void __bpf_prog_put_rcu(struct rcu_head *rcu)
{
	struct bpf_prog_aux *aux = container_of(rcu, struct bpf_prog_aux, rcu);

	kvfree(aux->func_info);
	kfree(aux->func_info_aux);
	free_uid(aux->user);
	security_bpf_prog_free(aux);
	bpf_prog_free(aux->prog);
}

Project: linux
File: syscall.c

static int link_create(union bpf_attr *attr)
{
	enum bpf_prog_type ptype;
	struct bpf_prog *prog;
	int ret;

	if (CHECK_ATTR(BPF_LINK_CREATE))
		return -EINVAL;

	prog = bpf_prog_get(attr->link_create.prog_fd);
	if (IS_ERR(prog))
		return PTR_ERR(prog);

	ret = bpf_prog_attach_check_attach_type(prog,
						attr->link_create.attach_type);
	if (ret)
		goto out;

	if (prog->type == BPF_PROG_TYPE_EXT) {
		ret = tracing_bpf_link_attach(attr, prog);
		goto out;
	}

	ptype = attach_type_to_prog_type(attr->link_create.attach_type);
	if (ptype == BPF_PROG_TYPE_UNSPEC || ptype != prog->type) {
		ret = -EINVAL;
		goto out;
	}

	switch (ptype) {
	case BPF_PROG_TYPE_CGROUP_SKB:
	case BPF_PROG_TYPE_CGROUP_SOCK:
	case BPF_PROG_TYPE_CGROUP_SOCK_ADDR:
	case BPF_PROG_TYPE_SOCK_OPS:
	case BPF_PROG_TYPE_CGROUP_DEVICE:
	case BPF_PROG_TYPE_CGROUP_SYSCTL:
	case BPF_PROG_TYPE_CGROUP_SOCKOPT:
		ret = cgroup_bpf_link_attach(attr, prog);
		break;
	case BPF_PROG_TYPE_TRACING:
		ret = tracing_bpf_link_attach(attr, prog);
		break;
	case BPF_PROG_TYPE_FLOW_DISSECTOR:
	case BPF_PROG_TYPE_SK_LOOKUP:
		ret = netns_bpf_link_create(attr, prog);
		break;
#ifdef CONFIG_NET
	case BPF_PROG_TYPE_XDP:
		ret = bpf_xdp_link_attach(attr, prog);
		break;
#endif
	default:
		ret = -EINVAL;
	}

out:
	if (ret < 0)
		bpf_prog_put(prog);
	return ret;
}

Project: linux
File: syscall.c

int bpf_check_uarg_tail_zero(void __user *uaddr,
			     size_t expected_size,
			     size_t actual_size)
{
	unsigned char __user *addr = uaddr + expected_size;
	int res;

	if (unlikely(actual_size > PAGE_SIZE))	/* silly large */
		return -E2BIG;

	if (actual_size <= expected_size)
		return 0;

	res = check_zeroed_user(addr, actual_size - expected_size);
	if (res < 0)
		return res;
	return res ? 0 : -E2BIG;
}

Project: linux
File: syscall.c

void *bpf_map_kzalloc(const struct bpf_map *map, size_t size, gfp_t flags)
{
	struct mem_cgroup *old_memcg;
	void *ptr;

	old_memcg = set_active_memcg(map->memcg);
	ptr = kzalloc(size, flags | __GFP_ACCOUNT);
	set_active_memcg(old_memcg);

	return ptr;
}

Project: linux
File: syscall.c

static __poll_t bpf_map_poll(struct file *filp, struct poll_table_struct *pts)
{
	struct bpf_map *map = filp->private_data;

	if (map->ops->map_poll)
		return map->ops->map_poll(map, filp, pts);

	return EPOLLERR;
}

Project: linux
File: syscall.c

static int bpf_task_fd_query(const union bpf_attr *attr,
			     union bpf_attr __user *uattr)
{
	pid_t pid = attr->task_fd_query.pid;
	u32 fd = attr->task_fd_query.fd;
	const struct perf_event *event;
	struct task_struct *task;
	struct file *file;
	int err;

	if (CHECK_ATTR(BPF_TASK_FD_QUERY))
		return -EINVAL;

	if (!capable(CAP_SYS_ADMIN))
		return -EPERM;

	if (attr->task_fd_query.flags != 0)
		return -EINVAL;

	task = get_pid_task(find_vpid(pid), PIDTYPE_PID);
	if (!task)
		return -ENOENT;

	err = 0;
	file = fget_task(task, fd);
	put_task_struct(task);
	if (!file)
		return -EBADF;

	if (file->f_op == &bpf_link_fops) {
		struct bpf_link *link = file->private_data;

		if (link->ops == &bpf_raw_tp_link_lops) {
			struct bpf_raw_tp_link *raw_tp =
				container_of(link, struct bpf_raw_tp_link, link);
			struct bpf_raw_event_map *btp = raw_tp->btp;

			err = bpf_task_fd_query_copy(attr, uattr,
						     raw_tp->link.prog->aux->id,
						     BPF_FD_TYPE_RAW_TRACEPOINT,
						     btp->tp->name, 0, 0);
			goto put_file;
		}
		goto out_not_supp;
	}

	event = perf_get_event(file);
	if (!IS_ERR(event)) {
		u64 probe_offset, probe_addr;
		u32 prog_id, fd_type;
		const char *buf;

		err = bpf_get_perf_event_info(event, &prog_id, &fd_type,
					      &buf, &probe_offset,
					      &probe_addr);
		if (!err)
			err = bpf_task_fd_query_copy(attr, uattr, prog_id,
						     fd_type, buf,
						     probe_offset,
						     probe_addr);
		goto put_file;
	}

out_not_supp:
	err = -ENOTSUPP;
put_file:
	fput(file);
	return err;
}

Project: linux
File: syscall.c

struct bpf_prog *bpf_prog_by_id(u32 id)
{
	struct bpf_prog *prog;

	if (!id)
		return ERR_PTR(-ENOENT);

	spin_lock_bh(&prog_idr_lock);
	prog = idr_find(&prog_idr, id);
	if (prog)
		prog = bpf_prog_inc_not_zero(prog);
	else
		prog = ERR_PTR(-ENOENT);
	spin_unlock_bh(&prog_idr_lock);
	return prog;
}

Project: linux
File: syscall.c

static int bpf_obj_get_next_id(const union bpf_attr *attr,
			       union bpf_attr __user *uattr,
			       struct idr *idr,
			       spinlock_t *lock)
{
	u32 next_id = attr->start_id;
	int err = 0;

	if (CHECK_ATTR(BPF_OBJ_GET_NEXT_ID) || next_id >= INT_MAX)
		return -EINVAL;

	if (!capable(CAP_SYS_ADMIN))
		return -EPERM;

	next_id++;
	spin_lock_bh(lock);
	if (!idr_get_next(idr, &next_id))
		err = -ENOENT;
	spin_unlock_bh(lock);

	if (!err)
		err = put_user(next_id, &uattr->next_id);

	return err;
}

Project: linux
File: syscall.c

static void __bpf_map_put(struct bpf_map *map, bool do_idr_lock)
{
	if (atomic64_dec_and_test(&map->refcnt)) {
		/* bpf_map_free_id() must be called first */
		bpf_map_free_id(map, do_idr_lock);
		btf_put(map->btf);
		INIT_WORK(&map->work, bpf_map_free_deferred);
		schedule_work(&map->work);
	}
}

Project: linux
File: syscall.c

void bpf_map_put_with_uref(struct bpf_map *map)
{
	bpf_map_put_uref(map);
	bpf_map_put(map);
}

