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| Kernel | Title | Rank 🛈 | Repro | Cause bisect | Fix bisect | Count | Last | Reported | Patched | Status |
|---|---|---|---|---|---|---|---|---|---|---|
| linux-6.6 | possible deadlock in dqget | 4 | 13 | 25d | 67d | 0/2 | upstream: reported on 2025/06/20 12:37 | |||
| linux-6.1 | possible deadlock in dqget | 4 | 1 | 210d | 210d | 0/3 | auto-obsoleted due to no activity on 2025/05/07 22:20 | |||
| upstream | possible deadlock in dqget ocfs2 ext4 | 4 | C | error | 77667 | 8m | 329d | 0/29 | upstream: reported C repro on 2024/10/01 08:09 |
EXT4-fs: Quota format mount options ignored when QUOTA feature is enabled
EXT4-fs (loop0): mounted filesystem without journal. Quota mode: writeback.
======================================================
WARNING: possible circular locking dependency detected
6.1.147-syzkaller #0 Not tainted
------------------------------------------------------
syz.0.12458/4767 is trying to acquire lock:
ffff8880587d67a8 (&dquot->dq_lock){+.+.}-{3:3}, at: wait_on_dquot fs/quota/dquot.c:356 [inline]
ffff8880587d67a8 (&dquot->dq_lock){+.+.}-{3:3}, at: dqget+0x6f8/0xeb0 fs/quota/dquot.c:983
but task is already holding lock:
ffff8880535f6518 (&ei->xattr_sem){++++}-{3:3}, at: ext4_setattr+0x92a/0x19f0 fs/ext4/inode.c:5501
which lock already depends on the new lock.
the existing dependency chain (in reverse order) is:
-> #5 (&ei->xattr_sem){++++}-{3:3}:
down_read+0x42/0x2d0 kernel/locking/rwsem.c:1520
ext4_setattr+0x92a/0x19f0 fs/ext4/inode.c:5501
notify_change+0xc74/0xf40 fs/attr.c:499
chown_common+0x486/0x620 fs/open.c:736
do_fchownat+0x164/0x270 fs/open.c:767
__do_sys_chown fs/open.c:787 [inline]
__se_sys_chown fs/open.c:785 [inline]
__x64_sys_chown+0x7e/0x90 fs/open.c:785
do_syscall_x64 arch/x86/entry/common.c:51 [inline]
do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:81
entry_SYSCALL_64_after_hwframe+0x68/0xd2
-> #4 (jbd2_handle){++++}-{0:0}:
start_this_handle+0x1f49/0x2150 fs/jbd2/transaction.c:463
jbd2__journal_start+0x2b7/0x5a0 fs/jbd2/transaction.c:520
jbd2_journal_start+0x26/0x30 fs/jbd2/transaction.c:559
ocfs2_start_trans+0x372/0x6c0 fs/ocfs2/journal.c:376
ocfs2_shutdown_local_alloc+0x1fd/0xa10 fs/ocfs2/localalloc.c:416
ocfs2_dismount_volume+0x1fc/0x930 fs/ocfs2/super.c:1882
generic_shutdown_super+0x130/0x340 fs/super.c:501
kill_block_super+0x7c/0xe0 fs/super.c:1470
deactivate_locked_super+0x93/0xf0 fs/super.c:332
cleanup_mnt+0x463/0x4f0 fs/namespace.c:1182
task_work_run+0x1ca/0x250 kernel/task_work.c:203
resume_user_mode_work include/linux/resume_user_mode.h:49 [inline]
exit_to_user_mode_loop+0xe6/0x110 kernel/entry/common.c:177
exit_to_user_mode_prepare+0xb1/0x140 kernel/entry/common.c:210
__syscall_exit_to_user_mode_work kernel/entry/common.c:292 [inline]
syscall_exit_to_user_mode+0x16/0x40 kernel/entry/common.c:303
do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:87
entry_SYSCALL_64_after_hwframe+0x68/0xd2
-> #3 (&journal->j_trans_barrier){.+.+}-{3:3}:
down_read+0x42/0x2d0 kernel/locking/rwsem.c:1520
ocfs2_start_trans+0x366/0x6c0 fs/ocfs2/journal.c:374
ocfs2_shutdown_local_alloc+0x1fd/0xa10 fs/ocfs2/localalloc.c:416
ocfs2_dismount_volume+0x1fc/0x930 fs/ocfs2/super.c:1882
generic_shutdown_super+0x130/0x340 fs/super.c:501
