Kernel bug: possible deadlock in ocfs2_reserve_local_alloc_bits
Subsystem: ocfs2
Status: open

Crash report:
JBD2: Ignoring recovery information on journal
ocfs2: Mounting device (7,0) on (node local, slot 0) with ordered data mode.
overlayfs: upper fs does not support tmpfile.
overlayfs: upper fs does not support RENAME_WHITEOUT.
======================================================
WARNING: possible circular locking dependency detected
syzkaller #0 Not tainted
-------------------------[  127.360921][ T6061] ------------------------------------------------------
syz.0.17/6061 is trying to acquire lock:
ffff8880437e3dc0 (&ocfs2_sysfile_lock_key[LOCAL_ALLOC_SYSTEM_INODE]){+.+.}-{4:4}, at: inode_lock include/linux/fs.h:1027 [inline]
ffff8880437e3dc0 (&ocfs2_sysfile_lock_key[LOCAL_ALLOC_SYSTEM_INODE]){+.+.}-{4:4}, at: ocfs2_reserve_local_alloc_bits+0x125/0x24b0 fs/ocfs2/localalloc.c:636

but task is already holding lock:
ffff888043613a98 (&oi->ip_xattr_sem){+.+.}-{4:4}, at: ocfs2_xattr_set+0x40f/0x11f0 fs/ocfs2/xattr.c:3613

which lock already depends on the new lock.


the existing dependency chain (in reverse order) is:

-> #3 (&oi->ip_xattr_sem){+.+.}-{4:4}:
       down_write+0x3a/0x50 kernel/locking/rwsem.c:1590
       ocfs2_xattr_set_handle+0x3b0/0x7a0 fs/ocfs2/xattr.c:3531
       ocfs2_init_security_set+0xbd/0xe0 fs/ocfs2/xattr.c:7337
       ocfs2_mknod+0x135d/0x2030 fs/ocfs2/namei.c:423
       ocfs2_mkdir+0x181/0x420 fs/ocfs2/namei.c:660
       vfs_mkdir+0x52d/0x5d0 fs/namei.c:5130
       do_mkdirat+0x27a/0x4b0 fs/namei.c:5164
       __do_sys_mkdirat fs/namei.c:5186 [inline]
       __se_sys_mkdirat fs/namei.c:5184 [inline]
       __x64_sys_mkdirat+0x87/0xa0 fs/namei.c:5184
       do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
       do_syscall_64+0xfa/0xf80 arch/x86/entry/syscall_64.c:94
       entry_SYSCALL_64_after_hwframe+0x77/0x7f

-> #2 (&journal->j_trans_barrier){.+.+}-{4:4}:
       down_read+0x97/0x1f0 kernel/locking/rwsem.c:1537
       ocfs2_start_trans+0x36b/0x6d0 fs/ocfs2/journal.c:372
       ocfs2_block_group_alloc fs/ocfs2/suballoc.c:686 [inline]
       ocfs2_reserve_suballoc_bits+0x722/0x4600 fs/ocfs2/suballoc.c:835
       ocfs2_reserve_new_metadata_blocks+0x403/0x940 fs/ocfs2/suballoc.c:985
       ocfs2_mknod+0xde6/0x2030 fs/ocfs2/namei.c:351
       ocfs2_mkdir+0x181/0x420 fs/ocfs2/namei.c:660
       vfs_mkdir+0x52d/0x5d0 fs/namei.c:5130
       do_mkdirat+0x27a/0x4b0 fs/namei.c:5164
       __do_sys_mkdirat fs/namei.c:5186 [inline]
       __se_sys_mkdirat fs/namei.c:5184 [inline]
       __x64_sys_mkdirat+0x87/0xa0 fs/namei.c:5184
       do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
       do_syscall_64+0xfa/0xf80 arch/x86/entry/syscall_64.c:94
       entry_SYSCALL_64_after_hwframe+0x77/0x7f