Project: linux
File: verifier.c

static int adjust_scalar_min_max_vals(struct bpf_verifier_env *env,
				      struct bpf_insn *insn,
				      struct bpf_reg_state *dst_reg,
				      struct bpf_reg_state src_reg)
{
	struct bpf_reg_state *regs = cur_regs(env);
	u8 opcode = BPF_OP(insn->code);
	bool src_known;
	s64 smin_val, smax_val;
	u64 umin_val, umax_val;
	s32 s32_min_val, s32_max_val;
	u32 u32_min_val, u32_max_val;
	u64 insn_bitness = (BPF_CLASS(insn->code) == BPF_ALU64) ? 64 : 32;
	u32 dst = insn->dst_reg;
	int ret;
	bool alu32 = (BPF_CLASS(insn->code) != BPF_ALU64);

	smin_val = src_reg.smin_value;
	smax_val = src_reg.smax_value;
	umin_val = src_reg.umin_value;
	umax_val = src_reg.umax_value;

	s32_min_val = src_reg.s32_min_value;
	s32_max_val = src_reg.s32_max_value;
	u32_min_val = src_reg.u32_min_value;
	u32_max_val = src_reg.u32_max_value;

	if (alu32) {
		src_known = tnum_subreg_is_const(src_reg.var_off);
		if ((src_known &&
		     (s32_min_val != s32_max_val || u32_min_val != u32_max_val)) ||
		    s32_min_val > s32_max_val || u32_min_val > u32_max_val) {
			/* Taint dst register if offset had invalid bounds
			 * derived from e.g. dead branches.
			 */
			__mark_reg_unknown(env, dst_reg);
			return 0;
		}
	} else {
		src_known = tnum_is_const(src_reg.var_off);
		if ((src_known &&
		     (smin_val != smax_val || umin_val != umax_val)) ||
		    smin_val > smax_val || umin_val > umax_val) {
			/* Taint dst register if offset had invalid bounds
			 * derived from e.g. dead branches.
			 */
			__mark_reg_unknown(env, dst_reg);
			return 0;
		}
	}

	if (!src_known &&
	    opcode != BPF_ADD && opcode != BPF_SUB && opcode != BPF_AND) {
		__mark_reg_unknown(env, dst_reg);
		return 0;
	}

	/* Calculate sign/unsigned bounds and tnum for alu32 and alu64 bit ops.
	 * There are two classes of instructions: The first class we track both
	 * alu32 and alu64 sign/unsigned bounds independently this provides the
	 * greatest amount of precision when alu operations are mixed with jmp32
	 * operations. These operations are BPF_ADD, BPF_SUB, BPF_MUL, BPF_ADD,
	 * and BPF_OR. This is possible because these ops have fairly easy to
	 * understand and calculate behavior in both 32-bit and 64-bit alu ops.
	 * See alu32 verifier tests for examples. The second class of
	 * operations, BPF_LSH, BPF_RSH, and BPF_ARSH, however are not so easy
	 * with regards to tracking sign/unsigned bounds because the bits may
	 * cross subreg boundaries in the alu64 case. When this happens we mark
	 * the reg unbounded in the subreg bound space and use the resulting
	 * tnum to calculate an approximation of the sign/unsigned bounds.
	 */
	switch (opcode) {
	case BPF_ADD:
		ret = sanitize_val_alu(env, insn);
		if (ret < 0) {
			verbose(env, "R%d tried to add from different pointers or scalars\n", dst);
			return ret;
		}
		scalar32_min_max_add(dst_reg, &src_reg);
		scalar_min_max_add(dst_reg, &src_reg);
		dst_reg->var_off = tnum_add(dst_reg->var_off, src_reg.var_off);
		break;
	case BPF_SUB:
		ret = sanitize_val_alu(env, insn);
		if (ret < 0) {
			verbose(env, "R%d tried to sub from different pointers or scalars\n", dst);
			return ret;
		}
		scalar32_min_max_sub(dst_reg, &src_reg);
		scalar_min_max_sub(dst_reg, &src_reg);
		dst_reg->var_off = tnum_sub(dst_reg->var_off, src_reg.var_off);
		break;
	case BPF_MUL:
		dst_reg->var_off = tnum_mul(dst_reg->var_off, src_reg.var_off);
		scalar32_min_max_mul(dst_reg, &src_reg);
		scalar_min_max_mul(dst_reg, &src_reg);
		break;
	case BPF_AND:
		dst_reg->var_off = tnum_and(dst_reg->var_off, src_reg.var_off);
		scalar32_min_max_and(dst_reg, &src_reg);
		scalar_min_max_and(dst_reg, &src_reg);
		break;
	case BPF_OR:
		dst_reg->var_off = tnum_or(dst_reg->var_off, src_reg.var_off);
		scalar32_min_max_or(dst_reg, &src_reg);
		scalar_min_max_or(dst_reg, &src_reg);
		break;
	case BPF_XOR:
		dst_reg->var_off = tnum_xor(dst_reg->var_off, src_reg.var_off);
		scalar32_min_max_xor(dst_reg, &src_reg);
		scalar_min_max_xor(dst_reg, &src_reg);
		break;
	case BPF_LSH:
		if (umax_val >= insn_bitness) {
			/* Shifts greater than 31 or 63 are undefined.
			 * This includes shifts by a negative number.
			 */
			mark_reg_unknown(env, regs, insn->dst_reg);
			break;
		}
		if (alu32)
			scalar32_min_max_lsh(dst_reg, &src_reg);
		else
			scalar_min_max_lsh(dst_reg, &src_reg);
		break;
	case BPF_RSH:
		if (umax_val >= insn_bitness) {
			/* Shifts greater than 31 or 63 are undefined.
			 * This includes shifts by a negative number.
			 */
			mark_reg_unknown(env, regs, insn->dst_reg);
			break;
		}
		if (alu32)
			scalar32_min_max_rsh(dst_reg, &src_reg);
		else
			scalar_min_max_rsh(dst_reg, &src_reg);
		break;
	case BPF_ARSH:
		if (umax_val >= insn_bitness) {
			/* Shifts greater than 31 or 63 are undefined.
			 * This includes shifts by a negative number.
			 */
			mark_reg_unknown(env, regs, insn->dst_reg);
			break;
		}
		if (alu32)
			scalar32_min_max_arsh(dst_reg, &src_reg);
		else
			scalar_min_max_arsh(dst_reg, &src_reg);
		break;
	default:
		mark_reg_unknown(env, regs, insn->dst_reg);
		break;
	}

	/* ALU32 ops are zero extended into 64bit register */
	if (alu32)
		zext_32_to_64(dst_reg);

	__update_reg_bounds(dst_reg);
	__reg_deduce_bounds(dst_reg);
	__reg_bound_offset(dst_reg);
	return 0;
}

Project: linux
File: syscall.c

static void bpf_link_free_id(int id)
{
	if (!id)
		return;

	spin_lock_bh(&link_idr_lock);
	idr_remove(&link_idr, id);
	spin_unlock_bh(&link_idr_lock);
}

Project: linux
File: syscall.c

static void bpf_link_show_fdinfo(struct seq_file *m, struct file *filp)
{
	const struct bpf_link *link = filp->private_data;
	const struct bpf_prog *prog = link->prog;
	char prog_tag[sizeof(prog->tag) * 2 + 1] = { };

	bin2hex(prog_tag, prog->tag, sizeof(prog->tag));
	seq_printf(m,
		   "link_type:\t%s\n"
		   "link_id:\t%u\n"
		   "prog_tag:\t%s\n"
		   "prog_id:\t%u\n",
		   bpf_link_type_strs[link->type],
		   link->id,
		   prog_tag,
		   prog->aux->id);
	if (link->ops->show_fdinfo)
		link->ops->show_fdinfo(link, m);
}

Project: linux
File: syscall.c

static void bpf_tracing_link_release(struct bpf_link *link)
{
	struct bpf_tracing_link *tr_link =
		container_of(link, struct bpf_tracing_link, link);

	WARN_ON_ONCE(bpf_trampoline_unlink_prog(link->prog,
						tr_link->trampoline));

	bpf_trampoline_put(tr_link->trampoline);

	/* tgt_prog is NULL if target is a kernel function */
	if (tr_link->tgt_prog)
		bpf_prog_put(tr_link->tgt_prog);
}

