Commit message: maps4: add /proc/pid/pagemap interface

This interface provides a mapping for each page in an address space to its
physical page frame number, allowing precise determination of what pages are
mapped and what pages are shared between processes.

New in this version:

- headers gone again (as recommended by Dave Hansen and Alan Cox)
- 64-bit entries (as per discussion with Andi Kleen)
- swap pte information exported (from Dave Hansen)
- page walker callback for holes (from Dave Hansen)
- direct put_user I/O (as suggested by Rusty Russell)

This patch folds in cleanups and swap PTE support from Dave Hansen
<haveblue@us.ibm.com>.

Signed-off-by: Matt Mackall <mpm@selenic.com>
Cc: Dave Hansen <haveblue@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
CVE: CVE-2016-0823
Vulnerability description: The pagemap_open function in fs/proc/task_mmu.c in the Linux kernel before 3.19.3, as used in Android 6.0.1 before 2016-03-01, allows local users to obtain sensitive physical-address information by reading a pagemap file, aka Android internal bug 25739721.

Project: linux
File: task_mmu.c

static int show_smap(struct seq_file *m, void *v)
{
	struct vm_area_struct *vma = v;
	struct mem_size_stats mss;
	int ret;

	memset(&mss, 0, sizeof mss);
	mss.vma = vma;
	if (vma->vm_mm && !is_vm_hugetlb_page(vma))
		walk_page_range(vma->vm_mm, vma->vm_start, vma->vm_end,
				&smaps_walk, &mss);

	ret = show_map(m, v);
	if (ret)
		return ret;

	seq_printf(m,
		   "Size:           %8lu kB\n"
		   "Rss:            %8lu kB\n"
		   "Pss:            %8lu kB\n"
		   "Shared_Clean:   %8lu kB\n"
		   "Shared_Dirty:   %8lu kB\n"
		   "Private_Clean:  %8lu kB\n"
		   "Private_Dirty:  %8lu kB\n"
		   "Referenced:     %8lu kB\n",
		   (vma->vm_end - vma->vm_start) >> 10,
		   mss.resident >> 10,
		   (unsigned long)(mss.pss >> (10 + PSS_SHIFT)),
		   mss.shared_clean  >> 10,
		   mss.shared_dirty  >> 10,
		   mss.private_clean >> 10,
		   mss.private_dirty >> 10,
		   mss.referenced >> 10);

	return ret;
}

Project: linux
File: base.c

static ssize_t oom_adjust_read(struct file *file, char __user *buf,
				size_t count, loff_t *ppos)
{
	struct task_struct *task = get_proc_task(file->f_path.dentry->d_inode);
	char buffer[PROC_NUMBUF];
	size_t len;
	int oom_adjust;

	if (!task)
		return -ESRCH;
	oom_adjust = task->oomkilladj;
	put_task_struct(task);

	len = snprintf(buffer, sizeof(buffer), "%i\n", oom_adjust);

	return simple_read_from_buffer(buf, count, ppos, buffer, len);
}

Project: linux
File: base.c

static ssize_t proc_fault_inject_write(struct file * file,
			const char __user * buf, size_t count, loff_t *ppos)
{
	struct task_struct *task;
	char buffer[PROC_NUMBUF], *end;
	int make_it_fail;

	if (!capable(CAP_SYS_RESOURCE))
		return -EPERM;
	memset(buffer, 0, sizeof(buffer));
	if (count > sizeof(buffer) - 1)
		count = sizeof(buffer) - 1;
	if (copy_from_user(buffer, buf, count))
		return -EFAULT;
	make_it_fail = simple_strtol(buffer, &end, 0);
	if (*end == '\n')
		end++;
	task = get_proc_task(file->f_dentry->d_inode);
	if (!task)
		return -ESRCH;
	task->make_it_fail = make_it_fail;
	put_task_struct(task);
	if (end - buffer == 0)
		return -EIO;
	return end - buffer;
}

Project: linux
File: base.c

static void *proc_pid_follow_link(struct dentry *dentry, struct nameidata *nd)
{
	struct inode *inode = dentry->d_inode;
	int error = -EACCES;

	/* We don't need a base pointer in the /proc filesystem */
	path_release(nd);

	/* Are we allowed to snoop on the tasks file descriptors? */
	if (!proc_fd_access_allowed(inode))
		goto out;

	error = PROC_I(inode)->op.proc_get_link(inode, &nd->dentry, &nd->mnt);
	nd->last_type = LAST_BIND;
out:
	return ERR_PTR(error);
}

Project: linux
File: base.c

static int proc_self_readlink(struct dentry *dentry, char __user *buffer,
			      int buflen)
{
	char tmp[PROC_NUMBUF];
	sprintf(tmp, "%d", task_tgid_vnr(current));
	return vfs_readlink(dentry,buffer,buflen,tmp);
}

Project: linux
File: base.c

static struct fs_struct *get_fs_struct(struct task_struct *task)
{
	struct fs_struct *fs;
	task_lock(task);
	fs = task->fs;
	if(fs)
		atomic_inc(&fs->count);
	task_unlock(task);
	return fs;
}

Project: linux
File: task_mmu.c

int proc_exe_link(struct inode *inode, struct dentry **dentry, struct vfsmount **mnt)
{
	struct vm_area_struct * vma;
	int result = -ENOENT;
	struct task_struct *task = get_proc_task(inode);
	struct mm_struct * mm = NULL;

	if (task) {
		mm = get_task_mm(task);
		put_task_struct(task);
	}
	if (!mm)
		goto out;
	down_read(&mm->mmap_sem);

	vma = mm->mmap;
	while (vma) {
		if ((vma->vm_flags & VM_EXECUTABLE) && vma->vm_file)
			break;
		vma = vma->vm_next;
	}

	if (vma) {
		*mnt = mntget(vma->vm_file->f_path.mnt);
		*dentry = dget(vma->vm_file->f_path.dentry);
		result = 0;
	}

	up_read(&mm->mmap_sem);
	mmput(mm);
out:
	return result;
}

Project: linux
File: task_mmu.c

static int do_maps_open(struct inode *inode, struct file *file,
			struct seq_operations *ops)
{
	struct proc_maps_private *priv;
	int ret = -ENOMEM;
	priv = kzalloc(sizeof(*priv), GFP_KERNEL);
	if (priv) {
		priv->pid = proc_pid(inode);
		ret = seq_open(file, ops);
		if (!ret) {
			struct seq_file *m = file->private_data;
			m->private = priv;
		} else {
			kfree(priv);
		}
	}
	return ret;
}

Project: linux
File: base.c

static int proc_task_readdir(struct file * filp, void * dirent, filldir_t filldir)
{
	struct dentry *dentry = filp->f_path.dentry;
	struct inode *inode = dentry->d_inode;
	struct task_struct *leader = NULL;
	struct task_struct *task;
	int retval = -ENOENT;
	ino_t ino;
	int tid;
	unsigned long pos = filp->f_pos;  /* avoiding "long long" filp->f_pos */
	struct pid_namespace *ns;

	task = get_proc_task(inode);
	if (!task)
		goto out_no_task;
	rcu_read_lock();
	if (pid_alive(task)) {
		leader = task->group_leader;
		get_task_struct(leader);
	}
	rcu_read_unlock();
	put_task_struct(task);
	if (!leader)
		goto out_no_task;
	retval = 0;

	switch (pos) {
	case 0:
		ino = inode->i_ino;
		if (filldir(dirent, ".", 1, pos, ino, DT_DIR) < 0)
			goto out;
		pos++;
		/* fall through */
	case 1:
		ino = parent_ino(dentry);
		if (filldir(dirent, "..", 2, pos, ino, DT_DIR) < 0)
			goto out;
		pos++;
		/* fall through */
	}

