syzbot


possible deadlock in ocfs2_lock_global_qf (2)

Status: upstream: reported on 2026/02/22 05:28
Reported-by: syzbot+8e3565cd6ea0945c6d7a@syzkaller.appspotmail.com
First crash: 61d, last: 1d05h
Similar bugs (5)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-6.1 possible deadlock in ocfs2_lock_global_qf (2) 4 1 21d 21d 0/3 upstream: reported on 2026/04/03 07:37
linux-6.6 possible deadlock in ocfs2_lock_global_qf 4 1 273d 273d 0/2 auto-obsoleted due to no activity on 2025/11/01 13:37
upstream possible deadlock in ocfs2_lock_global_qf ocfs2 4 C 4066 10d 567d 0/29 upstream: reported C repro on 2024/10/03 18:26
linux-5.15 possible deadlock in ocfs2_lock_global_qf origin:lts-only 4 C done 303 54d 571d 0/3 upstream: reported C repro on 2024/09/29 22:07
linux-6.1 possible deadlock in ocfs2_lock_global_qf 4 264 105d 569d 0/3 auto-obsoleted due to no activity on 2026/03/20 02:14

Sample crash report:
JBD2: Ignoring recovery information on journal
ocfs2: Mounting device (7,3) on (node local, slot 0) with ordered data mode.
======================================================
WARNING: possible circular locking dependency detected
syzkaller #0 Not tainted
------------------------------------------------------
syz.3.881/9929 is trying to acquire lock:
ffff8880606d3f60 (&ocfs2_quota_ip_alloc_sem_key){++++}-{3:3}, at: ocfs2_lock_global_qf+0x202/0x290 fs/ocfs2/quota_global.c:314

but task is already holding lock:
ffff8880606d42d8 (&ocfs2_sysfile_lock_key[args->fi_sysfile_type]#7){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:804 [inline]
ffff8880606d42d8 (&ocfs2_sysfile_lock_key[args->fi_sysfile_type]#7){+.+.}-{3:3}, at: ocfs2_lock_global_qf+0x1db/0x290 fs/ocfs2/quota_global.c:313

which lock already depends on the new lock.


the existing dependency chain (in reverse order) is:

-> #4 (&ocfs2_sysfile_lock_key[args->fi_sysfile_type]#7){+.+.}-{3:3}:
       down_write+0x97/0x200 kernel/locking/rwsem.c:1573
       inode_lock include/linux/fs.h:804 [inline]
       ocfs2_lock_global_qf+0x1db/0x290 fs/ocfs2/quota_global.c:313
       ocfs2_acquire_dquot+0x2a1/0xb10 fs/ocfs2/quota_global.c:816
       dqget+0x77c/0xeb0 fs/quota/dquot.c:990
       __dquot_initialize+0x3c7/0xcd0 fs/quota/dquot.c:1518
       ocfs2_get_init_inode+0x148/0x1c0 fs/ocfs2/namei.c:202
       ocfs2_mknod+0x867/0x2300 fs/ocfs2/namei.c:310
       ocfs2_create+0x196/0x430 fs/ocfs2/namei.c:674
       lookup_open fs/namei.c:3496 [inline]
       open_last_lookups fs/namei.c:3564 [inline]
       path_openat+0x12a0/0x3230 fs/namei.c:3794
       do_filp_open+0x1f5/0x430 fs/namei.c:3824
       do_sys_openat2+0x134/0x1d0 fs/open.c:1421
       do_sys_open fs/open.c:1436 [inline]
       __do_sys_openat fs/open.c:1452 [inline]
       __se_sys_openat fs/open.c:1447 [inline]
       __x64_sys_openat+0x139/0x160 fs/open.c:1447
       do_syscall_x64 arch/x86/entry/common.c:46 [inline]
       do_syscall_64+0x55/0xa0 arch/x86/entry/common.c:76
       entry_SYSCALL_64_after_hwframe+0x68/0xd2