Project: linux
File: syscall.c

static int bpf_prog_get_info_by_fd(struct file *file,
				   struct bpf_prog *prog,
				   const union bpf_attr *attr,
				   union bpf_attr __user *uattr)
{
	struct bpf_prog_info __user *uinfo = u64_to_user_ptr(attr->info.info);
	struct bpf_prog_info info;
	u32 info_len = attr->info.info_len;
	struct bpf_prog_stats stats;
	char __user *uinsns;
	u32 ulen;
	int err;

	err = bpf_check_uarg_tail_zero(uinfo, sizeof(info), info_len);
	if (err)
		return err;
	info_len = min_t(u32, sizeof(info), info_len);

	memset(&info, 0, sizeof(info));
	if (copy_from_user(&info, uinfo, info_len))
		return -EFAULT;

	info.type = prog->type;
	info.id = prog->aux->id;
	info.load_time = prog->aux->load_time;
	info.created_by_uid = from_kuid_munged(current_user_ns(),
					       prog->aux->user->uid);
	info.gpl_compatible = prog->gpl_compatible;

	memcpy(info.tag, prog->tag, sizeof(prog->tag));
	memcpy(info.name, prog->aux->name, sizeof(prog->aux->name));

	mutex_lock(&prog->aux->used_maps_mutex);
	ulen = info.nr_map_ids;
	info.nr_map_ids = prog->aux->used_map_cnt;
	ulen = min_t(u32, info.nr_map_ids, ulen);
	if (ulen) {
		u32 __user *user_map_ids = u64_to_user_ptr(info.map_ids);
		u32 i;

		for (i = 0; i < ulen; i++)
			if (put_user(prog->aux->used_maps[i]->id,
				     &user_map_ids[i])) {
				mutex_unlock(&prog->aux->used_maps_mutex);
				return -EFAULT;
			}
	}
	mutex_unlock(&prog->aux->used_maps_mutex);

	err = set_info_rec_size(&info);
	if (err)
		return err;

	bpf_prog_get_stats(prog, &stats);
	info.run_time_ns = stats.nsecs;
	info.run_cnt = stats.cnt;
	info.recursion_misses = stats.misses;

	if (!bpf_capable()) {
		info.jited_prog_len = 0;
		info.xlated_prog_len = 0;
		info.nr_jited_ksyms = 0;
		info.nr_jited_func_lens = 0;
		info.nr_func_info = 0;
		info.nr_line_info = 0;
		info.nr_jited_line_info = 0;
		goto done;
	}

	ulen = info.xlated_prog_len;
	info.xlated_prog_len = bpf_prog_insn_size(prog);
	if (info.xlated_prog_len && ulen) {
		struct bpf_insn *insns_sanitized;
		bool fault;

		if (prog->blinded && !bpf_dump_raw_ok(file->f_cred)) {
			info.xlated_prog_insns = 0;
			goto done;
		}
		insns_sanitized = bpf_insn_prepare_dump(prog, file->f_cred);
		if (!insns_sanitized)
			return -ENOMEM;
		uinsns = u64_to_user_ptr(info.xlated_prog_insns);
		ulen = min_t(u32, info.xlated_prog_len, ulen);
		fault = copy_to_user(uinsns, insns_sanitized, ulen);
		kfree(insns_sanitized);
		if (fault)
			return -EFAULT;
	}

	if (bpf_prog_is_dev_bound(prog->aux)) {
		err = bpf_prog_offload_info_fill(&info, prog);
		if (err)
			return err;
		goto done;
	}

	/* NOTE: the following code is supposed to be skipped for offload.
	 * bpf_prog_offload_info_fill() is the place to fill similar fields
	 * for offload.
	 */
	ulen = info.jited_prog_len;
	if (prog->aux->func_cnt) {
		u32 i;

		info.jited_prog_len = 0;
		for (i = 0; i < prog->aux->func_cnt; i++)
			info.jited_prog_len += prog->aux->func[i]->jited_len;
	} else {
		info.jited_prog_len = prog->jited_len;
	}

	if (info.jited_prog_len && ulen) {
		if (bpf_dump_raw_ok(file->f_cred)) {
			uinsns = u64_to_user_ptr(info.jited_prog_insns);
			ulen = min_t(u32, info.jited_prog_len, ulen);

			/* for multi-function programs, copy the JITed
			 * instructions for all the functions
			 */
			if (prog->aux->func_cnt) {
				u32 len, free, i;
				u8 *img;

				free = ulen;
				for (i = 0; i < prog->aux->func_cnt; i++) {
					len = prog->aux->func[i]->jited_len;
					len = min_t(u32, len, free);
					img = (u8 *) prog->aux->func[i]->bpf_func;
					if (copy_to_user(uinsns, img, len))
						return -EFAULT;
					uinsns += len;
					free -= len;
					if (!free)
						break;
				}
			} else {
				if (copy_to_user(uinsns, prog->bpf_func, ulen))
					return -EFAULT;
			}
		} else {
			info.jited_prog_insns = 0;
		}
	}

	ulen = info.nr_jited_ksyms;
	info.nr_jited_ksyms = prog->aux->func_cnt ? : 1;
	if (ulen) {
		if (bpf_dump_raw_ok(file->f_cred)) {
			unsigned long ksym_addr;
			u64 __user *user_ksyms;
			u32 i;

			/* copy the address of the kernel symbol
			 * corresponding to each function
			 */
			ulen = min_t(u32, info.nr_jited_ksyms, ulen);
			user_ksyms = u64_to_user_ptr(info.jited_ksyms);
			if (prog->aux->func_cnt) {
				for (i = 0; i < ulen; i++) {
					ksym_addr = (unsigned long)
						prog->aux->func[i]->bpf_func;
					if (put_user((u64) ksym_addr,
						     &user_ksyms[i]))
						return -EFAULT;
				}
			} else {
				ksym_addr = (unsigned long) prog->bpf_func;
				if (put_user((u64) ksym_addr, &user_ksyms[0]))
					return -EFAULT;
			}
		} else {
			info.jited_ksyms = 0;
		}
	}

	ulen = info.nr_jited_func_lens;
	info.nr_jited_func_lens = prog->aux->func_cnt ? : 1;
	if (ulen) {
		if (bpf_dump_raw_ok(file->f_cred)) {
			u32 __user *user_lens;
			u32 func_len, i;

			/* copy the JITed image lengths for each function */
			ulen = min_t(u32, info.nr_jited_func_lens, ulen);
			user_lens = u64_to_user_ptr(info.jited_func_lens);
			if (prog->aux->func_cnt) {
				for (i = 0; i < ulen; i++) {
					func_len =
						prog->aux->func[i]->jited_len;
					if (put_user(func_len, &user_lens[i]))
						return -EFAULT;
				}
			} else {
				func_len = prog->jited_len;
				if (put_user(func_len, &user_lens[0]))
					return -EFAULT;
			}
		} else {
			info.jited_func_lens = 0;
		}
	}

	if (prog->aux->btf)
		info.btf_id = btf_obj_id(prog->aux->btf);

	ulen = info.nr_func_info;
	info.nr_func_info = prog->aux->func_info_cnt;
	if (info.nr_func_info && ulen) {
		char __user *user_finfo;

		user_finfo = u64_to_user_ptr(info.func_info);
		ulen = min_t(u32, info.nr_func_info, ulen);
		if (copy_to_user(user_finfo, prog->aux->func_info,
				 info.func_info_rec_size * ulen))
			return -EFAULT;
	}

	ulen = info.nr_line_info;
	info.nr_line_info = prog->aux->nr_linfo;
	if (info.nr_line_info && ulen) {
		__u8 __user *user_linfo;

		user_linfo = u64_to_user_ptr(info.line_info);
		ulen = min_t(u32, info.nr_line_info, ulen);
		if (copy_to_user(user_linfo, prog->aux->linfo,
				 info.line_info_rec_size * ulen))
			return -EFAULT;
	}

	ulen = info.nr_jited_line_info;
	if (prog->aux->jited_linfo)
		info.nr_jited_line_info = prog->aux->nr_linfo;
	else
		info.nr_jited_line_info = 0;
	if (info.nr_jited_line_info && ulen) {
		if (bpf_dump_raw_ok(file->f_cred)) {
			__u64 __user *user_linfo;
			u32 i;