	/* f_version caches the tgid value that the last readdir call couldn't
	 * return. lseek aka telldir automagically resets f_version to 0.
	 */
	ns = filp->f_dentry->d_sb->s_fs_info;
	tid = (int)filp->f_version;
	filp->f_version = 0;
	for (task = first_tid(leader, tid, pos - 2, ns);
	     task;
	     task = next_tid(task), pos++) {
		tid = task_pid_nr_ns(task, ns);
		if (proc_task_fill_cache(filp, dirent, filldir, task, tid) < 0) {
			/* returning this tgid failed, save it as the first
			 * pid for the next readir call */
			filp->f_version = (u64)tid;
			put_task_struct(task);
			break;
		}
	}
out:
	filp->f_pos = pos;
	put_task_struct(leader);
out_no_task:
	return retval;
}

Project: linux
File: base.c

static int proc_cwd_link(struct inode *inode, struct dentry **dentry, struct vfsmount **mnt)
{
	struct task_struct *task = get_proc_task(inode);
	struct fs_struct *fs = NULL;
	int result = -ENOENT;

	if (task) {
		fs = get_fs_struct(task);
		put_task_struct(task);
	}
	if (fs) {
		read_lock(&fs->lock);
		*mnt = mntget(fs->pwdmnt);
		*dentry = dget(fs->pwd);
		read_unlock(&fs->lock);
		result = 0;
		put_fs_struct(fs);
	}
	return result;
}

Project: linux
File: base.c

static ssize_t oom_adjust_write(struct file *file, const char __user *buf,
				size_t count, loff_t *ppos)
{
	struct task_struct *task;
	char buffer[PROC_NUMBUF], *end;
	int oom_adjust;

	memset(buffer, 0, sizeof(buffer));
	if (count > sizeof(buffer) - 1)
		count = sizeof(buffer) - 1;
	if (copy_from_user(buffer, buf, count))
		return -EFAULT;
	oom_adjust = simple_strtol(buffer, &end, 0);
	if ((oom_adjust < OOM_ADJUST_MIN || oom_adjust > OOM_ADJUST_MAX) &&
	     oom_adjust != OOM_DISABLE)
		return -EINVAL;
	if (*end == '\n')
		end++;
	task = get_proc_task(file->f_path.dentry->d_inode);
	if (!task)
		return -ESRCH;
	if (oom_adjust < task->oomkilladj && !capable(CAP_SYS_RESOURCE)) {
		put_task_struct(task);
		return -EACCES;
	}
	task->oomkilladj = oom_adjust;
	put_task_struct(task);
	if (end - buffer == 0)
		return -EIO;
	return end - buffer;
}

Project: linux
File: base.c

static int proc_pid_io_accounting(struct task_struct *task, char *buffer)
{
	return sprintf(buffer,
#ifdef CONFIG_TASK_XACCT
			"rchar: %llu\n"
			"wchar: %llu\n"
			"syscr: %llu\n"
			"syscw: %llu\n"
#endif
			"read_bytes: %llu\n"
			"write_bytes: %llu\n"
			"cancelled_write_bytes: %llu\n",
#ifdef CONFIG_TASK_XACCT
			(unsigned long long)task->rchar,
			(unsigned long long)task->wchar,
			(unsigned long long)task->syscr,
			(unsigned long long)task->syscw,
#endif
			(unsigned long long)task->ioac.read_bytes,
			(unsigned long long)task->ioac.write_bytes,
			(unsigned long long)task->ioac.cancelled_write_bytes);
}

Project: linux
File: base.c

static int proc_oom_score(struct task_struct *task, char *buffer)
{
	unsigned long points;
	struct timespec uptime;

	do_posix_clock_monotonic_gettime(&uptime);
	read_lock(&tasklist_lock);
	points = badness(task, uptime.tv_sec);
	read_unlock(&tasklist_lock);
	return sprintf(buffer, "%lu\n", points);
}

Project: linux
File: base.c

static struct dentry *proc_base_instantiate(struct inode *dir,
	struct dentry *dentry, struct task_struct *task, const void *ptr)
{
	const struct pid_entry *p = ptr;
	struct inode *inode;
	struct proc_inode *ei;
	struct dentry *error = ERR_PTR(-EINVAL);

	/* Allocate the inode */
	error = ERR_PTR(-ENOMEM);
	inode = new_inode(dir->i_sb);
	if (!inode)
		goto out;

	/* Initialize the inode */
	ei = PROC_I(inode);
	inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME;

	/*
	 * grab the reference to the task.
	 */
	ei->pid = get_task_pid(task, PIDTYPE_PID);
	if (!ei->pid)
		goto out_iput;

	inode->i_uid = 0;
	inode->i_gid = 0;
	inode->i_mode = p->mode;
	if (S_ISDIR(inode->i_mode))
		inode->i_nlink = 2;
	if (S_ISLNK(inode->i_mode))
		inode->i_size = 64;
	if (p->iop)
		inode->i_op = p->iop;
	if (p->fop)
		inode->i_fop = p->fop;
	ei->op = p->op;
	dentry->d_op = &proc_base_dentry_operations;
	d_add(dentry, inode);
	error = NULL;
out:
	return error;
out_iput:
	iput(inode);
	goto out;
}

Project: linux
File: base.c

struct mm_struct *mm_for_maps(struct task_struct *task)
{
	struct mm_struct *mm = get_task_mm(task);
	if (!mm)
		return NULL;
	down_read(&mm->mmap_sem);
	task_lock(task);
	if (task->mm != mm)
		goto out;
	if (task->mm != current->mm && __ptrace_may_attach(task) < 0)
		goto out;
	task_unlock(task);
	return mm;
out:
	task_unlock(task);
	up_read(&mm->mmap_sem);
	mmput(mm);
	return NULL;
}

Project: linux
File: base.c

static int proc_pid_wchan(struct task_struct *task, char *buffer)
{
	unsigned long wchan;
	char symname[KSYM_NAME_LEN];

	wchan = get_wchan(task);

	if (lookup_symbol_name(wchan, symname) < 0)
		return sprintf(buffer, "%lu", wchan);
	else
		return sprintf(buffer, "%s", symname);
}

Project: linux
File: task_mmu.c

static int clear_refs_pte_range(pmd_t *pmd, unsigned long addr,
				unsigned long end, void *private)
{
	struct vm_area_struct *vma = private;
	pte_t *pte, ptent;
	spinlock_t *ptl;
	struct page *page;

	pte = pte_offset_map_lock(vma->vm_mm, pmd, addr, &ptl);
	for (; addr != end; pte++, addr += PAGE_SIZE) {
		ptent = *pte;
		if (!pte_present(ptent))
			continue;

		page = vm_normal_page(vma, addr, ptent);
		if (!page)
			continue;

		/* Clear accessed and referenced bits. */
		ptep_test_and_clear_young(vma, addr, pte);
		ClearPageReferenced(page);
	}
	pte_unmap_unlock(pte - 1, ptl);
	cond_resched();
	return 0;
}

Project: linux
File: base.c

static int tid_fd_revalidate(struct dentry *dentry, struct nameidata *nd)
{
	struct inode *inode = dentry->d_inode;
	struct task_struct *task = get_proc_task(inode);
	int fd = proc_fd(inode);
	struct files_struct *files;

	if (task) {
		files = get_files_struct(task);
		if (files) {
			rcu_read_lock();
			if (fcheck_files(files, fd)) {
				rcu_read_unlock();
				put_files_struct(files);
				if (task_dumpable(task)) {
					inode->i_uid = task->euid;
					inode->i_gid = task->egid;
				} else {
					inode->i_uid = 0;
					inode->i_gid = 0;
				}
				inode->i_mode &= ~(S_ISUID | S_ISGID);
				security_task_to_inode(task, inode);
				put_task_struct(task);
				return 1;
			}
			rcu_read_unlock();
			put_files_struct(files);
		}
		put_task_struct(task);
	}
	d_drop(dentry);
	return 0;
}