-> #3 (&dquot->dq_lock){+.+.}-{3:3}:
       __mutex_lock_common kernel/locking/mutex.c:603 [inline]
       __mutex_lock+0x136/0xcc0 kernel/locking/mutex.c:747
       wait_on_dquot fs/quota/dquot.c:358 [inline]
       dqget+0x6fc/0xeb0 fs/quota/dquot.c:985
       __dquot_initialize+0x3c7/0xcd0 fs/quota/dquot.c:1518
       ocfs2_get_init_inode+0x148/0x1c0 fs/ocfs2/namei.c:202
       ocfs2_mknod+0x867/0x2300 fs/ocfs2/namei.c:310
       ocfs2_create+0x196/0x430 fs/ocfs2/namei.c:674
       lookup_open fs/namei.c:3496 [inline]
       open_last_lookups fs/namei.c:3564 [inline]
       path_openat+0x12a0/0x3230 fs/namei.c:3794
       do_filp_open+0x1f5/0x430 fs/namei.c:3824
       do_sys_openat2+0x134/0x1d0 fs/open.c:1421
       do_sys_open fs/open.c:1436 [inline]
       __do_sys_openat fs/open.c:1452 [inline]
       __se_sys_openat fs/open.c:1447 [inline]
       __x64_sys_openat+0x139/0x160 fs/open.c:1447
       do_syscall_x64 arch/x86/entry/common.c:46 [inline]
       do_syscall_64+0x55/0xa0 arch/x86/entry/common.c:76
       entry_SYSCALL_64_after_hwframe+0x68/0xd2

-> #2 (&ocfs2_sysfile_lock_key[args->fi_sysfile_type]#2){+.+.}-{3:3}:
       down_write+0x97/0x200 kernel/locking/rwsem.c:1573
       inode_lock include/linux/fs.h:804 [inline]
       ocfs2_remove_inode fs/ocfs2/inode.c:655 [inline]
       ocfs2_wipe_inode fs/ocfs2/inode.c:818 [inline]
       ocfs2_delete_inode fs/ocfs2/inode.c:1079 [inline]
       ocfs2_evict_inode+0x1d84/0x41e0 fs/ocfs2/inode.c:1219
       evict+0x4ca/0x8d0 fs/inode.c:705
       d_delete_notify include/linux/fsnotify.h:269 [inline]
       vfs_rmdir+0x39b/0x4d0 fs/namei.c:4217
       do_rmdir+0x29f/0x590 fs/namei.c:4263
       __do_sys_rmdir fs/namei.c:4282 [inline]
       __se_sys_rmdir fs/namei.c:4280 [inline]
       __x64_sys_rmdir+0x49/0x50 fs/namei.c:4280
       do_syscall_x64 arch/x86/entry/common.c:46 [inline]
       do_syscall_64+0x55/0xa0 arch/x86/entry/common.c:76
       entry_SYSCALL_64_after_hwframe+0x68/0xd2

-> #1 (&ocfs2_sysfile_lock_key[args->fi_sysfile_type]){+.+.}-{3:3}:
       down_write+0x97/0x200 kernel/locking/rwsem.c:1573
       inode_lock include/linux/fs.h:804 [inline]
       ocfs2_del_inode_from_orphan+0x12f/0x7a0 fs/ocfs2/namei.c:2716
       ocfs2_dio_end_io_write fs/ocfs2/aops.c:2333 [inline]
       ocfs2_dio_end_io+0x546/0x1200 fs/ocfs2/aops.c:2431
       dio_complete+0x254/0x710 fs/direct-io.c:282
       __blockdev_direct_IO+0x2ea8/0x3500 fs/direct-io.c:1308
       ocfs2_direct_IO+0x235/0x2a0 fs/ocfs2/aops.c:2468
       generic_file_direct_write+0x1d4/0x3e0 mm/filemap.c:3961
       __generic_file_write_iter+0x11b/0x230 mm/filemap.c:4117
       ocfs2_file_write_iter+0x167a/0x1e80 fs/ocfs2/file.c:2468
       do_iter_readv_writev fs/read_write.c:-1 [inline]
       do_iter_write+0x738/0xc30 fs/read_write.c:860
       vfs_writev fs/read_write.c:933 [inline]
       do_pwritev+0x241/0x3a0 fs/read_write.c:1030
       do_syscall_x64 arch/x86/entry/common.c:46 [inline]
       do_syscall_64+0x55/0xa0 arch/x86/entry/common.c:76
       entry_SYSCALL_64_after_hwframe+0x68/0xd2