			user_linfo = u64_to_user_ptr(info.jited_line_info);
			ulen = min_t(u32, info.nr_jited_line_info, ulen);
			for (i = 0; i < ulen; i++) {
				if (put_user((__u64)(long)prog->aux->jited_linfo[i],
					     &user_linfo[i]))
					return -EFAULT;
			}
		} else {
			info.jited_line_info = 0;
		}
	}

	ulen = info.nr_prog_tags;
	info.nr_prog_tags = prog->aux->func_cnt ? : 1;
	if (ulen) {
		__u8 __user (*user_prog_tags)[BPF_TAG_SIZE];
		u32 i;

		user_prog_tags = u64_to_user_ptr(info.prog_tags);
		ulen = min_t(u32, info.nr_prog_tags, ulen);
		if (prog->aux->func_cnt) {
			for (i = 0; i < ulen; i++) {
				if (copy_to_user(user_prog_tags[i],
						 prog->aux->func[i]->tag,
						 BPF_TAG_SIZE))
					return -EFAULT;
			}
		} else {
			if (copy_to_user(user_prog_tags[0],
					 prog->tag, BPF_TAG_SIZE))
				return -EFAULT;
		}
	}

done:
	if (copy_to_user(uinfo, &info, info_len) ||
	    put_user(info_len, &uattr->info.info_len))
		return -EFAULT;

	return 0;
}

Project: linux
File: verifier.c

static bool is_spillable_regtype(enum bpf_reg_type type)
{
	switch (type) {
	case PTR_TO_MAP_VALUE:
	case PTR_TO_MAP_VALUE_OR_NULL:
	case PTR_TO_STACK:
	case PTR_TO_CTX:
	case PTR_TO_PACKET:
	case PTR_TO_PACKET_META:
	case PTR_TO_PACKET_END:
	case PTR_TO_FLOW_KEYS:
	case CONST_PTR_TO_MAP:
	case PTR_TO_SOCKET:
	case PTR_TO_SOCKET_OR_NULL:
	case PTR_TO_SOCK_COMMON:
	case PTR_TO_SOCK_COMMON_OR_NULL:
	case PTR_TO_TCP_SOCK:
	case PTR_TO_TCP_SOCK_OR_NULL:
	case PTR_TO_XDP_SOCK:
	case PTR_TO_BTF_ID:
	case PTR_TO_BTF_ID_OR_NULL:
	case PTR_TO_RDONLY_BUF:
	case PTR_TO_RDONLY_BUF_OR_NULL:
	case PTR_TO_RDWR_BUF:
	case PTR_TO_RDWR_BUF_OR_NULL:
	case PTR_TO_PERCPU_BTF_ID:
	case PTR_TO_MEM:
	case PTR_TO_MEM_OR_NULL:
		return true;
	default:
		return false;
	}
}

Project: linux
File: syscall.c

void bpf_prog_inc(struct bpf_prog *prog)
{
	atomic64_inc(&prog->aux->refcnt);
}

Project: linux
File: syscall.c

static void bpf_map_save_memcg(struct bpf_map *map)
{
}

Project: linux
File: verifier.c

static bool arg_type_may_be_null(enum bpf_arg_type type)
{
	return type == ARG_PTR_TO_MAP_VALUE_OR_NULL ||
	       type == ARG_PTR_TO_MEM_OR_NULL ||
	       type == ARG_PTR_TO_CTX_OR_NULL ||
	       type == ARG_PTR_TO_SOCKET_OR_NULL ||
	       type == ARG_PTR_TO_ALLOC_MEM_OR_NULL;
}

Project: linux
File: syscall.c

void bpf_prog_free_id(struct bpf_prog *prog, bool do_idr_lock)
{
	/* cBPF to eBPF migrations are currently not in the idr store.
	 * Offloaded programs are removed from the store when their device
	 * disappears - even if someone grabs an fd to them they are unusable,
	 * simply waiting for refcnt to drop to be freed.
	 */
	if (!prog->aux->id)
		return;

	if (do_idr_lock)
		spin_lock_bh(&prog_idr_lock);
	else
		__acquire(&prog_idr_lock);

	idr_remove(&prog_idr, prog->aux->id);
	prog->aux->id = 0;

	if (do_idr_lock)
		spin_unlock_bh(&prog_idr_lock);
	else
		__release(&prog_idr_lock);
}

Project: linux
File: syscall.c

struct bpf_link *bpf_link_by_id(u32 id)
{
	struct bpf_link *link;

	if (!id)
		return ERR_PTR(-ENOENT);

	spin_lock_bh(&link_idr_lock);
	/* before link is "settled", ID is 0, pretend it doesn't exist yet */
	link = idr_find(&link_idr, id);
	if (link) {
		if (link->id)
			link = bpf_link_inc_not_zero(link);
		else
			link = ERR_PTR(-EAGAIN);
	} else {
		link = ERR_PTR(-ENOENT);
	}
	spin_unlock_bh(&link_idr_lock);
	return link;
}

Project: linux
File: syscall.c

static void __bpf_prog_put(struct bpf_prog *prog, bool do_idr_lock)
{
	if (atomic64_dec_and_test(&prog->aux->refcnt)) {
		perf_event_bpf_event(prog, PERF_BPF_EVENT_PROG_UNLOAD, 0);
		bpf_audit_prog(prog, BPF_AUDIT_UNLOAD);
		/* bpf_prog_free_id() must be called first */
		bpf_prog_free_id(prog, do_idr_lock);
		__bpf_prog_put_noref(prog, true);
	}
}

Project: linux
File: verifier.c

static int check_max_stack_depth(struct bpf_verifier_env *env)
{
	int depth = 0, frame = 0, idx = 0, i = 0, subprog_end;
	struct bpf_subprog_info *subprog = env->subprog_info;
	struct bpf_insn *insn = env->prog->insnsi;
	bool tail_call_reachable = false;
	int ret_insn[MAX_CALL_FRAMES];
	int ret_prog[MAX_CALL_FRAMES];
	int j;

process_func:
	/* protect against potential stack overflow that might happen when
	 * bpf2bpf calls get combined with tailcalls. Limit the caller's stack
	 * depth for such case down to 256 so that the worst case scenario
	 * would result in 8k stack size (32 which is tailcall limit * 256 =
	 * 8k).
	 *
	 * To get the idea what might happen, see an example:
	 * func1 -> sub rsp, 128
	 *  subfunc1 -> sub rsp, 256
	 *  tailcall1 -> add rsp, 256
	 *   func2 -> sub rsp, 192 (total stack size = 128 + 192 = 320)
	 *   subfunc2 -> sub rsp, 64
	 *   subfunc22 -> sub rsp, 128
	 *   tailcall2 -> add rsp, 128
	 *    func3 -> sub rsp, 32 (total stack size 128 + 192 + 64 + 32 = 416)
	 *
	 * tailcall will unwind the current stack frame but it will not get rid
	 * of caller's stack as shown on the example above.
	 */
	if (idx && subprog[idx].has_tail_call && depth >= 256) {
		verbose(env,
			"tail_calls are not allowed when call stack of previous frames is %d bytes. Too large\n",
			depth);
		return -EACCES;
	}
	/* round up to 32-bytes, since this is granularity
	 * of interpreter stack size
	 */
	depth += round_up(max_t(u32, subprog[idx].stack_depth, 1), 32);
	if (depth > MAX_BPF_STACK) {
		verbose(env, "combined stack size of %d calls is %d. Too large\n",
			frame + 1, depth);
		return -EACCES;
	}
continue_func:
	subprog_end = subprog[idx + 1].start;
	for (; i < subprog_end; i++) {
		if (!bpf_pseudo_call(insn + i))
			continue;
		/* remember insn and function to return to */
		ret_insn[frame] = i + 1;
		ret_prog[frame] = idx;