Project: linux
File: task_mmu.c

static int smaps_pte_range(pmd_t *pmd, unsigned long addr, unsigned long end,
			   void *private)
{
	struct mem_size_stats *mss = private;
	struct vm_area_struct *vma = mss->vma;
	pte_t *pte, ptent;
	spinlock_t *ptl;
	struct page *page;
	int mapcount;

	pte = pte_offset_map_lock(vma->vm_mm, pmd, addr, &ptl);
	for (; addr != end; pte++, addr += PAGE_SIZE) {
		ptent = *pte;
		if (!pte_present(ptent))
			continue;

		mss->resident += PAGE_SIZE;

		page = vm_normal_page(vma, addr, ptent);
		if (!page)
			continue;

		/* Accumulate the size in pages that have been accessed. */
		if (pte_young(ptent) || PageReferenced(page))
			mss->referenced += PAGE_SIZE;
		mapcount = page_mapcount(page);
		if (mapcount >= 2) {
			if (pte_dirty(ptent))
				mss->shared_dirty += PAGE_SIZE;
			else
				mss->shared_clean += PAGE_SIZE;
			mss->pss += (PAGE_SIZE << PSS_SHIFT) / mapcount;
		} else {
			if (pte_dirty(ptent))
				mss->private_dirty += PAGE_SIZE;
			else
				mss->private_clean += PAGE_SIZE;
			mss->pss += (PAGE_SIZE << PSS_SHIFT);
		}
	}
	pte_unmap_unlock(pte - 1, ptl);
	cond_resched();
	return 0;
}

Project: linux
File: base.c

static ssize_t proc_fdinfo_read(struct file *file, char __user *buf,
				      size_t len, loff_t *ppos)
{
	char tmp[PROC_FDINFO_MAX];
	int err = proc_fd_info(file->f_path.dentry->d_inode, NULL, NULL, tmp);
	if (!err)
		err = simple_read_from_buffer(buf, len, ppos, tmp, strlen(tmp));
	return err;
}

Project: linux
File: base.c

static int mounts_open(struct inode *inode, struct file *file)
{
	struct task_struct *task = get_proc_task(inode);
	struct nsproxy *nsp;
	struct mnt_namespace *ns = NULL;
	struct proc_mounts *p;
	int ret = -EINVAL;

	if (task) {
		rcu_read_lock();
		nsp = task_nsproxy(task);
		if (nsp) {
			ns = nsp->mnt_ns;
			if (ns)
				get_mnt_ns(ns);
		}
		rcu_read_unlock();

		put_task_struct(task);
	}

	if (ns) {
		ret = -ENOMEM;
		p = kmalloc(sizeof(struct proc_mounts), GFP_KERNEL);
		if (p) {
			file->private_data = &p->m;
			ret = seq_open(file, &mounts_op);
			if (!ret) {
				p->m.private = ns;
				p->event = ns->event;
				return 0;
			}
			kfree(p);
		}
		put_mnt_ns(ns);
	}
	return ret;
}

Project: linux
File: task_mmu.c

char *task_mem(struct mm_struct *mm, char *buffer)
{
	unsigned long data, text, lib;
	unsigned long hiwater_vm, total_vm, hiwater_rss, total_rss;

	/*
	 * Note: to minimize their overhead, mm maintains hiwater_vm and
	 * hiwater_rss only when about to *lower* total_vm or rss.  Any
	 * collector of these hiwater stats must therefore get total_vm
	 * and rss too, which will usually be the higher.  Barriers? not
	 * worth the effort, such snapshots can always be inconsistent.
	 */
	hiwater_vm = total_vm = mm->total_vm;
	if (hiwater_vm < mm->hiwater_vm)
		hiwater_vm = mm->hiwater_vm;
	hiwater_rss = total_rss = get_mm_rss(mm);
	if (hiwater_rss < mm->hiwater_rss)
		hiwater_rss = mm->hiwater_rss;

	data = mm->total_vm - mm->shared_vm - mm->stack_vm;
	text = (PAGE_ALIGN(mm->end_code) - (mm->start_code & PAGE_MASK)) >> 10;
	lib = (mm->exec_vm << (PAGE_SHIFT-10)) - text;
	buffer += sprintf(buffer,
		"VmPeak:\t%8lu kB\n"
		"VmSize:\t%8lu kB\n"
		"VmLck:\t%8lu kB\n"
		"VmHWM:\t%8lu kB\n"
		"VmRSS:\t%8lu kB\n"
		"VmData:\t%8lu kB\n"
		"VmStk:\t%8lu kB\n"
		"VmExe:\t%8lu kB\n"
		"VmLib:\t%8lu kB\n"
		"VmPTE:\t%8lu kB\n",
		hiwater_vm << (PAGE_SHIFT-10),
		(total_vm - mm->reserved_vm) << (PAGE_SHIFT-10),
		mm->locked_vm << (PAGE_SHIFT-10),
		hiwater_rss << (PAGE_SHIFT-10),
		total_rss << (PAGE_SHIFT-10),
		data << (PAGE_SHIFT-10),
		mm->stack_vm << (PAGE_SHIFT-10), text, lib,
		(PTRS_PER_PTE*sizeof(pte_t)*mm->nr_ptes) >> 10);
	return buffer;
}

Project: linux
File: base.c

static int mounts_release(struct inode *inode, struct file *file)
{
	struct seq_file *m = file->private_data;
	struct mnt_namespace *ns = m->private;
	put_mnt_ns(ns);
	return seq_release(inode, file);
}

Project: linux
File: base.c

static int sched_show(struct seq_file *m, void *v)
{
	struct inode *inode = m->private;
	struct task_struct *p;

	WARN_ON(!inode);

	p = get_proc_task(inode);
	if (!p)
		return -ESRCH;
	proc_sched_show_task(p, m);

	put_task_struct(p);

	return 0;
}

Project: linux
File: base.c

static ssize_t lstats_write(struct file *file, const char __user *buf,
			    size_t count, loff_t *offs)
{
	struct seq_file *m;
	struct task_struct *task;

	m = file->private_data;
	task = m->private;
	clear_all_latency_tracing(task);

	return count;
}

Project: linux
File: base.c

static unsigned mounts_poll(struct file *file, poll_table *wait)
{
	struct proc_mounts *p = file->private_data;
	struct mnt_namespace *ns = p->m.private;
	unsigned res = 0;

	poll_wait(file, &ns->poll, wait);

	spin_lock(&vfsmount_lock);
	if (p->event != ns->event) {
		p->event = ns->event;
		res = POLLERR;
	}
	spin_unlock(&vfsmount_lock);

	return res;
}

Project: linux
File: base.c

static int mountstats_open(struct inode *inode, struct file *file)
{
	int ret = seq_open(file, &mountstats_op);

	if (!ret) {
		struct seq_file *m = file->private_data;
		struct nsproxy *nsp;
		struct mnt_namespace *mnt_ns = NULL;
		struct task_struct *task = get_proc_task(inode);

		if (task) {
			rcu_read_lock();
			nsp = task_nsproxy(task);
			if (nsp) {
				mnt_ns = nsp->mnt_ns;
				if (mnt_ns)
					get_mnt_ns(mnt_ns);
			}
			rcu_read_unlock();

			put_task_struct(task);
		}

		if (mnt_ns)
			m->private = mnt_ns;
		else {
			seq_release(inode, file);
			ret = -EINVAL;
		}
	}
	return ret;
}