-> #1 (sb_internal#2){.+.+}-{0:0}:
       percpu_down_read_internal include/linux/percpu-rwsem.h:53 [inline]
       percpu_down_read_freezable include/linux/percpu-rwsem.h:83 [inline]
       __sb_start_write include/linux/fs/super.h:19 [inline]
       sb_start_intwrite include/linux/fs/super.h:177 [inline]
       ocfs2_start_trans+0x26b/0x6d0 fs/ocfs2/journal.c:370
       ocfs2_mknod+0xe71/0x2030 fs/ocfs2/namei.c:365
       ocfs2_mkdir+0x181/0x420 fs/ocfs2/namei.c:660
       vfs_mkdir+0x52d/0x5d0 fs/namei.c:5130
       do_mkdirat+0x27a/0x4b0 fs/namei.c:5164
       __do_sys_mkdirat fs/namei.c:5186 [inline]
       __se_sys_mkdirat fs/namei.c:5184 [inline]
       __x64_sys_mkdirat+0x87/0xa0 fs/namei.c:5184
       do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
       do_syscall_64+0xfa/0xf80 arch/x86/entry/syscall_64.c:94
       entry_SYSCALL_64_after_hwframe+0x77/0x7f

-> #0 (&ocfs2_sysfile_lock_key[LOCAL_ALLOC_SYSTEM_INODE]){+.+.}-{4:4}:
       check_prev_add kernel/locking/lockdep.c:3165 [inline]
       check_prevs_add kernel/locking/lockdep.c:3284 [inline]
       validate_chain kernel/locking/lockdep.c:3908 [inline]
       __lock_acquire+0x15a6/0x2cf0 kernel/locking/lockdep.c:5237
       lock_acquire+0x117/0x340 kernel/locking/lockdep.c:5868
       down_write+0x3a/0x50 kernel/locking/rwsem.c:1590
       inode_lock include/linux/fs.h:1027 [inline]
       ocfs2_reserve_local_alloc_bits+0x125/0x24b0 fs/ocfs2/localalloc.c:636
       ocfs2_reserve_clusters_with_limit+0x1be/0xba0 fs/ocfs2/suballoc.c:1169
       ocfs2_init_xattr_set_ctxt+0x366/0x6e0 fs/ocfs2/xattr.c:3316
       ocfs2_xattr_set+0xb70/0x11f0 fs/ocfs2/xattr.c:3664
       __vfs_setxattr+0x43c/0x480 fs/xattr.c:200
       __vfs_setxattr_noperm+0x12d/0x660 fs/xattr.c:234
       vfs_setxattr+0x16b/0x2f0 fs/xattr.c:321
       ovl_do_setxattr fs/overlayfs/overlayfs.h:317 [inline]
       ovl_setxattr fs/overlayfs/overlayfs.h:329 [inline]
       ovl_make_workdir fs/overlayfs/super.c:728 [inline]
       ovl_get_workdir fs/overlayfs/super.c:840 [inline]
       ovl_fill_super_creds fs/overlayfs/super.c:1453 [inline]
       ovl_fill_super+0x4781/0x5a90 fs/overlayfs/super.c:1567
       vfs_get_super fs/super.c:1324 [inline]
       get_tree_nodev+0xbb/0x150 fs/super.c:1343
       vfs_get_tree+0x92/0x2a0 fs/super.c:1751
       fc_mount fs/namespace.c:1199 [inline]
       do_new_mount_fc fs/namespace.c:3636 [inline]
       do_new_mount+0x302/0xa10 fs/namespace.c:3712
       do_mount fs/namespace.c:4035 [inline]
       __do_sys_mount fs/namespace.c:4224 [inline]
       __se_sys_mount+0x313/0x410 fs/namespace.c:4201
       do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
       do_syscall_64+0xfa/0xf80 arch/x86/entry/syscall_64.c:94
       entry_SYSCALL_64_after_hwframe+0x77/0x7f

other info that might help us debug this:

Chain exists of:
  &ocfs2_sysfile_lock_key[LOCAL_ALLOC_SYSTEM_INODE] --> &journal->j_trans_barrier --> &oi->ip_xattr_sem

 Possible unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  lock(&oi->ip_xattr_sem);
                               lock(&journal->j_trans_barrier);
                               lock(&oi->ip_xattr_sem);
  lock(&ocfs2_sysfile_lock_key[LOCAL_ALLOC_SYSTEM_INODE]);

 *** DEADLOCK ***

4 locks held by syz.0.17/6061:
 #0: ffff8880555bc0d0 (&type->s_umount_key#55/1){+.+.}-{4:4}, at: alloc_super+0x28c/0xab0 fs/super.c:344
 #1: ffff888037c5c480 (sb_writers#12){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:499
 #2: ffff888043613dc0 (&sb->s_type->i_mutex_key#25){++++}-{4:4}, at: inode_lock include/linux/fs.h:1027 [inline]
 #2: ffff888043613dc0 (&sb->s_type->i_mutex_key#25){++++}-{4:4}, at: vfs_setxattr+0x144/0x2f0 fs/xattr.c:320
 #3: ffff888043613a98 (&oi->ip_xattr_sem){+.+.}-{4:4}, at: ocfs2_xattr_set+0x40f/0x11f0 fs/ocfs2/xattr.c:3613