		/* find the callee */
		i = i + insn[i].imm + 1;
		idx = find_subprog(env, i);
		if (idx < 0) {
			WARN_ONCE(1, "verifier bug. No program starts at insn %d\n",
				  i);
			return -EFAULT;
		}

		if (subprog[idx].has_tail_call)
			tail_call_reachable = true;

		frame++;
		if (frame >= MAX_CALL_FRAMES) {
			verbose(env, "the call stack of %d frames is too deep !\n",
				frame);
			return -E2BIG;
		}
		goto process_func;
	}
	/* if tail call got detected across bpf2bpf calls then mark each of the
	 * currently present subprog frames as tail call reachable subprogs;
	 * this info will be utilized by JIT so that we will be preserving the
	 * tail call counter throughout bpf2bpf calls combined with tailcalls
	 */
	if (tail_call_reachable)
		for (j = 0; j < frame; j++)
			subprog[ret_prog[j]].tail_call_reachable = true;

	/* end of for() loop means the last insn of the 'subprog'
	 * was reached. Doesn't matter whether it was JA or EXIT
	 */
	if (frame == 0)
		return 0;
	depth -= round_up(max_t(u32, subprog[idx].stack_depth, 1), 32);
	frame--;
	i = ret_insn[frame];
	idx = ret_prog[frame];
	goto continue_func;
}

Project: linux
File: syscall.c

void bpf_map_area_free(void *area)
{
	kvfree(area);
}

Project: linux
File: syscall.c

static void bpf_raw_tp_link_show_fdinfo(const struct bpf_link *link,
					struct seq_file *seq)
{
	struct bpf_raw_tp_link *raw_tp_link =
		container_of(link, struct bpf_raw_tp_link, link);

	seq_printf(seq,
		   "tp_name:\t%s\n",
		   raw_tp_link->btp->tp->name);
}

Project: linux
File: syscall.c

static int bpf_map_release(struct inode *inode, struct file *filp)
{
	struct bpf_map *map = filp->private_data;

	if (map->ops->map_release)
		map->ops->map_release(map, filp);

	bpf_map_put_with_uref(map);
	return 0;
}

Project: linux
File: syscall.c

static int map_delete_elem(union bpf_attr *attr)
{
	void __user *ukey = u64_to_user_ptr(attr->key);
	int ufd = attr->map_fd;
	struct bpf_map *map;
	struct fd f;
	void *key;
	int err;

	if (CHECK_ATTR(BPF_MAP_DELETE_ELEM))
		return -EINVAL;

	f = fdget(ufd);
	map = __bpf_map_get(f);
	if (IS_ERR(map))
		return PTR_ERR(map);
	if (!(map_get_sys_perms(map, f) & FMODE_CAN_WRITE)) {
		err = -EPERM;
		goto err_put;
	}

	key = __bpf_copy_key(ukey, map->key_size);
	if (IS_ERR(key)) {
		err = PTR_ERR(key);
		goto err_put;
	}

	if (bpf_map_is_dev_bound(map)) {
		err = bpf_map_offload_delete_elem(map, key);
		goto out;
	} else if (IS_FD_PROG_ARRAY(map) ||
		   map->map_type == BPF_MAP_TYPE_STRUCT_OPS) {
		/* These maps require sleepable context */
		err = map->ops->map_delete_elem(map, key);
		goto out;
	}

	bpf_disable_instrumentation();
	rcu_read_lock();
	err = map->ops->map_delete_elem(map, key);
	rcu_read_unlock();
	bpf_enable_instrumentation();
	maybe_wait_bpf_programs(map);
out:
	kfree(key);
err_put:
	fdput(f);
	return err;
}

Project: linux
File: verifier.c

static int adjust_ptr_min_max_vals(struct bpf_verifier_env *env,
				   struct bpf_insn *insn,
				   const struct bpf_reg_state *ptr_reg,
				   const struct bpf_reg_state *off_reg)
{
	struct bpf_verifier_state *vstate = env->cur_state;
	struct bpf_func_state *state = vstate->frame[vstate->curframe];
	struct bpf_reg_state *regs = state->regs, *dst_reg;
	bool known = tnum_is_const(off_reg->var_off);
	s64 smin_val = off_reg->smin_value, smax_val = off_reg->smax_value,
	    smin_ptr = ptr_reg->smin_value, smax_ptr = ptr_reg->smax_value;
	u64 umin_val = off_reg->umin_value, umax_val = off_reg->umax_value,
	    umin_ptr = ptr_reg->umin_value, umax_ptr = ptr_reg->umax_value;
	u32 dst = insn->dst_reg, src = insn->src_reg;
	u8 opcode = BPF_OP(insn->code);
	int ret;

	dst_reg = &regs[dst];

	if ((known && (smin_val != smax_val || umin_val != umax_val)) ||
	    smin_val > smax_val || umin_val > umax_val) {
		/* Taint dst register if offset had invalid bounds derived from
		 * e.g. dead branches.
		 */
		__mark_reg_unknown(env, dst_reg);
		return 0;
	}

	if (BPF_CLASS(insn->code) != BPF_ALU64) {
		/* 32-bit ALU ops on pointers produce (meaningless) scalars */
		if (opcode == BPF_SUB && env->allow_ptr_leaks) {
			__mark_reg_unknown(env, dst_reg);
			return 0;
		}

		verbose(env,
			"R%d 32-bit pointer arithmetic prohibited\n",
			dst);
		return -EACCES;
	}

	switch (ptr_reg->type) {
	case PTR_TO_MAP_VALUE_OR_NULL:
		verbose(env, "R%d pointer arithmetic on %s prohibited, null-check it first\n",
			dst, reg_type_str[ptr_reg->type]);
		return -EACCES;
	case CONST_PTR_TO_MAP:
		/* smin_val represents the known value */
		if (known && smin_val == 0 && opcode == BPF_ADD)
			break;
		fallthrough;
	case PTR_TO_PACKET_END:
	case PTR_TO_SOCKET:
	case PTR_TO_SOCKET_OR_NULL:
	case PTR_TO_SOCK_COMMON:
	case PTR_TO_SOCK_COMMON_OR_NULL:
	case PTR_TO_TCP_SOCK:
	case PTR_TO_TCP_SOCK_OR_NULL:
	case PTR_TO_XDP_SOCK:
		verbose(env, "R%d pointer arithmetic on %s prohibited\n",
			dst, reg_type_str[ptr_reg->type]);
		return -EACCES;
	case PTR_TO_MAP_VALUE:
		if (!env->allow_ptr_leaks && !known && (smin_val < 0) != (smax_val < 0)) {
			verbose(env, "R%d has unknown scalar with mixed signed bounds, pointer arithmetic with it prohibited for !root\n",
				off_reg == dst_reg ? dst : src);
			return -EACCES;
		}
		fallthrough;
	default:
		break;
	}

	/* In case of 'scalar += pointer', dst_reg inherits pointer type and id.
	 * The id may be overwritten later if we create a new variable offset.
	 */
	dst_reg->type = ptr_reg->type;
	dst_reg->id = ptr_reg->id;

	if (!check_reg_sane_offset(env, off_reg, ptr_reg->type) ||
	    !check_reg_sane_offset(env, ptr_reg, ptr_reg->type))
		return -EINVAL;