Project: linux
File: base.c

static int pid_revalidate(struct dentry *dentry, struct nameidata *nd)
{
	struct inode *inode = dentry->d_inode;
	struct task_struct *task = get_proc_task(inode);
	if (task) {
		if ((inode->i_mode == (S_IFDIR|S_IRUGO|S_IXUGO)) ||
		    task_dumpable(task)) {
			inode->i_uid = task->euid;
			inode->i_gid = task->egid;
		} else {
			inode->i_uid = 0;
			inode->i_gid = 0;
		}
		inode->i_mode &= ~(S_ISUID | S_ISGID);
		security_task_to_inode(task, inode);
		put_task_struct(task);
		return 1;
	}
	d_drop(dentry);
	return 0;
}

Project: linux
File: base.c

static struct inode *proc_pid_make_inode(struct super_block * sb, struct task_struct *task)
{
	struct inode * inode;
	struct proc_inode *ei;

	/* We need a new inode */

	inode = new_inode(sb);
	if (!inode)
		goto out;

	/* Common stuff */
	ei = PROC_I(inode);
	inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME;
	inode->i_op = &proc_def_inode_operations;

	/*
	 * grab the reference to task.
	 */
	ei->pid = get_task_pid(task, PIDTYPE_PID);
	if (!ei->pid)
		goto out_unlock;

	inode->i_uid = 0;
	inode->i_gid = 0;
	if (task_dumpable(task)) {
		inode->i_uid = task->euid;
		inode->i_gid = task->egid;
	}
	security_task_to_inode(task, inode);

out:
	return inode;

out_unlock:
	iput(inode);
	return NULL;
}

Project: linux
File: base.c

static struct dentry *proc_pident_lookup(struct inode *dir, 
					 struct dentry *dentry,
					 const struct pid_entry *ents,
					 unsigned int nents)
{
	struct inode *inode;
	struct dentry *error;
	struct task_struct *task = get_proc_task(dir);
	const struct pid_entry *p, *last;

	error = ERR_PTR(-ENOENT);
	inode = NULL;

	if (!task)
		goto out_no_task;

	/*
	 * Yes, it does not scale. And it should not. Don't add
	 * new entries into /proc/<tgid>/ without very good reasons.
	 */
	last = &ents[nents - 1];
	for (p = ents; p <= last; p++) {
		if (p->len != dentry->d_name.len)
			continue;
		if (!memcmp(dentry->d_name.name, p->name, p->len))
			break;
	}
	if (p > last)
		goto out;

	error = proc_pident_instantiate(dir, dentry, task, p);
out:
	put_task_struct(task);
out_no_task:
	return error;
}

Project: linux
File: base.c

static void *proc_self_follow_link(struct dentry *dentry, struct nameidata *nd)
{
	char tmp[PROC_NUMBUF];
	sprintf(tmp, "%d", task_tgid_vnr(current));
	return ERR_PTR(vfs_follow_link(nd,tmp));
}

Project: linux
File: task_mmu.c

static void *m_start(struct seq_file *m, loff_t *pos)
{
	struct proc_maps_private *priv = m->private;
	unsigned long last_addr = m->version;
	struct mm_struct *mm;
	struct vm_area_struct *vma, *tail_vma = NULL;
	loff_t l = *pos;

	/* Clear the per syscall fields in priv */
	priv->task = NULL;
	priv->tail_vma = NULL;

	/*
	 * We remember last_addr rather than next_addr to hit with
	 * mmap_cache most of the time. We have zero last_addr at
	 * the beginning and also after lseek. We will have -1 last_addr
	 * after the end of the vmas.
	 */

	if (last_addr == -1UL)
		return NULL;

	priv->task = get_pid_task(priv->pid, PIDTYPE_PID);
	if (!priv->task)
		return NULL;

	mm = mm_for_maps(priv->task);
	if (!mm)
		return NULL;

	tail_vma = get_gate_vma(priv->task);
	priv->tail_vma = tail_vma;

	/* Start with last addr hint */
	vma = find_vma(mm, last_addr);
	if (last_addr && vma) {
		vma = vma->vm_next;
		goto out;
	}

	/*
	 * Check the vma index is within the range and do
	 * sequential scan until m_index.
	 */
	vma = NULL;
	if ((unsigned long)l < mm->map_count) {
		vma = mm->mmap;
		while (l-- && vma)
			vma = vma->vm_next;
		goto out;
	}

	if (l != mm->map_count)
		tail_vma = NULL; /* After gate vma */

out:
	if (vma)
		return vma;

	/* End of vmas has been reached */
	m->version = (tail_vma != NULL)? 0: -1UL;
	up_read(&mm->mmap_sem);
	mmput(mm);
	return tail_vma;
}

Project: linux
File: task_mmu.c

int task_statm(struct mm_struct *mm, int *shared, int *text,
	       int *data, int *resident)
{
	*shared = get_mm_counter(mm, file_rss);
	*text = (PAGE_ALIGN(mm->end_code) - (mm->start_code & PAGE_MASK))
								>> PAGE_SHIFT;
	*data = mm->total_vm - mm->shared_vm;
	*resident = *shared + get_mm_counter(mm, anon_rss);
	return mm->total_vm;
}

Project: linux
File: base.c

static int proc_pid_readlink(struct dentry * dentry, char __user * buffer, int buflen)
{
	int error = -EACCES;
	struct inode *inode = dentry->d_inode;
	struct dentry *de;
	struct vfsmount *mnt = NULL;

	/* Are we allowed to snoop on the tasks file descriptors? */
	if (!proc_fd_access_allowed(inode))
		goto out;

	error = PROC_I(inode)->op.proc_get_link(inode, &de, &mnt);
	if (error)
		goto out;

	error = do_proc_readlink(de, mnt, buffer, buflen);
	dput(de);
	mntput(mnt);
out:
	return error;
}

Project: linux
File: base.c

static int lstats_show_proc(struct seq_file *m, void *v)
{
	int i;
	struct task_struct *task = m->private;
	seq_puts(m, "Latency Top version : v0.1\n");

	for (i = 0; i < 32; i++) {
		if (task->latency_record[i].backtrace[0]) {
			int q;
			seq_printf(m, "%i %li %li ",
				task->latency_record[i].count,
				task->latency_record[i].time,
				task->latency_record[i].max);
			for (q = 0; q < LT_BACKTRACEDEPTH; q++) {
				char sym[KSYM_NAME_LEN];
				char *c;
				if (!task->latency_record[i].backtrace[q])
					break;
				if (task->latency_record[i].backtrace[q] == ULONG_MAX)
					break;
				sprint_symbol(sym, task->latency_record[i].backtrace[q]);
				c = strchr(sym, '+');
				if (c)
					*c = 0;
				seq_printf(m, "%s ", sym);
			}
			seq_printf(m, "\n");
		}

	}
	return 0;
}

Project: linux
File: task_mmu.c

static int pagemap_pte_hole(unsigned long start, unsigned long end,
				void *private)
{
	struct pagemapread *pm = private;
	unsigned long addr;
	int err = 0;
	for (addr = start; addr < end; addr += PAGE_SIZE) {
		err = add_to_pagemap(addr, PM_NOT_PRESENT, pm);
		if (err)
			break;
	}
	return err;
}

Project: linux
File: base.c

static struct dentry *proc_fd_instantiate(struct inode *dir,
	struct dentry *dentry, struct task_struct *task, const void *ptr)
{
	unsigned fd = *(const unsigned *)ptr;
	struct file *file;
	struct files_struct *files;
 	struct inode *inode;
 	struct proc_inode *ei;
	struct dentry *error = ERR_PTR(-ENOENT);

	inode = proc_pid_make_inode(dir->i_sb, task);
	if (!inode)
		goto out;
	ei = PROC_I(inode);
	ei->fd = fd;
	files = get_files_struct(task);
	if (!files)
		goto out_iput;
	inode->i_mode = S_IFLNK;