kill_block_super+0x7c/0xe0 fs/super.c:1470
deactivate_locked_super+0x93/0xf0 fs/super.c:332
cleanup_mnt+0x463/0x4f0 fs/namespace.c:1182
task_work_run+0x1ca/0x250 kernel/task_work.c:203
resume_user_mode_work include/linux/resume_user_mode.h:49 [inline]
exit_to_user_mode_loop+0xe6/0x110 kernel/entry/common.c:177
exit_to_user_mode_prepare+0xb1/0x140 kernel/entry/common.c:210
__syscall_exit_to_user_mode_work kernel/entry/common.c:292 [inline]
syscall_exit_to_user_mode+0x16/0x40 kernel/entry/common.c:303
do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:87
entry_SYSCALL_64_after_hwframe+0x68/0xd2
-> #2 (sb_internal#2){.+.+}-{0:0}:
percpu_down_read include/linux/percpu-rwsem.h:51 [inline]
__sb_start_write include/linux/fs.h:1891 [inline]
sb_start_intwrite include/linux/fs.h:2013 [inline]
ocfs2_start_trans+0x267/0x6c0 fs/ocfs2/journal.c:372
ocfs2_acquire_dquot+0x66e/0xb10 fs/ocfs2/quota_global.c:848
dqget+0x778/0xeb0 fs/quota/dquot.c:988
__dquot_initialize+0x3b6/0xcb0 fs/quota/dquot.c:1517
ocfs2_get_init_inode+0x138/0x1b0 fs/ocfs2/namei.c:202
ocfs2_symlink+0xc09/0x2650 fs/ocfs2/namei.c:1875
vfs_symlink+0x247/0x3d0 fs/namei.c:4471
do_symlinkat+0x1ae/0x3f0 fs/namei.c:4500
__do_sys_symlink fs/namei.c:4522 [inline]
__se_sys_symlink fs/namei.c:4520 [inline]
__x64_sys_symlink+0x7a/0x90 fs/namei.c:4520
do_syscall_x64 arch/x86/entry/common.c:51 [inline]
do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:81
entry_SYSCALL_64_after_hwframe+0x68/0xd2
-> #1 (&ocfs2_quota_ip_alloc_sem_key){++++}-{3:3}:
down_write+0x36/0x60 kernel/locking/rwsem.c:1573
ocfs2_create_local_dquot+0x1a0/0x1790 fs/ocfs2/quota_local.c:1224
ocfs2_acquire_dquot+0x7ae/0xb10 fs/ocfs2/quota_global.c:871
dqget+0x778/0xeb0 fs/quota/dquot.c:988
__dquot_initialize+0x3b6/0xcb0 fs/quota/dquot.c:1517
ocfs2_get_init_inode+0x138/0x1b0 fs/ocfs2/namei.c:202
ocfs2_symlink+0xc09/0x2650 fs/ocfs2/namei.c:1875
vfs_symlink+0x247/0x3d0 fs/namei.c:4471
do_symlinkat+0x1ae/0x3f0 fs/namei.c:4500
__do_sys_symlink fs/namei.c:4522 [inline]
__se_sys_symlink fs/namei.c:4520 [inline]
__x64_sys_symlink+0x7a/0x90 fs/namei.c:4520
do_syscall_x64 arch/x86/entry/common.c:51 [inline]
do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:81
entry_SYSCALL_64_after_hwframe+0x68/0xd2
-> #0 (&dquot->dq_lock){+.+.}-{3:3}:
check_prev_add kernel/locking/lockdep.c:3090 [inline]
check_prevs_add kernel/locking/lockdep.c:3209 [inline]
validate_chain kernel/locking/lockdep.c:3825 [inline]
__lock_acquire+0x2cf8/0x7c50 kernel/locking/lockdep.c:5049
lock_acquire+0x1b4/0x490 kernel/locking/lockdep.c:5662
__mutex_lock_common kernel/locking/mutex.c:603 [inline]
__mutex_lock+0x120/0xaf0 kernel/locking/mutex.c:747
wait_on_dquot fs/quota/dquot.c:356 [inline]
dqget+0x6f8/0xeb0 fs/quota/dquot.c:983
dquot_transfer+0x391/0x820 fs/quota/dquot.c:2150
ext4_setattr+0x93d/0x19f0 fs/ext4/inode.c:5502
notify_change+0xc74/0xf40 fs/attr.c:499
chown_common+0x486/0x620 fs/open.c:736
do_fchownat+0x164/0x270 fs/open.c:767
__do_sys_fchownat fs/open.c:782 [inline]
__se_sys_fchownat fs/open.c:779 [inline]
__x64_sys_fchownat+0xb1/0xc0 fs/open.c:779
do_syscall_x64 arch/x86/entry/common.c:51 [inline]
do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:81
entry_SYSCALL_64_after_hwframe+0x68/0xd2
other info that might help us debug this:
Chain exists of:
&dquot->dq_lock --> jbd2_handle --> &ei->xattr_sem
Possible unsafe locking scenario:
CPU0 CPU1
---- ----
lock(&ei->xattr_sem);
lock(jbd2_handle);
lock(&ei->xattr_sem);
lock(&dquot->dq_lock);
*** DEADLOCK ***
3 locks held by syz.0.12458/4767:
#0: ffff888064cba460 (sb_writers#4){.+.+}-{0:0}, at: mnt_want_write+0x3d/0x90 fs/namespace.c:393
#1: ffff8880535f6850 (&type->i_mutex_dir_key#3){++++}-{3:3}, at: inode_lock include/linux/fs.h:758 [inline]
#1: ffff8880535f6850 (&type->i_mutex_dir_key#3){++++}-{3:3}, at: chown_common+0x320/0x620 fs/open.c:726
#2: ffff8880535f6518 (&ei->xattr_sem){++++}-{3:3}, at: ext4_setattr+0x92a/0x19f0 fs/ext4/inode.c:5501
stack backtrace:
CPU: 0 PID: 4767 Comm: syz.0.12458 Not tainted 6.1.147-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
Call Trace:
<TASK>
dump_stack_lvl+0x168/0x22e lib/dump_stack.c:106
check_noncircular+0x274/0x310 kernel/locking/lockdep.c:2170
check_prev_add kernel/locking/lockdep.c:3090 [inline]
check_prevs_add kernel/locking/lockdep.c:3209 [inline]
validate_chain kernel/locking/lockdep.c:3825 [inline]
__lock_acquire+0x2cf8/0x7c50 kernel/locking/lockdep.c:5049
lock_acquire+0x1b4/0x490 kernel/locking/lockdep.c:5662
__mutex_lock_common kernel/locking/mutex.c:603 [inline]
__mutex_lock+0x120/0xaf0 kernel/locking/mutex.c:747
wait_on_dquot fs/quota/dquot.c:356 [inline]
dqget+0x6f8/0xeb0 fs/quota/dquot.c:983
dquot_transfer+0x391/0x820 fs/quota/dquot.c:2150
ext4_setattr+0x93d/0x19f0 fs/ext4/inode.c:5502
notify_change+0xc74/0xf40 fs/attr.c:499
chown_common+0x486/0x620 fs/open.c:736
do_fchownat+0x164/0x270 fs/open.c:767
__do_sys_fchownat fs/open.c:782 [inline]
__se_sys_fchownat fs/open.c:779 [inline]
__x64_sys_fchownat+0xb1/0xc0 fs/open.c:779
do_syscall_x64 arch/x86/entry/common.c:51 [inline]
do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:81
entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f901d18ebe9
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:00007f901e0e7038 EFLAGS: 00000246 ORIG_RAX: 0000000000000104
RAX: ffffffffffffffda RBX: 00007f901d3b5fa0 RCX: 00007f901d18ebe9
RDX: 000000000000ee01 RSI: 0000200000000100 RDI: ffffffffffffff9c
RBP: 00007f901d211e19 R08: 0000000000001000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f901d3b6038 R14: 00007f901d3b5fa0 R15: 00007fffb88f95d8
</TASK>
| Time | Kernel | Commit | Syzkaller | Config | Log | Report | Syz repro | C repro | VM info | Assets (help?) | Manager | Title |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 2025/08/07 10:40 | linux-6.1.y | 3594f306da12 | 04cffc22 | .config | console log | report | info | [disk image] [vmlinux] [kernel image] | ci2-linux-6-1-kasan | possible deadlock in dqget | ||
| 2025/06/30 17:33 | linux-6.1.y | 7e69c33e4858 | 6e83b42d | .config | console log | report | info | [disk image] [vmlinux] [kernel image] | ci2-linux-6-1-kasan | possible deadlock in dqget | ||
| 2025/08/22 03:31 | linux-6.1.y | 0bc96de781b4 | bf27483f | .config | console log | report | info | [disk image] [vmlinux] [kernel image] | ci2-linux-6-1-kasan-arm64 | possible deadlock in dqget | ||
| 2025/07/31 15:59 | linux-6.1.y | 3594f306da12 | 0c075d67 | .config | console log | report | info | [disk image] [vmlinux] [kernel image] | ci2-linux-6-1-kasan-arm64 | possible deadlock in dqget |