	/* pointer types do not carry 32-bit bounds at the moment. */
	__mark_reg32_unbounded(dst_reg);

	switch (opcode) {
	case BPF_ADD:
		ret = sanitize_ptr_alu(env, insn, ptr_reg, dst_reg, smin_val < 0);
		if (ret < 0) {
			verbose(env, "R%d tried to add from different maps or paths\n", dst);
			return ret;
		}
		/* We can take a fixed offset as long as it doesn't overflow
		 * the s32 'off' field
		 */
		if (known && (ptr_reg->off + smin_val ==
			      (s64)(s32)(ptr_reg->off + smin_val))) {
			/* pointer += K.  Accumulate it into fixed offset */
			dst_reg->smin_value = smin_ptr;
			dst_reg->smax_value = smax_ptr;
			dst_reg->umin_value = umin_ptr;
			dst_reg->umax_value = umax_ptr;
			dst_reg->var_off = ptr_reg->var_off;
			dst_reg->off = ptr_reg->off + smin_val;
			dst_reg->raw = ptr_reg->raw;
			break;
		}
		/* A new variable offset is created.  Note that off_reg->off
		 * == 0, since it's a scalar.
		 * dst_reg gets the pointer type and since some positive
		 * integer value was added to the pointer, give it a new 'id'
		 * if it's a PTR_TO_PACKET.
		 * this creates a new 'base' pointer, off_reg (variable) gets
		 * added into the variable offset, and we copy the fixed offset
		 * from ptr_reg.
		 */
		if (signed_add_overflows(smin_ptr, smin_val) ||
		    signed_add_overflows(smax_ptr, smax_val)) {
			dst_reg->smin_value = S64_MIN;
			dst_reg->smax_value = S64_MAX;
		} else {
			dst_reg->smin_value = smin_ptr + smin_val;
			dst_reg->smax_value = smax_ptr + smax_val;
		}
		if (umin_ptr + umin_val < umin_ptr ||
		    umax_ptr + umax_val < umax_ptr) {
			dst_reg->umin_value = 0;
			dst_reg->umax_value = U64_MAX;
		} else {
			dst_reg->umin_value = umin_ptr + umin_val;
			dst_reg->umax_value = umax_ptr + umax_val;
		}
		dst_reg->var_off = tnum_add(ptr_reg->var_off, off_reg->var_off);
		dst_reg->off = ptr_reg->off;
		dst_reg->raw = ptr_reg->raw;
		if (reg_is_pkt_pointer(ptr_reg)) {
			dst_reg->id = ++env->id_gen;
			/* something was added to pkt_ptr, set range to zero */
			memset(&dst_reg->raw, 0, sizeof(dst_reg->raw));
		}
		break;
	case BPF_SUB:
		ret = sanitize_ptr_alu(env, insn, ptr_reg, dst_reg, smin_val < 0);
		if (ret < 0) {
			verbose(env, "R%d tried to sub from different maps or paths\n", dst);
			return ret;
		}
		if (dst_reg == off_reg) {
			/* scalar -= pointer.  Creates an unknown scalar */
			verbose(env, "R%d tried to subtract pointer from scalar\n",
				dst);
			return -EACCES;
		}
		/* We don't allow subtraction from FP, because (according to
		 * test_verifier.c test "invalid fp arithmetic", JITs might not
		 * be able to deal with it.
		 */
		if (ptr_reg->type == PTR_TO_STACK) {
			verbose(env, "R%d subtraction from stack pointer prohibited\n",
				dst);
			return -EACCES;
		}
		if (known && (ptr_reg->off - smin_val ==
			      (s64)(s32)(ptr_reg->off - smin_val))) {
			/* pointer -= K.  Subtract it from fixed offset */
			dst_reg->smin_value = smin_ptr;
			dst_reg->smax_value = smax_ptr;
			dst_reg->umin_value = umin_ptr;
			dst_reg->umax_value = umax_ptr;
			dst_reg->var_off = ptr_reg->var_off;
			dst_reg->id = ptr_reg->id;
			dst_reg->off = ptr_reg->off - smin_val;
			dst_reg->raw = ptr_reg->raw;
			break;
		}
		/* A new variable offset is created.  If the subtrahend is known
		 * nonnegative, then any reg->range we had before is still good.
		 */
		if (signed_sub_overflows(smin_ptr, smax_val) ||
		    signed_sub_overflows(smax_ptr, smin_val)) {
			/* Overflow possible, we know nothing */
			dst_reg->smin_value = S64_MIN;
			dst_reg->smax_value = S64_MAX;
		} else {
			dst_reg->smin_value = smin_ptr - smax_val;
			dst_reg->smax_value = smax_ptr - smin_val;
		}
		if (umin_ptr < umax_val) {
			/* Overflow possible, we know nothing */
			dst_reg->umin_value = 0;
			dst_reg->umax_value = U64_MAX;
		} else {
			/* Cannot overflow (as long as bounds are consistent) */
			dst_reg->umin_value = umin_ptr - umax_val;
			dst_reg->umax_value = umax_ptr - umin_val;
		}
		dst_reg->var_off = tnum_sub(ptr_reg->var_off, off_reg->var_off);
		dst_reg->off = ptr_reg->off;
		dst_reg->raw = ptr_reg->raw;
		if (reg_is_pkt_pointer(ptr_reg)) {
			dst_reg->id = ++env->id_gen;
			/* something was added to pkt_ptr, set range to zero */
			if (smin_val < 0)
				memset(&dst_reg->raw, 0, sizeof(dst_reg->raw));
		}
		break;
	case BPF_AND:
	case BPF_OR:
	case BPF_XOR:
		/* bitwise ops on pointers are troublesome, prohibit. */
		verbose(env, "R%d bitwise operator %s on pointer prohibited\n",
			dst, bpf_alu_string[opcode >> 4]);
		return -EACCES;
	default:
		/* other operators (e.g. MUL,LSH) produce non-pointer results */
		verbose(env, "R%d pointer arithmetic with %s operator prohibited\n",
			dst, bpf_alu_string[opcode >> 4]);
		return -EACCES;
	}

	if (!check_reg_sane_offset(env, dst_reg, ptr_reg->type))
		return -EINVAL;

	__update_reg_bounds(dst_reg);
	__reg_deduce_bounds(dst_reg);
	__reg_bound_offset(dst_reg);

	/* For unprivileged we require that resulting offset must be in bounds
	 * in order to be able to sanitize access later on.
	 */
	if (!env->bypass_spec_v1) {
		if (dst_reg->type == PTR_TO_MAP_VALUE &&
		    check_map_access(env, dst, dst_reg->off, 1, false)) {
			verbose(env, "R%d pointer arithmetic of map value goes out of range, "
				"prohibited for !root\n", dst);
			return -EACCES;
		} else if (dst_reg->type == PTR_TO_STACK &&
			   check_stack_access_for_ptr_arithmetic(
				   env, dst, dst_reg, dst_reg->off +
				   dst_reg->var_off.value)) {
			return -EACCES;
		}
	}

	return 0;
}

Project: linux
File: syscall.c

static int bpf_map_alloc_id(struct bpf_map *map)
{
	int id;

	idr_preload(GFP_KERNEL);
	spin_lock_bh(&map_idr_lock);
	id = idr_alloc_cyclic(&map_idr, map, 1, INT_MAX, GFP_ATOMIC);
	if (id > 0)
		map->id = id;
	spin_unlock_bh(&map_idr_lock);
	idr_preload_end();

	if (WARN_ON_ONCE(!id))
		return -ENOSPC;

	return id > 0 ? 0 : id;
}

Project: linux
File: syscall.c

static int bpf_obj_pin(const union bpf_attr *attr)
{
	if (CHECK_ATTR(BPF_OBJ) || attr->file_flags != 0)
		return -EINVAL;

	return bpf_obj_pin_user(attr->bpf_fd, u64_to_user_ptr(attr->pathname));
}

Project: linux
File: syscall.c

void bpf_link_put(struct bpf_link *link)
{
	if (!atomic64_dec_and_test(&link->refcnt))
		return;

	if (in_atomic()) {
		INIT_WORK(&link->work, bpf_link_put_deferred);
		schedule_work(&link->work);
	} else {
		bpf_link_free(link);
	}
}