	/*
	 * We are not taking a ref to the file structure, so we must
	 * hold ->file_lock.
	 */
	spin_lock(&files->file_lock);
	file = fcheck_files(files, fd);
	if (!file)
		goto out_unlock;
	if (file->f_mode & 1)
		inode->i_mode |= S_IRUSR | S_IXUSR;
	if (file->f_mode & 2)
		inode->i_mode |= S_IWUSR | S_IXUSR;
	spin_unlock(&files->file_lock);
	put_files_struct(files);

	inode->i_op = &proc_pid_link_inode_operations;
	inode->i_size = 64;
	ei->op.proc_get_link = proc_fd_link;
	dentry->d_op = &tid_fd_dentry_operations;
	d_add(dentry, inode);
	/* Close the race of the process dying before we return the dentry */
	if (tid_fd_revalidate(dentry, NULL))
		error = NULL;

 out:
	return error;
out_unlock:
	spin_unlock(&files->file_lock);
	put_files_struct(files);
out_iput:
	iput(inode);
	goto out;
}

Project: linux
File: task_mmu.c

static ssize_t pagemap_read(struct file *file, char __user *buf,
			    size_t count, loff_t *ppos)
{
	struct task_struct *task = get_proc_task(file->f_path.dentry->d_inode);
	struct page **pages, *page;
	unsigned long uaddr, uend;
	struct mm_struct *mm;
	struct pagemapread pm;
	int pagecount;
	int ret = -ESRCH;

	if (!task)
		goto out;

	ret = -EACCES;
	if (!ptrace_may_attach(task))
		goto out;

	ret = -EINVAL;
	/* file position must be aligned */
	if (*ppos % PM_ENTRY_BYTES)
		goto out;

	ret = 0;
	mm = get_task_mm(task);
	if (!mm)
		goto out;

	ret = -ENOMEM;
	uaddr = (unsigned long)buf & PAGE_MASK;
	uend = (unsigned long)(buf + count);
	pagecount = (PAGE_ALIGN(uend) - uaddr) / PAGE_SIZE;
	pages = kmalloc(pagecount * sizeof(struct page *), GFP_KERNEL);
	if (!pages)
		goto out_task;

	down_read(&current->mm->mmap_sem);
	ret = get_user_pages(current, current->mm, uaddr, pagecount,
			     1, 0, pages, NULL);
	up_read(&current->mm->mmap_sem);

	if (ret < 0)
		goto out_free;

	pm.out = buf;
	pm.end = buf + count;

	if (!ptrace_may_attach(task)) {
		ret = -EIO;
	} else {
		unsigned long src = *ppos;
		unsigned long svpfn = src / PM_ENTRY_BYTES;
		unsigned long start_vaddr = svpfn << PAGE_SHIFT;
		unsigned long end_vaddr = TASK_SIZE_OF(task);

		/* watch out for wraparound */
		if (svpfn > TASK_SIZE_OF(task) >> PAGE_SHIFT)
			start_vaddr = end_vaddr;

		/*
		 * The odds are that this will stop walking way
		 * before end_vaddr, because the length of the
		 * user buffer is tracked in "pm", and the walk
		 * will stop when we hit the end of the buffer.
		 */
		ret = walk_page_range(mm, start_vaddr, end_vaddr,
					&pagemap_walk, &pm);
		if (ret == PM_END_OF_BUFFER)
			ret = 0;
		/* don't need mmap_sem for these, but this looks cleaner */
		*ppos += pm.out - buf;
		if (!ret)
			ret = pm.out - buf;
	}

	for (; pagecount; pagecount--) {
		page = pages[pagecount-1];
		if (!PageReserved(page))
			SetPageDirty(page);
		page_cache_release(page);
	}
	mmput(mm);
out_free:
	kfree(pages);
out_task:
	put_task_struct(task);
out:
	return ret;
}

Project: linux
File: base.c

static int proc_fd_permission(struct inode *inode, int mask,
				struct nameidata *nd)
{
	int rv;

	rv = generic_permission(inode, mask, NULL);
	if (rv == 0)
		return 0;
	if (task_pid(current) == proc_pid(inode))
		rv = 0;
	return rv;
}

Project: linux
File: base.c

static ssize_t environ_read(struct file *file, char __user *buf,
			size_t count, loff_t *ppos)
{
	struct task_struct *task = get_proc_task(file->f_dentry->d_inode);
	char *page;
	unsigned long src = *ppos;
	int ret = -ESRCH;
	struct mm_struct *mm;

	if (!task)
		goto out_no_task;

	if (!ptrace_may_attach(task))
		goto out;

	ret = -ENOMEM;
	page = (char *)__get_free_page(GFP_TEMPORARY);
	if (!page)
		goto out;

	ret = 0;

	mm = get_task_mm(task);
	if (!mm)
		goto out_free;

	while (count > 0) {
		int this_len, retval, max_len;

		this_len = mm->env_end - (mm->env_start + src);

		if (this_len <= 0)
			break;

		max_len = (count > PAGE_SIZE) ? PAGE_SIZE : count;
		this_len = (this_len > max_len) ? max_len : this_len;

		retval = access_process_vm(task, (mm->env_start + src),
			page, this_len, 0);

		if (retval <= 0) {
			ret = retval;
			break;
		}

		if (copy_to_user(buf, page, retval)) {
			ret = -EFAULT;
			break;
		}

		ret += retval;
		src += retval;
		buf += retval;
		count -= retval;
	}
	*ppos = src;

	mmput(mm);
out_free:
	free_page((unsigned long) page);
out:
	put_task_struct(task);
out_no_task:
	return ret;
}

Project: linux
File: base.c

static struct dentry *proc_pid_instantiate(struct inode *dir,
					   struct dentry * dentry,
					   struct task_struct *task, const void *ptr)
{
	struct dentry *error = ERR_PTR(-ENOENT);
	struct inode *inode;

	inode = proc_pid_make_inode(dir->i_sb, task);
	if (!inode)
		goto out;

	inode->i_mode = S_IFDIR|S_IRUGO|S_IXUGO;
	inode->i_op = &proc_tgid_base_inode_operations;
	inode->i_fop = &proc_tgid_base_operations;
	inode->i_flags|=S_IMMUTABLE;
	inode->i_nlink = 5;
#ifdef CONFIG_SECURITY
	inode->i_nlink += 1;
#endif

	dentry->d_op = &pid_dentry_operations;

	d_add(dentry, inode);
	/* Close the race of the process dying before we return the dentry */
	if (pid_revalidate(dentry, NULL))
		error = NULL;
out:
	return error;
}

Project: linux
File: base.c

static int proc_pid_limits(struct task_struct *task, char *buffer)
{
	unsigned int i;
	int count = 0;
	unsigned long flags;
	char *bufptr = buffer;

	struct rlimit rlim[RLIM_NLIMITS];

	rcu_read_lock();
	if (!lock_task_sighand(task,&flags)) {
		rcu_read_unlock();
		return 0;
	}
	memcpy(rlim, task->signal->rlim, sizeof(struct rlimit) * RLIM_NLIMITS);
	unlock_task_sighand(task, &flags);
	rcu_read_unlock();