stack backtrace:
CPU: 1 UID: 0 PID: 6061 Comm: syz.0.17 Not tainted syzkaller #0 PREEMPT_{RT,(full)} 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
Call Trace:
 <TASK>
 dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120
 print_circular_bug+0x2e2/0x300 kernel/locking/lockdep.c:2043
 check_noncircular+0x12e/0x150 kernel/locking/lockdep.c:2175
 check_prev_add kernel/locking/lockdep.c:3165 [inline]
 check_prevs_add kernel/locking/lockdep.c:3284 [inline]
 validate_chain kernel/locking/lockdep.c:3908 [inline]
 __lock_acquire+0x15a6/0x2cf0 kernel/locking/lockdep.c:5237
 lock_acquire+0x117/0x340 kernel/locking/lockdep.c:5868
 down_write+0x3a/0x50 kernel/locking/rwsem.c:1590
 inode_lock include/linux/fs.h:1027 [inline]
 ocfs2_reserve_local_alloc_bits+0x125/0x24b0 fs/ocfs2/localalloc.c:636
 ocfs2_reserve_clusters_with_limit+0x1be/0xba0 fs/ocfs2/suballoc.c:1169
 ocfs2_init_xattr_set_ctxt+0x366/0x6e0 fs/ocfs2/xattr.c:3316
 ocfs2_xattr_set+0xb70/0x11f0 fs/ocfs2/xattr.c:3664
 __vfs_setxattr+0x43c/0x480 fs/xattr.c:200
 __vfs_setxattr_noperm+0x12d/0x660 fs/xattr.c:234
 vfs_setxattr+0x16b/0x2f0 fs/xattr.c:321
 ovl_do_setxattr fs/overlayfs/overlayfs.h:317 [inline]
 ovl_setxattr fs/overlayfs/overlayfs.h:329 [inline]
 ovl_make_workdir fs/overlayfs/super.c:728 [inline]
 ovl_get_workdir fs/overlayfs/super.c:840 [inline]
 ovl_fill_super_creds fs/overlayfs/super.c:1453 [inline]
 ovl_fill_super+0x4781/0x5a90 fs/overlayfs/super.c:1567
 vfs_get_super fs/super.c:1324 [inline]
 get_tree_nodev+0xbb/0x150 fs/super.c:1343
 vfs_get_tree+0x92/0x2a0 fs/super.c:1751
 fc_mount fs/namespace.c:1199 [inline]
 do_new_mount_fc fs/namespace.c:3636 [inline]
 do_new_mount+0x302/0xa10 fs/namespace.c:3712
 do_mount fs/namespace.c:4035 [inline]
 __do_sys_mount fs/namespace.c:4224 [inline]
 __se_sys_mount+0x313/0x410 fs/namespace.c:4201
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xfa/0xf80 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f11cac2f749
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fff17458b68 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00007f11cae85fa0 RCX: 00007f11cac2f749
RDX: 0000200000000b80 RSI: 0000200000000100 RDI: 0000000000000000
RBP: 00007f11cacb3f91 R08: 0000200000000180 R09: 0000000000000000
R10: 0000000000000008 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f11cae85fa0 R14: 00007f11cae85fa0 R15: 0000000000000005
 </TASK>
------------[ cut here ]------------
UBSAN: array-index-out-of-bounds in fs/ocfs2/xattr.c:1985:3
index 2 is out of range for type 'struct ocfs2_xattr_entry[] __counted_by(xh_count)' (aka 'struct ocfs2_xattr_entry[]')
CPU: 1 UID: 0 PID: 6061 Comm: syz.0.17 Not tainted syzkaller #0 PREEMPT_{RT,(full)} 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
Call Trace:
 <TASK>
 dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120
 ubsan_epilogue+0xa/0x40 lib/ubsan.c:233
 __ubsan_handle_out_of_bounds+0xe9/0xf0 lib/ubsan.c:455
 ocfs2_xa_remove_entry+0x36d/0x3e0 fs/ocfs2/xattr.c:1985
 ocfs2_xa_remove fs/ocfs2/xattr.c:2073 [inline]
 ocfs2_xa_set+0xaf4/0x2a70 fs/ocfs2/xattr.c:2277
 ocfs2_xattr_block_set+0x3ca/0x31b0 fs/ocfs2/xattr.c:3015
 __ocfs2_xattr_set_handle+0x27e/0xf20 fs/ocfs2/xattr.c:-1
 ocfs2_xattr_set+0xde8/0x11f0 fs/ocfs2/xattr.c:3680
 __vfs_removexattr+0x431/0x470 fs/xattr.c:518
 __vfs_removexattr_locked+0x1ee/0x230 fs/xattr.c:553
 vfs_removexattr+0x80/0x1b0 fs/xattr.c:575
 ovl_do_removexattr fs/overlayfs/overlayfs.h:335 [inline]
 ovl_removexattr fs/overlayfs/overlayfs.h:343 [inline]
 ovl_make_workdir fs/overlayfs/super.c:760 [inline]
 ovl_get_workdir fs/overlayfs/super.c:840 [inline]
 ovl_fill_super_creds fs/overlayfs/super.c:1453 [inline]
 ovl_fill_super+0x487b/0x5a90 fs/overlayfs/super.c:1567
 vfs_get_super fs/super.c:1324 [inline]
 get_tree_nodev+0xbb/0x150 fs/super.c:1343
 vfs_get_tree+0x92/0x2a0 fs/super.c:1751
 fc_mount fs/namespace.c:1199 [inline]
 do_new_mount_fc fs/namespace.c:3636 [inline]
 do_new_mount+0x302/0xa10 fs/namespace.c:3712
 do_mount fs/namespace.c:4035 [inline]
 __do_sys_mount fs/namespace.c:4224 [inline]
 __se_sys_mount+0x313/0x410 fs/namespace.c:4201
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xfa/0xf80 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f11cac2f749
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fff17458b68 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00007f11cae85fa0 RCX: 00007f11cac2f749
RDX: 0000200000000b80 RSI: 0000200000000100 RDI: 0000000000000000
RBP: 00007f11cacb3f91 R08: 0000200000000180 R09: 0000000000000000
R10: 0000000000000008 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f11cae85fa0 R14: 00007f11cae85fa0 R15: 0000000000000005
 </TASK>
---[ end trace ]---