Project: linux
File: verifier.c

static int fixup_bpf_calls(struct bpf_verifier_env *env)
{
	struct bpf_prog *prog = env->prog;
	bool expect_blinding = bpf_jit_blinding_enabled(prog);
	struct bpf_insn *insn = prog->insnsi;
	const struct bpf_func_proto *fn;
	const int insn_cnt = prog->len;
	const struct bpf_map_ops *ops;
	struct bpf_insn_aux_data *aux;
	struct bpf_insn insn_buf[16];
	struct bpf_prog *new_prog;
	struct bpf_map *map_ptr;
	int i, ret, cnt, delta = 0;

	for (i = 0; i < insn_cnt; i++, insn++) {
		if (insn->code == (BPF_ALU64 | BPF_MOD | BPF_X) ||
		    insn->code == (BPF_ALU64 | BPF_DIV | BPF_X) ||
		    insn->code == (BPF_ALU | BPF_MOD | BPF_X) ||
		    insn->code == (BPF_ALU | BPF_DIV | BPF_X)) {
			bool is64 = BPF_CLASS(insn->code) == BPF_ALU64;
			bool isdiv = BPF_OP(insn->code) == BPF_DIV;
			struct bpf_insn *patchlet;
			struct bpf_insn chk_and_div[] = {
				/* [R,W]x div 0 -> 0 */
				BPF_RAW_INSN((is64 ? BPF_JMP : BPF_JMP32) |
					     BPF_JNE | BPF_K, insn->src_reg,
					     0, 2, 0),
				BPF_ALU32_REG(BPF_XOR, insn->dst_reg, insn->dst_reg),
				BPF_JMP_IMM(BPF_JA, 0, 0, 1),
				*insn,
			};
			struct bpf_insn chk_and_mod[] = {
				/* [R,W]x mod 0 -> [R,W]x */
				BPF_RAW_INSN((is64 ? BPF_JMP : BPF_JMP32) |
					     BPF_JEQ | BPF_K, insn->src_reg,
					     0, 1 + (is64 ? 0 : 1), 0),
				*insn,
				BPF_JMP_IMM(BPF_JA, 0, 0, 1),
				BPF_MOV32_REG(insn->dst_reg, insn->dst_reg),
			};

			patchlet = isdiv ? chk_and_div : chk_and_mod;
			cnt = isdiv ? ARRAY_SIZE(chk_and_div) :
				      ARRAY_SIZE(chk_and_mod) - (is64 ? 2 : 0);

			new_prog = bpf_patch_insn_data(env, i + delta, patchlet, cnt);
			if (!new_prog)
				return -ENOMEM;

			delta    += cnt - 1;
			env->prog = prog = new_prog;
			insn      = new_prog->insnsi + i + delta;
			continue;
		}

		if (BPF_CLASS(insn->code) == BPF_LD &&
		    (BPF_MODE(insn->code) == BPF_ABS ||
		     BPF_MODE(insn->code) == BPF_IND)) {
			cnt = env->ops->gen_ld_abs(insn, insn_buf);
			if (cnt == 0 || cnt >= ARRAY_SIZE(insn_buf)) {
				verbose(env, "bpf verifier is misconfigured\n");
				return -EINVAL;
			}

			new_prog = bpf_patch_insn_data(env, i + delta, insn_buf, cnt);
			if (!new_prog)
				return -ENOMEM;

			delta    += cnt - 1;
			env->prog = prog = new_prog;
			insn      = new_prog->insnsi + i + delta;
			continue;
		}

		if (insn->code == (BPF_ALU64 | BPF_ADD | BPF_X) ||
		    insn->code == (BPF_ALU64 | BPF_SUB | BPF_X)) {
			const u8 code_add = BPF_ALU64 | BPF_ADD | BPF_X;
			const u8 code_sub = BPF_ALU64 | BPF_SUB | BPF_X;
			struct bpf_insn insn_buf[16];
			struct bpf_insn *patch = &insn_buf[0];
			bool issrc, isneg;
			u32 off_reg;

			aux = &env->insn_aux_data[i + delta];
			if (!aux->alu_state ||
			    aux->alu_state == BPF_ALU_NON_POINTER)
				continue;

			isneg = aux->alu_state & BPF_ALU_NEG_VALUE;
			issrc = (aux->alu_state & BPF_ALU_SANITIZE) ==
				BPF_ALU_SANITIZE_SRC;

			off_reg = issrc ? insn->src_reg : insn->dst_reg;
			if (isneg)
				*patch++ = BPF_ALU64_IMM(BPF_MUL, off_reg, -1);
			*patch++ = BPF_MOV32_IMM(BPF_REG_AX, aux->alu_limit - 1);
			*patch++ = BPF_ALU64_REG(BPF_SUB, BPF_REG_AX, off_reg);
			*patch++ = BPF_ALU64_REG(BPF_OR, BPF_REG_AX, off_reg);
			*patch++ = BPF_ALU64_IMM(BPF_NEG, BPF_REG_AX, 0);
			*patch++ = BPF_ALU64_IMM(BPF_ARSH, BPF_REG_AX, 63);
			if (issrc) {
				*patch++ = BPF_ALU64_REG(BPF_AND, BPF_REG_AX,
							 off_reg);
				insn->src_reg = BPF_REG_AX;
			} else {
				*patch++ = BPF_ALU64_REG(BPF_AND, off_reg,
							 BPF_REG_AX);
			}
			if (isneg)
				insn->code = insn->code == code_add ?
					     code_sub : code_add;
			*patch++ = *insn;
			if (issrc && isneg)
				*patch++ = BPF_ALU64_IMM(BPF_MUL, off_reg, -1);
			cnt = patch - insn_buf;

			new_prog = bpf_patch_insn_data(env, i + delta, insn_buf, cnt);
			if (!new_prog)
				return -ENOMEM;

			delta    += cnt - 1;
			env->prog = prog = new_prog;
			insn      = new_prog->insnsi + i + delta;
			continue;
		}

		if (insn->code != (BPF_JMP | BPF_CALL))
			continue;
		if (insn->src_reg == BPF_PSEUDO_CALL)
			continue;

		if (insn->imm == BPF_FUNC_get_route_realm)
			prog->dst_needed = 1;
		if (insn->imm == BPF_FUNC_get_prandom_u32)
			bpf_user_rnd_init_once();
		if (insn->imm == BPF_FUNC_override_return)
			prog->kprobe_override = 1;
		if (insn->imm == BPF_FUNC_tail_call) {
			/* If we tail call into other programs, we
			 * cannot make any assumptions since they can
			 * be replaced dynamically during runtime in
			 * the program array.
			 */
			prog->cb_access = 1;
			if (!allow_tail_call_in_subprogs(env))
				prog->aux->stack_depth = MAX_BPF_STACK;
			prog->aux->max_pkt_offset = MAX_PACKET_OFF;

			/* mark bpf_tail_call as different opcode to avoid
			 * conditional branch in the interpeter for every normal
			 * call and to prevent accidental JITing by JIT compiler
			 * that doesn't support bpf_tail_call yet
			 */
			insn->imm = 0;
			insn->code = BPF_JMP | BPF_TAIL_CALL;

			aux = &env->insn_aux_data[i + delta];
			if (env->bpf_capable && !expect_blinding &&
			    prog->jit_requested &&
			    !bpf_map_key_poisoned(aux) &&
			    !bpf_map_ptr_poisoned(aux) &&
			    !bpf_map_ptr_unpriv(aux)) {
				struct bpf_jit_poke_descriptor desc = {
					.reason = BPF_POKE_REASON_TAIL_CALL,
					.tail_call.map = BPF_MAP_PTR(aux->map_ptr_state),
					.tail_call.key = bpf_map_key_immediate(aux),
					.insn_idx = i + delta,
				};

				ret = bpf_jit_add_poke_descriptor(prog, &desc);
				if (ret < 0) {
					verbose(env, "adding tail call poke descriptor failed\n");
					return ret;
				}

				insn->imm = ret + 1;
				continue;
			}

			if (!bpf_map_ptr_unpriv(aux))
				continue;

			/* instead of changing every JIT dealing with tail_call
			 * emit two extra insns:
			 * if (index >= max_entries) goto out;
			 * index &= array->index_mask;
			 * to avoid out-of-bounds cpu speculation
			 */
			if (bpf_map_ptr_poisoned(aux)) {
				verbose(env, "tail_call abusing map_ptr\n");
				return -EINVAL;
			}

			map_ptr = BPF_MAP_PTR(aux->map_ptr_state);
			insn_buf[0] = BPF_JMP_IMM(BPF_JGE, BPF_REG_3,
						  map_ptr->max_entries, 2);
			insn_buf[1] = BPF_ALU32_IMM(BPF_AND, BPF_REG_3,
						    container_of(map_ptr,
								 struct bpf_array,
								 map)->index_mask);
			insn_buf[2] = *insn;
			cnt = 3;
			new_prog = bpf_patch_insn_data(env, i + delta, insn_buf, cnt);
			if (!new_prog)
				return -ENOMEM;

			delta    += cnt - 1;
			env->prog = prog = new_prog;
			insn      = new_prog->insnsi + i + delta;
			continue;
		}