	/*
	 * print the file header
	 */
	count += sprintf(&bufptr[count], "%-25s %-20s %-20s %-10s\n",
			"Limit", "Soft Limit", "Hard Limit", "Units");

	for (i = 0; i < RLIM_NLIMITS; i++) {
		if (rlim[i].rlim_cur == RLIM_INFINITY)
			count += sprintf(&bufptr[count], "%-25s %-20s ",
					 lnames[i].name, "unlimited");
		else
			count += sprintf(&bufptr[count], "%-25s %-20lu ",
					 lnames[i].name, rlim[i].rlim_cur);

		if (rlim[i].rlim_max == RLIM_INFINITY)
			count += sprintf(&bufptr[count], "%-20s ", "unlimited");
		else
			count += sprintf(&bufptr[count], "%-20lu ",
					 rlim[i].rlim_max);

		if (lnames[i].unit)
			count += sprintf(&bufptr[count], "%-10s\n",
					 lnames[i].unit);
		else
			count += sprintf(&bufptr[count], "\n");
	}

	return count;
}

Project: linux
File: base.c

static int proc_pid_auxv(struct task_struct *task, char *buffer)
{
	int res = 0;
	struct mm_struct *mm = get_task_mm(task);
	if (mm) {
		unsigned int nwords = 0;
		do
			nwords += 2;
		while (mm->saved_auxv[nwords - 2] != 0); /* AT_NULL */
		res = nwords * sizeof(mm->saved_auxv[0]);
		if (res > PAGE_SIZE)
			res = PAGE_SIZE;
		memcpy(buffer, mm->saved_auxv, res);
		mmput(mm);
	}
	return res;
}

Project: linux
File: base.c

static ssize_t mem_read(struct file * file, char __user * buf,
			size_t count, loff_t *ppos)
{
	struct task_struct *task = get_proc_task(file->f_path.dentry->d_inode);
	char *page;
	unsigned long src = *ppos;
	int ret = -ESRCH;
	struct mm_struct *mm;

	if (!task)
		goto out_no_task;

	if (!MAY_PTRACE(task) || !ptrace_may_attach(task))
		goto out;

	ret = -ENOMEM;
	page = (char *)__get_free_page(GFP_TEMPORARY);
	if (!page)
		goto out;

	ret = 0;
 
	mm = get_task_mm(task);
	if (!mm)
		goto out_free;

	ret = -EIO;
 
	if (file->private_data != (void*)((long)current->self_exec_id))
		goto out_put;

	ret = 0;
 
	while (count > 0) {
		int this_len, retval;

		this_len = (count > PAGE_SIZE) ? PAGE_SIZE : count;
		retval = access_process_vm(task, src, page, this_len, 0);
		if (!retval || !MAY_PTRACE(task) || !ptrace_may_attach(task)) {
			if (!ret)
				ret = -EIO;
			break;
		}

		if (copy_to_user(buf, page, retval)) {
			ret = -EFAULT;
			break;
		}
 
		ret += retval;
		src += retval;
		buf += retval;
		count -= retval;
	}
	*ppos = src;

out_put:
	mmput(mm);
out_free:
	free_page((unsigned long) page);
out:
	put_task_struct(task);
out_no_task:
	return ret;
}

Project: linux
File: base.c

static int proc_fd_access_allowed(struct inode *inode)
{
	struct task_struct *task;
	int allowed = 0;
	/* Allow access to a task's file descriptors if it is us or we
	 * may use ptrace attach to the process and find out that
	 * information.
	 */
	task = get_proc_task(inode);
	if (task) {
		allowed = ptrace_may_attach(task);
		put_task_struct(task);
	}
	return allowed;
}

Project: linux
File: base.c

static int proc_root_link(struct inode *inode, struct dentry **dentry, struct vfsmount **mnt)
{
	struct task_struct *task = get_proc_task(inode);
	struct fs_struct *fs = NULL;
	int result = -ENOENT;

	if (task) {
		fs = get_fs_struct(task);
		put_task_struct(task);
	}
	if (fs) {
		read_lock(&fs->lock);
		*mnt = mntget(fs->rootmnt);
		*dentry = dget(fs->root);
		read_unlock(&fs->lock);
		result = 0;
		put_fs_struct(fs);
	}
	return result;
}

Project: linux
File: base.c

static struct dentry *proc_task_instantiate(struct inode *dir,
	struct dentry *dentry, struct task_struct *task, const void *ptr)
{
	struct dentry *error = ERR_PTR(-ENOENT);
	struct inode *inode;
	inode = proc_pid_make_inode(dir->i_sb, task);

	if (!inode)
		goto out;
	inode->i_mode = S_IFDIR|S_IRUGO|S_IXUGO;
	inode->i_op = &proc_tid_base_inode_operations;
	inode->i_fop = &proc_tid_base_operations;
	inode->i_flags|=S_IMMUTABLE;
	inode->i_nlink = 4;
#ifdef CONFIG_SECURITY
	inode->i_nlink += 1;
#endif

	dentry->d_op = &pid_dentry_operations;

	d_add(dentry, inode);
	/* Close the race of the process dying before we return the dentry */
	if (pid_revalidate(dentry, NULL))
		error = NULL;
out:
	return error;
}

Project: linux
File: base.c

static int proc_task_getattr(struct vfsmount *mnt, struct dentry *dentry, struct kstat *stat)
{
	struct inode *inode = dentry->d_inode;
	struct task_struct *p = get_proc_task(inode);
	generic_fillattr(inode, stat);

	if (p) {
		rcu_read_lock();
		stat->nlink += get_nr_threads(p);
		rcu_read_unlock();
		put_task_struct(p);
	}

	return 0;
}

Project: linux
File: base.c

static int proc_fd_link(struct inode *inode, struct dentry **dentry,
			struct vfsmount **mnt)
{
	return proc_fd_info(inode, dentry, mnt, NULL);
}

Project: linux
File: base.c

static ssize_t mem_write(struct file * file, const char __user *buf,
			 size_t count, loff_t *ppos)
{
	int copied;
	char *page;
	struct task_struct *task = get_proc_task(file->f_path.dentry->d_inode);
	unsigned long dst = *ppos;

	copied = -ESRCH;
	if (!task)
		goto out_no_task;

	if (!MAY_PTRACE(task) || !ptrace_may_attach(task))
		goto out;

	copied = -ENOMEM;
	page = (char *)__get_free_page(GFP_TEMPORARY);
	if (!page)
		goto out;

	copied = 0;
	while (count > 0) {
		int this_len, retval;

		this_len = (count > PAGE_SIZE) ? PAGE_SIZE : count;
		if (copy_from_user(page, buf, this_len)) {
			copied = -EFAULT;
			break;
		}
		retval = access_process_vm(task, dst, page, this_len, 1);
		if (!retval) {
			if (!copied)
				copied = -EIO;
			break;
		}
		copied += retval;
		buf += retval;
		dst += retval;
		count -= retval;			
	}
	*ppos = dst;
	free_page((unsigned long) page);
out:
	put_task_struct(task);
out_no_task:
	return copied;
}

Project: linux
File: base.c

static int pid_getattr(struct vfsmount *mnt, struct dentry *dentry, struct kstat *stat)
{
	struct inode *inode = dentry->d_inode;
	struct task_struct *task;
	generic_fillattr(inode, stat);

	rcu_read_lock();
	stat->uid = 0;
	stat->gid = 0;
	task = pid_task(proc_pid(inode), PIDTYPE_PID);
	if (task) {
		if ((inode->i_mode == (S_IFDIR|S_IRUGO|S_IXUGO)) ||
		    task_dumpable(task)) {
			stat->uid = task->euid;
			stat->gid = task->egid;
		}
	}
	rcu_read_unlock();
	return 0;
}

Project: linux
File: task_mmu.c

static int add_to_pagemap(unsigned long addr, u64 pfn,
			  struct pagemapread *pm)
{
	/*
	 * Make sure there's room in the buffer for an
	 * entire entry.  Otherwise, only copy part of
	 * the pfn.
	 */
	if (pm->out + PM_ENTRY_BYTES >= pm->end) {
		if (copy_to_user(pm->out, &pfn, pm->end - pm->out))
			return -EFAULT;
		pm->out = pm->end;
		return PM_END_OF_BUFFER;
	}

	if (put_user(pfn, pm->out))
		return -EFAULT;
	pm->out += PM_ENTRY_BYTES;
	return 0;
}

