syzbot |
sign-in | mailing list | source | docs |
| Kernel | Title | Rank 🛈 | Repro | Cause bisect | Fix bisect | Count | Last | Reported | Patched | Status |
|---|---|---|---|---|---|---|---|---|---|---|
| linux-6.6 | possible deadlock in dqget | 4 | 25 | 1d00h | 137d | 0/2 | upstream: reported on 2025/06/20 12:37 | |||
| linux-6.1 | possible deadlock in dqget | 4 | 1 | 280d | 280d | 0/3 | auto-obsoleted due to no activity on 2025/05/07 22:20 | |||
| upstream | possible deadlock in dqget ext4 ocfs2 | 4 | C | error | 91359 | now | 399d | 0/29 | upstream: reported C repro on 2024/10/01 08:09 |
loop3: detected capacity change from 0 to 512
EXT4-fs: Journaled quota options ignored when QUOTA feature is enabled
EXT4-fs (loop3): mounted filesystem without journal. Quota mode: writeback.
======================================================
WARNING: possible circular locking dependency detected
syzkaller #0 Not tainted
------------------------------------------------------
syz.3.13039/1380 is trying to acquire lock:
ffff88804cc413e8 (&dquot->dq_lock){+.+.}-{3:3}, at: wait_on_dquot fs/quota/dquot.c:356 [inline]
ffff88804cc413e8 (&dquot->dq_lock){+.+.}-{3:3}, at: dqget+0x6f8/0xeb0 fs/quota/dquot.c:983
but task is already holding lock:
ffff8880253e32f0 (&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_modify_bh+0xe5/0x460 fs/ocfs2/quota_local.c:101
ocfs2_local_read_info+0x13b1/0x16e0 fs/ocfs2/quota_local.c:764
dquot_load_quota_sb+0x756/0xac0 fs/quota/dquot.c:2470
dquot_load_quota_inode+0x2d8/0x5d0 fs/quota/dquot.c:2507
ocfs2_enable_quotas+0x1c3/0x440 fs/ocfs2/super.c:926
ocfs2_fill_super+0x409f/0x4d00 fs/ocfs2/super.c:1139
mount_bdev+0x287/0x3c0 fs/super.c:1443
legacy_get_tree+0xe6/0x180 fs/fs_context.c:632
vfs_get_tree+0x88/0x270 fs/super.c:1573
do_new_mount+0x24a/0xa40 fs/namespace.c:3069
do_mount fs/namespace.c:3412 [inline]
__do_sys_mount fs/namespace.c:3620 [inline]
__se_sys_mount+0x2d6/0x3c0 fs/namespace.c:3597
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
-> #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_modify_bh+0xe5/0x460 fs/ocfs2/quota_local.c:101
ocfs2_local_read_info+0x13b1/0x16e0 fs/ocfs2/quota_local.c:764
dquot_load_quota_sb+0x756/0xac0 fs/quota/dquot.c:2470
dquot_load_quota_inode+0x2d8/0x5d0 fs/quota/dquot.c:2507
ocfs2_enable_quotas+0x1c3/0x440 fs/ocfs2/super.c:926
ocfs2_fill_super+0x409f/0x4d00 fs/ocfs2/super.c:1139
mount_bdev+0x287/0x3c0 fs/super.c:1443
legacy_get_tree+0xe6/0x180 fs/fs_context.c:632
vfs_get_tree+0x88/0x270 fs/super.c:1573
do_new_mount+0x24a/0xa40 fs/namespace.c:3069
do_mount fs/namespace.c:3412 [inline]
__do_sys_mount fs/namespace.c:3620 [inline]
__se_sys_mount+0x2d6/0x3c0 fs/namespace.c:3597
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
-> #2 (sb_internal#4){.+.+}-{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_set_dqblk+0x27/0xf90 fs/quota/dquot.c:2833
quota_setquota+0x4ac/0x530 fs/quota/quota.c:310
__do_sys_quotactl fs/quota/quota.c:960 [inline]
__se_sys_quotactl+0x295/0x6b0 fs/quota/quota.c:916
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_set_dqblk+0x27/0xf90 fs/quota/dquot.c:2833
quota_setquota+0x4ac/0x530 fs/quota/quota.c:310
__do_sys_quotactl fs/quota/quota.c:960 [inline]
__se_sys_quotactl+0x295/0x6b0 fs/quota/quota.c:916
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_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
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.3.13039/1380:
#0: ffff88801e360460 (sb_writers#4){.+.+}-{0:0}, at: mnt_want_write+0x3d/0x90 fs/namespace.c:393
#1: ffff8880253e3628 (&sb->s_type->i_mutex_key#8){++++}-{3:3}, at: inode_lock include/linux/fs.h:758 [inline]
#1: ffff8880253e3628 (&sb->s_type->i_mutex_key#8){++++}-{3:3}, at: chown_common+0x320/0x620 fs/open.c:726
#2: ffff8880253e32f0 (&ei->xattr_sem){++++}-{3:3}, at: ext4_setattr+0x92a/0x19f0 fs/ext4/inode.c:5501
stack backtrace:
CPU: 0 PID: 1380 Comm: syz.3.13039 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025
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_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
RIP: 0033:0x7f8a01f8efc9
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:00007f8a02f13038 EFLAGS: 00000246 ORIG_RAX: 000000000000005c
RAX: ffffffffffffffda RBX: 00007f8a021e5fa0 RCX: 00007f8a01f8efc9
RDX: 0000000000000000 RSI: 000000000000ee00 RDI: 0000200000000240
RBP: 00007f8a02011f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f8a021e6038 R14: 00007f8a021e5fa0 R15: 00007fff9bb96918
</TASK>
| Time | Kernel | Commit | Syzkaller | Config | Log | Report | Syz repro | C repro | VM info | Assets (help?) | Manager | Title |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 2025/10/17 22:02 | linux-6.1.y | c2fda4b3f577 | 1c8c8cd8 | .config | console log | report | info | [disk image] [vmlinux] [kernel image] | ci2-linux-6-1-kasan | possible deadlock in dqget | ||
| 2025/10/15 16:48 | linux-6.1.y | c2fda4b3f577 | 19568248 | .config | console log | report | info | [disk image] [vmlinux] [kernel image] | ci2-linux-6-1-kasan | possible deadlock in dqget | ||
| 2025/09/29 11:21 | linux-6.1.y | 7b34dc04e4ff | 86341da6 | .config | console log | report | info | [disk image] [vmlinux] [kernel image] | ci2-linux-6-1-kasan | possible deadlock in dqget | ||
| 2025/09/19 15:47 | linux-6.1.y | 363a599da6d9 | 67c37560 | .config | console log | report | info | [disk image] [vmlinux] [kernel image] | ci2-linux-6-1-kasan | possible deadlock in dqget | ||
| 2025/09/02 13:25 | linux-6.1.y | f89b6e15694c | 96a211bc | .config | console log | report | info | [disk image] [vmlinux] [kernel image] | ci2-linux-6-1-kasan | possible deadlock in dqget | ||
| 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 | ||
| 2025/10/22 18:00 | linux-6.1.y | 8e6e2188d949 | c0460fcd | .config | console log | report | info | [disk image] [vmlinux] [kernel image] | ci2-linux-6-1-kasan-arm64 | possible deadlock in dqget | ||
| 2025/08/28 15:29 | linux-6.1.y | f89b6e15694c | e12e5ba4 | .config | console log | report | info | [disk image] [vmlinux] [kernel image] | ci2-linux-6-1-kasan-arm64 | 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 |