		/* BPF_EMIT_CALL() assumptions in some of the map_gen_lookup
		 * and other inlining handlers are currently limited to 64 bit
		 * only.
		 */
		if (prog->jit_requested && BITS_PER_LONG == 64 &&
		    (insn->imm == BPF_FUNC_map_lookup_elem ||
		     insn->imm == BPF_FUNC_map_update_elem ||
		     insn->imm == BPF_FUNC_map_delete_elem ||
		     insn->imm == BPF_FUNC_map_push_elem   ||
		     insn->imm == BPF_FUNC_map_pop_elem    ||
		     insn->imm == BPF_FUNC_map_peek_elem)) {
			aux = &env->insn_aux_data[i + delta];
			if (bpf_map_ptr_poisoned(aux))
				goto patch_call_imm;

			map_ptr = BPF_MAP_PTR(aux->map_ptr_state);
			ops = map_ptr->ops;
			if (insn->imm == BPF_FUNC_map_lookup_elem &&
			    ops->map_gen_lookup) {
				cnt = ops->map_gen_lookup(map_ptr, insn_buf);
				if (cnt == -EOPNOTSUPP)
					goto patch_map_ops_generic;
				if (cnt <= 0 || cnt >= ARRAY_SIZE(insn_buf)) {
					verbose(env, "bpf verifier is misconfigured\n");
					return -EINVAL;
				}

				new_prog = bpf_patch_insn_data(env, i + delta,
							       insn_buf, cnt);
				if (!new_prog)
					return -ENOMEM;

				delta    += cnt - 1;
				env->prog = prog = new_prog;
				insn      = new_prog->insnsi + i + delta;
				continue;
			}

			BUILD_BUG_ON(!__same_type(ops->map_lookup_elem,
				     (void *(*)(struct bpf_map *map, void *key))NULL));
			BUILD_BUG_ON(!__same_type(ops->map_delete_elem,
				     (int (*)(struct bpf_map *map, void *key))NULL));
			BUILD_BUG_ON(!__same_type(ops->map_update_elem,
				     (int (*)(struct bpf_map *map, void *key, void *value,
					      u64 flags))NULL));
			BUILD_BUG_ON(!__same_type(ops->map_push_elem,
				     (int (*)(struct bpf_map *map, void *value,
					      u64 flags))NULL));
			BUILD_BUG_ON(!__same_type(ops->map_pop_elem,
				     (int (*)(struct bpf_map *map, void *value))NULL));
			BUILD_BUG_ON(!__same_type(ops->map_peek_elem,
				     (int (*)(struct bpf_map *map, void *value))NULL));
patch_map_ops_generic:
			switch (insn->imm) {
			case BPF_FUNC_map_lookup_elem:
				insn->imm = BPF_CAST_CALL(ops->map_lookup_elem) -
					    __bpf_call_base;
				continue;
			case BPF_FUNC_map_update_elem:
				insn->imm = BPF_CAST_CALL(ops->map_update_elem) -
					    __bpf_call_base;
				continue;
			case BPF_FUNC_map_delete_elem:
				insn->imm = BPF_CAST_CALL(ops->map_delete_elem) -
					    __bpf_call_base;
				continue;
			case BPF_FUNC_map_push_elem:
				insn->imm = BPF_CAST_CALL(ops->map_push_elem) -
					    __bpf_call_base;
				continue;
			case BPF_FUNC_map_pop_elem:
				insn->imm = BPF_CAST_CALL(ops->map_pop_elem) -
					    __bpf_call_base;
				continue;
			case BPF_FUNC_map_peek_elem:
				insn->imm = BPF_CAST_CALL(ops->map_peek_elem) -
					    __bpf_call_base;
				continue;
			}

			goto patch_call_imm;
		}

		if (prog->jit_requested && BITS_PER_LONG == 64 &&
		    insn->imm == BPF_FUNC_jiffies64) {
			struct bpf_insn ld_jiffies_addr[2] = {
				BPF_LD_IMM64(BPF_REG_0,
					     (unsigned long)&jiffies),
			};

			insn_buf[0] = ld_jiffies_addr[0];
			insn_buf[1] = ld_jiffies_addr[1];
			insn_buf[2] = BPF_LDX_MEM(BPF_DW, BPF_REG_0,
						  BPF_REG_0, 0);
			cnt = 3;

			new_prog = bpf_patch_insn_data(env, i + delta, insn_buf,
						       cnt);
			if (!new_prog)
				return -ENOMEM;

			delta    += cnt - 1;
			env->prog = prog = new_prog;
			insn      = new_prog->insnsi + i + delta;
			continue;
		}

patch_call_imm:
		fn = env->ops->get_func_proto(insn->imm, env->prog);
		/* all functions that have prototype and verifier allowed
		 * programs to call them, must be real in-kernel functions
		 */
		if (!fn->func) {
			verbose(env,
				"kernel subsystem misconfigured func %s#%d\n",
				func_id_name(insn->imm), insn->imm);
			return -EFAULT;
		}
		insn->imm = fn->func - __bpf_call_base;
	}

	/* Since poke tab is now finalized, publish aux to tracker. */
	for (i = 0; i < prog->aux->size_poke_tab; i++) {
		map_ptr = prog->aux->poke_tab[i].tail_call.map;
		if (!map_ptr->ops->map_poke_track ||
		    !map_ptr->ops->map_poke_untrack ||
		    !map_ptr->ops->map_poke_run) {
			verbose(env, "bpf verifier is misconfigured\n");
			return -EINVAL;
		}

		ret = map_ptr->ops->map_poke_track(map_ptr, prog->aux);
		if (ret < 0) {
			verbose(env, "tracking tail call prog failed\n");
			return ret;
		}
	}

	return 0;
}

Project: linux
File: syscall.c

static const struct bpf_map *bpf_map_from_imm(const struct bpf_prog *prog,
					      unsigned long addr, u32 *off,
					      u32 *type)
{
	const struct bpf_map *map;
	int i;

	mutex_lock(&prog->aux->used_maps_mutex);
	for (i = 0, *off = 0; i < prog->aux->used_map_cnt; i++) {
		map = prog->aux->used_maps[i];
		if (map == (void *)addr) {
			*type = BPF_PSEUDO_MAP_FD;
			goto out;
		}
		if (!map->ops->map_direct_value_meta)
			continue;
		if (!map->ops->map_direct_value_meta(map, addr, off)) {
			*type = BPF_PSEUDO_MAP_VALUE;
			goto out;
		}
	}
	map = NULL;

out:
	mutex_unlock(&prog->aux->used_maps_mutex);
	return map;
}

Project: linux
File: syscall.c

static struct bpf_link *bpf_link_inc_not_zero(struct bpf_link *link)
{
	return atomic64_fetch_add_unless(&link->refcnt, 1, 0) ? link : ERR_PTR(-ENOENT);
}

Project: linux
File: syscall.c

void bpf_prog_sub(struct bpf_prog *prog, int i)
{
	/* Only to be used for undoing previous bpf_prog_add() in some
	 * error path. We still know that another entity in our call
	 * path holds a reference to the program, thus atomic_sub() can
	 * be safely used in such cases!
	 */
	WARN_ON(atomic64_sub_return(i, &prog->aux->refcnt) == 0);
}

Project: linux
File: syscall.c

static ssize_t bpf_dummy_read(struct file *filp, char __user *buf, size_t siz,
			      loff_t *ppos)
{
	/* We need this handler such that alloc_file() enables
	 * f_mode with FMODE_CAN_READ.
	 */
	return -EINVAL;
}

Project: linux
File: syscall.c

void bpf_link_inc(struct bpf_link *link)
{
	atomic64_inc(&link->refcnt);
}