Project: linux
File: base.c

static int proc_readfd_common(struct file * filp, void * dirent,
			      filldir_t filldir, instantiate_t instantiate)
{
	struct dentry *dentry = filp->f_path.dentry;
	struct inode *inode = dentry->d_inode;
	struct task_struct *p = get_proc_task(inode);
	unsigned int fd, ino;
	int retval;
	struct files_struct * files;
	struct fdtable *fdt;

	retval = -ENOENT;
	if (!p)
		goto out_no_task;
	retval = 0;

	fd = filp->f_pos;
	switch (fd) {
		case 0:
			if (filldir(dirent, ".", 1, 0, inode->i_ino, DT_DIR) < 0)
				goto out;
			filp->f_pos++;
		case 1:
			ino = parent_ino(dentry);
			if (filldir(dirent, "..", 2, 1, ino, DT_DIR) < 0)
				goto out;
			filp->f_pos++;
		default:
			files = get_files_struct(p);
			if (!files)
				goto out;
			rcu_read_lock();
			fdt = files_fdtable(files);
			for (fd = filp->f_pos-2;
			     fd < fdt->max_fds;
			     fd++, filp->f_pos++) {
				char name[PROC_NUMBUF];
				int len;

				if (!fcheck_files(files, fd))
					continue;
				rcu_read_unlock();

				len = snprintf(name, sizeof(name), "%d", fd);
				if (proc_fill_cache(filp, dirent, filldir,
						    name, len, instantiate,
						    p, &fd) < 0) {
					rcu_read_lock();
					break;
				}
				rcu_read_lock();
			}
			rcu_read_unlock();
			put_files_struct(files);
	}
out:
	put_task_struct(p);
out_no_task:
	return retval;
}

Project: linux
File: base.c

static ssize_t proc_pid_attr_write(struct file * file, const char __user * buf,
				   size_t count, loff_t *ppos)
{
	struct inode * inode = file->f_path.dentry->d_inode;
	char *page;
	ssize_t length;
	struct task_struct *task = get_proc_task(inode);

	length = -ESRCH;
	if (!task)
		goto out_no_task;
	if (count > PAGE_SIZE)
		count = PAGE_SIZE;

	/* No partial writes. */
	length = -EINVAL;
	if (*ppos != 0)
		goto out;

	length = -ENOMEM;
	page = (char*)__get_free_page(GFP_TEMPORARY);
	if (!page)
		goto out;

	length = -EFAULT;
	if (copy_from_user(page, buf, count))
		goto out_free;

	length = security_setprocattr(task,
				      (char*)file->f_path.dentry->d_name.name,
				      (void*)page, count);
out_free:
	free_page((unsigned long) page);
out:
	put_task_struct(task);
out_no_task:
	return length;
}

Project: linux
File: base.c

static void proc_flush_task_mnt(struct vfsmount *mnt, pid_t pid, pid_t tgid)
{
	struct dentry *dentry, *leader, *dir;
	char buf[PROC_NUMBUF];
	struct qstr name;

	name.name = buf;
	name.len = snprintf(buf, sizeof(buf), "%d", pid);
	dentry = d_hash_and_lookup(mnt->mnt_root, &name);
	if (dentry) {
		shrink_dcache_parent(dentry);
		d_drop(dentry);
		dput(dentry);
	}

	if (tgid == 0)
		goto out;

	name.name = buf;
	name.len = snprintf(buf, sizeof(buf), "%d", tgid);
	leader = d_hash_and_lookup(mnt->mnt_root, &name);
	if (!leader)
		goto out;

	name.name = "task";
	name.len = strlen(name.name);
	dir = d_hash_and_lookup(leader, &name);
	if (!dir)
		goto out_put_leader;

	name.name = buf;
	name.len = snprintf(buf, sizeof(buf), "%d", pid);
	dentry = d_hash_and_lookup(dir, &name);
	if (dentry) {
		shrink_dcache_parent(dentry);
		d_drop(dentry);
		dput(dentry);
	}

	dput(dir);
out_put_leader:
	dput(leader);
out:
	return;
}

Project: linux
File: base.c

static int lstats_open(struct inode *inode, struct file *file)
{
	int ret;
	struct seq_file *m;
	struct task_struct *task = get_proc_task(inode);

	ret = single_open(file, lstats_show_proc, NULL);
	if (!ret) {
		m = file->private_data;
		m->private = task;
	}
	return ret;
}

Project: linux
File: task_mmu.c

static ssize_t clear_refs_write(struct file *file, const char __user *buf,
				size_t count, loff_t *ppos)
{
	struct task_struct *task;
	char buffer[PROC_NUMBUF], *end;
	struct mm_struct *mm;
	struct vm_area_struct *vma;

	memset(buffer, 0, sizeof(buffer));
	if (count > sizeof(buffer) - 1)
		count = sizeof(buffer) - 1;
	if (copy_from_user(buffer, buf, count))
		return -EFAULT;
	if (!simple_strtol(buffer, &end, 0))
		return -EINVAL;
	if (*end == '\n')
		end++;
	task = get_proc_task(file->f_path.dentry->d_inode);
	if (!task)
		return -ESRCH;
	mm = get_task_mm(task);
	if (mm) {
		down_read(&mm->mmap_sem);
		for (vma = mm->mmap; vma; vma = vma->vm_next)
			if (!is_vm_hugetlb_page(vma))
				walk_page_range(mm, vma->vm_start, vma->vm_end,
						&clear_refs_walk, vma);
		flush_tlb_mm(mm);
		up_read(&mm->mmap_sem);
		mmput(mm);
	}
	put_task_struct(task);
	if (end - buffer == 0)
		return -EIO;
	return end - buffer;
}

Project: linux
File: task_mmu.c

static void *m_next(struct seq_file *m, void *v, loff_t *pos)
{
	struct proc_maps_private *priv = m->private;
	struct vm_area_struct *vma = v;
	struct vm_area_struct *tail_vma = priv->tail_vma;

	(*pos)++;
	if (vma && (vma != tail_vma) && vma->vm_next)
		return vma->vm_next;
	vma_stop(priv, vma);
	return (vma != tail_vma)? tail_vma: NULL;
}

Project: linux
File: task_mmu.c

u64 swap_pte_to_pagemap_entry(pte_t pte)
{
	swp_entry_t e = pte_to_swp_entry(pte);
	return PM_SWAP | swp_type(e) | (swp_offset(e) << MAX_SWAPFILES_SHIFT);
}

Project: linux
File: base.c

void proc_flush_task(struct task_struct *task)
{
	int i;
	struct pid *pid, *tgid = NULL;
	struct upid *upid;

	pid = task_pid(task);
	if (thread_group_leader(task))
		tgid = task_tgid(task);

	for (i = 0; i <= pid->level; i++) {
		upid = &pid->numbers[i];
		proc_flush_task_mnt(upid->ns->proc_mnt, upid->nr,
			tgid ? tgid->numbers[i].nr : 0);
	}

	upid = &pid->numbers[pid->level];
	if (upid->nr == 1)
		pid_ns_release_proc(upid->ns);
}

Project: linux
File: base.c

static int proc_pid_schedstat(struct task_struct *task, char *buffer)
{
	return sprintf(buffer, "%llu %llu %lu\n",
			task->sched_info.cpu_time,
			task->sched_info.run_delay,
			task->sched_info.pcount);
}

Project: linux
File: base.c

sched_write(struct file *file, const char __user *buf,
	    size_t count, loff_t *offset)
{
	struct inode *inode = file->f_path.dentry->d_inode;
	struct task_struct *p;