-> #0 (&ocfs2_quota_ip_alloc_sem_key){++++}-{3:3}:
       check_prev_add kernel/locking/lockdep.c:3134 [inline]
       check_prevs_add kernel/locking/lockdep.c:3253 [inline]
       validate_chain kernel/locking/lockdep.c:3869 [inline]
       __lock_acquire+0x2df1/0x7d40 kernel/locking/lockdep.c:5137
       lock_acquire+0x19e/0x420 kernel/locking/lockdep.c:5754
       down_write+0x97/0x200 kernel/locking/rwsem.c:1573
       ocfs2_lock_global_qf+0x202/0x290 fs/ocfs2/quota_global.c:314
       ocfs2_acquire_dquot+0x2a1/0xb10 fs/ocfs2/quota_global.c:816
       dqget+0x77c/0xeb0 fs/quota/dquot.c:990
       __dquot_initialize+0x3c7/0xcd0 fs/quota/dquot.c:1518
       ocfs2_get_init_inode+0x148/0x1c0 fs/ocfs2/namei.c:202
       ocfs2_mknod+0x867/0x2300 fs/ocfs2/namei.c:310
       ocfs2_create+0x196/0x430 fs/ocfs2/namei.c:674
       lookup_open fs/namei.c:3496 [inline]
       open_last_lookups fs/namei.c:3564 [inline]
       path_openat+0x12a0/0x3230 fs/namei.c:3794
       do_filp_open+0x1f5/0x430 fs/namei.c:3824
       do_sys_openat2+0x134/0x1d0 fs/open.c:1421
       do_sys_open fs/open.c:1436 [inline]
       __do_sys_openat fs/open.c:1452 [inline]
       __se_sys_openat fs/open.c:1447 [inline]
       __x64_sys_openat+0x139/0x160 fs/open.c:1447
       do_syscall_x64 arch/x86/entry/common.c:46 [inline]
       do_syscall_64+0x55/0xa0 arch/x86/entry/common.c:76
       entry_SYSCALL_64_after_hwframe+0x68/0xd2

other info that might help us debug this:

Chain exists of:
  &ocfs2_quota_ip_alloc_sem_key --> &dquot->dq_lock --> &ocfs2_sysfile_lock_key[args->fi_sysfile_type]#7

 Possible unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  lock(&ocfs2_sysfile_lock_key[args->fi_sysfile_type]#7);
                               lock(&dquot->dq_lock);
                               lock(&ocfs2_sysfile_lock_key[args->fi_sysfile_type]#7);
  lock(&ocfs2_quota_ip_alloc_sem_key);

 *** DEADLOCK ***

5 locks held by syz.3.881/9929:
 #0: ffff88806425a418 (sb_writers#29){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:412
 #1: ffff8880606d1818 (&type->i_mutex_dir_key#22){++++}-{3:3}, at: inode_lock include/linux/fs.h:804 [inline]
 #1: ffff8880606d1818 (&type->i_mutex_dir_key#22){++++}-{3:3}, at: open_last_lookups fs/namei.c:3561 [inline]
 #1: ffff8880606d1818 (&type->i_mutex_dir_key#22){++++}-{3:3}, at: path_openat+0x7dc/0x3230 fs/namei.c:3794
 #2: ffff88805befc2d8 (&ocfs2_sysfile_lock_key[args->fi_sysfile_type]#2){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:804 [inline]
 #2: ffff88805befc2d8 (&ocfs2_sysfile_lock_key[args->fi_sysfile_type]#2){+.+.}-{3:3}, at: ocfs2_reserve_suballoc_bits+0x16e/0x44c0 fs/ocfs2/suballoc.c:782
 #3: ffff88805bfca0a8 (&dquot->dq_lock){+.+.}-{3:3}, at: ocfs2_acquire_dquot+0x28f/0xb10 fs/ocfs2/quota_global.c:811
 #4: ffff8880606d42d8 (&ocfs2_sysfile_lock_key[args->fi_sysfile_type]#7){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:804 [inline]
 #4: ffff8880606d42d8 (&ocfs2_sysfile_lock_key[args->fi_sysfile_type]#7){+.+.}-{3:3}, at: ocfs2_lock_global_qf+0x1db/0x290 fs/ocfs2/quota_global.c:313