	WARN_ON(!inode);

	p = get_proc_task(inode);
	if (!p)
		return -ESRCH;
	proc_sched_set_task(p);

	put_task_struct(p);

	return count;
}

Project: linux
File: base.c

static int get_nr_threads(struct task_struct *tsk)
{
	/* Must be called with the rcu_read_lock held */
	unsigned long flags;
	int count = 0;

	if (lock_task_sighand(tsk, &flags)) {
		count = atomic_read(&tsk->signal->count);
		unlock_task_sighand(tsk, &flags);
	}
	return count;
}

Project: linux
File: task_mmu.c

static int pagemap_pte_range(pmd_t *pmd, unsigned long addr, unsigned long end,
			     void *private)
{
	struct pagemapread *pm = private;
	pte_t *pte;
	int err = 0;

	for (; addr != end; addr += PAGE_SIZE) {
		u64 pfn = PM_NOT_PRESENT;
		pte = pte_offset_map(pmd, addr);
		if (is_swap_pte(*pte))
			pfn = swap_pte_to_pagemap_entry(*pte);
		else if (pte_present(*pte))
			pfn = pte_pfn(*pte);
		/* unmap so we're not in atomic when we copy to userspace */
		pte_unmap(pte);
		err = add_to_pagemap(addr, pfn, pm);
		if (err)
			return err;
	}

	cond_resched();

	return err;
}

Project: linux
File: base.c

static struct dentry *proc_pident_instantiate(struct inode *dir,
	struct dentry *dentry, struct task_struct *task, const void *ptr)
{
	const struct pid_entry *p = ptr;
	struct inode *inode;
	struct proc_inode *ei;
	struct dentry *error = ERR_PTR(-EINVAL);

	inode = proc_pid_make_inode(dir->i_sb, task);
	if (!inode)
		goto out;

	ei = PROC_I(inode);
	inode->i_mode = p->mode;
	if (S_ISDIR(inode->i_mode))
		inode->i_nlink = 2;	/* Use getattr to fix if necessary */
	if (p->iop)
		inode->i_op = p->iop;
	if (p->fop)
		inode->i_fop = p->fop;
	ei->op = p->op;
	dentry->d_op = &pid_dentry_operations;
	d_add(dentry, inode);
	/* Close the race of the process dying before we return the dentry */
	if (pid_revalidate(dentry, NULL))
		error = NULL;
out:
	return error;
}

Project: linux
File: task_mmu.c

static void vma_stop(struct proc_maps_private *priv, struct vm_area_struct *vma)
{
	if (vma && vma != priv->tail_vma) {
		struct mm_struct *mm = vma->vm_mm;
		up_read(&mm->mmap_sem);
		mmput(mm);
	}
}

Project: linux
File: task_mmu.c

static int smaps_open(struct inode *inode, struct file *file)
{
	return do_maps_open(inode, file, &proc_pid_smaps_op);
}

Project: linux
File: task_mmu.c

unsigned long task_vsize(struct mm_struct *mm)
{
	return PAGE_SIZE * mm->total_vm;
}

Project: linux
File: base.c

static int proc_fd_info(struct inode *inode, struct dentry **dentry,
			struct vfsmount **mnt, char *info)
{
	struct task_struct *task = get_proc_task(inode);
	struct files_struct *files = NULL;
	struct file *file;
	int fd = proc_fd(inode);

	if (task) {
		files = get_files_struct(task);
		put_task_struct(task);
	}
	if (files) {
		/*
		 * We are not taking a ref to the file structure, so we must
		 * hold ->file_lock.
		 */
		spin_lock(&files->file_lock);
		file = fcheck_files(files, fd);
		if (file) {
			if (mnt)
				*mnt = mntget(file->f_path.mnt);
			if (dentry)
				*dentry = dget(file->f_path.dentry);
			if (info)
				snprintf(info, PROC_FDINFO_MAX,
					 "pos:\t%lli\n"
					 "flags:\t0%o\n",
					 (long long) file->f_pos,
					 file->f_flags);
			spin_unlock(&files->file_lock);
			put_files_struct(files);
			return 0;
		}
		spin_unlock(&files->file_lock);
		put_files_struct(files);
	}
	return -ENOENT;
}

Project: linux
File: task_mmu.c

static int show_numa_map_checked(struct seq_file *m, void *v)
{
	struct proc_maps_private *priv = m->private;
	struct task_struct *task = priv->task;

	if (maps_protect && !ptrace_may_attach(task))
		return -EACCES;

	return show_numa_map(m, v);
}

Project: linux
File: base.c

static int do_proc_readlink(struct dentry *dentry, struct vfsmount *mnt,
			    char __user *buffer, int buflen)
{
	struct inode * inode;
	char *tmp = (char*)__get_free_page(GFP_TEMPORARY);
	char *path;
	int len;

	if (!tmp)
		return -ENOMEM;

	inode = dentry->d_inode;
	path = d_path(dentry, mnt, tmp, PAGE_SIZE);
	len = PTR_ERR(path);
	if (IS_ERR(path))
		goto out;
	len = tmp + PAGE_SIZE - 1 - path;

	if (len > buflen)
		len = buflen;
	if (copy_to_user(buffer, path, len))
		len = -EFAULT;
 out:
	free_page((unsigned long)tmp);
	return len;
}

Project: linux
File: task_mmu.c

static int maps_open(struct inode *inode, struct file *file)
{
	return do_maps_open(inode, file, &proc_pid_maps_op);
}

Project: linux
File: task_mmu.c

static void pad_len_spaces(struct seq_file *m, int len)
{
	len = 25 + sizeof(void*) * 6 - len;
	if (len < 1)
		len = 1;
	seq_printf(m, "%*c", len, ' ');
}

Project: linux
File: task_mmu.c

static int show_map(struct seq_file *m, void *v)
{
	struct proc_maps_private *priv = m->private;
	struct task_struct *task = priv->task;
	struct vm_area_struct *vma = v;
	struct mm_struct *mm = vma->vm_mm;
	struct file *file = vma->vm_file;
	int flags = vma->vm_flags;
	unsigned long ino = 0;
	dev_t dev = 0;
	int len;

	if (maps_protect && !ptrace_may_attach(task))
		return -EACCES;

	if (file) {
		struct inode *inode = vma->vm_file->f_path.dentry->d_inode;
		dev = inode->i_sb->s_dev;
		ino = inode->i_ino;
	}

	seq_printf(m, "%08lx-%08lx %c%c%c%c %08lx %02x:%02x %lu %n",
			vma->vm_start,
			vma->vm_end,
			flags & VM_READ ? 'r' : '-',
			flags & VM_WRITE ? 'w' : '-',
			flags & VM_EXEC ? 'x' : '-',
			flags & VM_MAYSHARE ? 's' : 'p',
			vma->vm_pgoff << PAGE_SHIFT,
			MAJOR(dev), MINOR(dev), ino, &len);

	/*
	 * Print the dentry name for named mappings, and a
	 * special [heap] marker for the heap:
	 */
	if (file) {
		pad_len_spaces(m, len);
		seq_path(m, file->f_path.mnt, file->f_path.dentry, "\n");
	} else {
		const char *name = arch_vma_name(vma);
		if (!name) {
			if (mm) {
				if (vma->vm_start <= mm->start_brk &&
						vma->vm_end >= mm->brk) {
					name = "[heap]";
				} else if (vma->vm_start <= mm->start_stack &&
					   vma->vm_end >= mm->start_stack) {
					name = "[stack]";
				}
			} else {
				name = "[vdso]";
			}
		}
		if (name) {
			pad_len_spaces(m, len);
			seq_puts(m, name);
		}
	}
	seq_putc(m, '\n');

	if (m->count < m->size)  /* vma is copied successfully */
		m->version = (vma != get_gate_vma(task))? vma->vm_start: 0;
	return 0;
}