stack backtrace:
CPU: 1 PID: 9929 Comm: syz.3.881 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/18/2026
Call Trace:
 <TASK>
 dump_stack_lvl+0x18c/0x250 lib/dump_stack.c:106
 check_noncircular+0x2fc/0x400 kernel/locking/lockdep.c:2187
 check_prev_add kernel/locking/lockdep.c:3134 [inline]
 check_prevs_add kernel/locking/lockdep.c:3253 [inline]
 validate_chain kernel/locking/lockdep.c:3869 [inline]
 __lock_acquire+0x2df1/0x7d40 kernel/locking/lockdep.c:5137
 lock_acquire+0x19e/0x420 kernel/locking/lockdep.c:5754
 down_write+0x97/0x200 kernel/locking/rwsem.c:1573
 ocfs2_lock_global_qf+0x202/0x290 fs/ocfs2/quota_global.c:314
 ocfs2_acquire_dquot+0x2a1/0xb10 fs/ocfs2/quota_global.c:816
 dqget+0x77c/0xeb0 fs/quota/dquot.c:990
 __dquot_initialize+0x3c7/0xcd0 fs/quota/dquot.c:1518
 ocfs2_get_init_inode+0x148/0x1c0 fs/ocfs2/namei.c:202
 ocfs2_mknod+0x867/0x2300 fs/ocfs2/namei.c:310
 ocfs2_create+0x196/0x430 fs/ocfs2/namei.c:674
 lookup_open fs/namei.c:3496 [inline]
 open_last_lookups fs/namei.c:3564 [inline]
 path_openat+0x12a0/0x3230 fs/namei.c:3794
 do_filp_open+0x1f5/0x430 fs/namei.c:3824
 do_sys_openat2+0x134/0x1d0 fs/open.c:1421
 do_sys_open fs/open.c:1436 [inline]
 __do_sys_openat fs/open.c:1452 [inline]
 __se_sys_openat fs/open.c:1447 [inline]
 __x64_sys_openat+0x139/0x160 fs/open.c:1447
 do_syscall_x64 arch/x86/entry/common.c:46 [inline]
 do_syscall_64+0x55/0xa0 arch/x86/entry/common.c:76
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f0026d9c819
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 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 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f0027cc5028 EFLAGS: 00000246 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 00007f0027015fa0 RCX: 00007f0026d9c819
RDX: 0000000000040042 RSI: 0000200000000240 RDI: ffffffffffffff9c
RBP: 00007f0026e32c91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000001 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f0027016038 R14: 00007f0027015fa0 R15: 00007ffd554fc8c8
 </TASK>
(syz.3.881,9929,1):ocfs2_block_check_validate:402 ERROR: CRC32 failed: stored: 0x438, computed 0x1cec3d0f. Applying ECC.
(syz.3.881,9929,1):ocfs2_block_check_validate:416 ERROR: Fixed CRC32 failed: stored: 0x438, computed 0x1cec3d0f
(syz.3.881,9929,1):ocfs2_read_quota_phys_block:160 ERROR: status = -5
(syz.3.881,9929,1):ocfs2_quota_read:201 ERROR: status = -5
Quota error (device loop3): find_tree_dqentry: Can't read quota tree block 4
Quota error (device loop3): qtree_read_dquot: Can't read quota structure for id 0
(syz.3.881,9929,1):ocfs2_acquire_dquot:878 ERROR: status = -5
(syz.3.881,9929,1):ocfs2_mknod:314 ERROR: status = -5
(syz.3.881,9929,1):ocfs2_mknod:502 ERROR: status = -5
(syz.3.881,9929,1):ocfs2_create:676 ERROR: status = -5
(syz.3.881,9929,1):ocfs2_block_check_validate:402 ERROR: CRC32 failed: stored: 0x438, computed 0x1cec3d0f. Applying ECC.
(syz.3.881,9929,1):ocfs2_block_check_validate:416 ERROR: Fixed CRC32 failed: stored: 0x438, computed 0x1cec3d0f
(syz.3.881,9929,1):ocfs2_read_quota_phys_block:160 ERROR: status = -5
(syz.3.881,9929,1):ocfs2_quota_read:201 ERROR: status = -5
Quota error (device loop3): find_next_id: Can't read quota tree block 4
(syz.3.881,9929,1):ocfs2_get_next_id:909 ERROR: status = -5

Crashes (2):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/04/23 03:43 linux-6.6.y 9760bf04666d b10da5ec .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan possible deadlock in ocfs2_lock_global_qf
2026/02/22 05:27 linux-6.6.y 7a137e9bfa0e 6e7b5511 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan possible deadlock in ocfs2_lock_global_qf
* Struck through repros no longer work on HEAD.