| Date | Name | Commit | Repro | Result |
|---|---|---|---|---|
| 2025/07/25 | upstream (ToT) | 327579671a9b | syz | [report] possible deadlock in kernfs_seq_start |
syzbot |
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| Date | Name | Commit | Repro | Result |
|---|---|---|---|---|
| 2025/07/25 | upstream (ToT) | 327579671a9b | syz | [report] possible deadlock in kernfs_seq_start |
| Kernel | Title | Rank 🛈 | Repro | Cause bisect | Fix bisect | Count | Last | Reported | Patched | Status |
|---|---|---|---|---|---|---|---|---|---|---|
| upstream | possible deadlock in seq_read_iter (4) overlayfs autofs | 4 | 69 | 1d10h | 456d | 0/29 | closed as dup on 2024/05/27 09:33 | |||
| linux-5.15 | possible deadlock in seq_read_iter | 4 | 64 | 12d | 485d | 0/3 | upstream: reported on 2024/04/28 04:21 | |||
| upstream | possible deadlock in seq_read_iter (2) overlayfs | 4 | C | done | done | 14 | 609d | 769d | 25/29 | fixed on 2024/02/02 10:05 |
| upstream | possible deadlock in seq_read_iter fs | 4 | 2 | 1481d | 1487d | 0/29 | auto-closed as invalid on 2021/12/05 03:01 | |||
| upstream | possible deadlock in seq_read_iter (3) overlayfs | 4 | 148 | 472d | 561d | 25/29 | fixed on 2024/05/23 00:16 |
======================================================
WARNING: possible circular locking dependency detected
6.6.99-syzkaller #0 Not tainted
------------------------------------------------------
syz.0.16/5942 is trying to acquire lock:
ffff8880252878b8 (&p->lock){+.+.}-{3:3}, at: seq_read_iter+0xb1/0xd50 fs/seq_file.c:182
but task is already holding lock:
ffff88802e796068 (&pipe->mutex/1){+.+.}-{3:3}, at: splice_file_to_pipe+0x2a/0x110 fs/splice.c:1230
which lock already depends on the new lock.
the existing dependency chain (in reverse order) is:
-> #3 (&pipe->mutex/1){+.+.}-{3:3}:
__mutex_lock_common kernel/locking/mutex.c:603 [inline]
__mutex_lock+0x129/0xcc0 kernel/locking/mutex.c:747
__pipe_lock fs/pipe.c:103 [inline]
pipe_write+0x1c7/0x1af0 fs/pipe.c:444
__kernel_write_iter+0x274/0x670 fs/read_write.c:517
__kernel_write+0xf0/0x140 fs/read_write.c:537
autofs_write fs/autofs/waitq.c:57 [inline]
autofs_notify_daemon+0x6ff/0xdc0 fs/autofs/waitq.c:164
autofs_wait+0x1021/0x1a40 fs/autofs/waitq.c:426
autofs_mount_wait+0x16b/0x320 fs/autofs/root.c:255
autofs_d_automount+0x392/0x710 fs/autofs/root.c:401
follow_automount fs/namei.c:1370 [inline]
__traverse_mounts+0x2fa/0x5a0 fs/namei.c:1415
traverse_mounts fs/namei.c:1444 [inline]
handle_mounts fs/namei.c:1547 [inline]
step_into+0x526/0xf10 fs/namei.c:1840
lookup_last fs/namei.c:2459 [inline]
path_lookupat+0x169/0x440 fs/namei.c:2483
filename_lookup+0x1f4/0x510 fs/namei.c:2512
kern_path+0x35/0x50 fs/namei.c:2610
lookup_bdev+0xc1/0x280 block/bdev.c:976
resume_store+0x16a/0x450 kernel/power/hibernate.c:1187
kernfs_fop_write_iter+0x37d/0x4d0 fs/kernfs/file.c:334
call_write_iter include/linux/fs.h:2018 [inline]
new_sync_write fs/read_write.c:491 [inline]
vfs_write+0x43b/0x940 fs/read_write.c:584
ksys_write+0x147/0x250 fs/read_write.c:637
do_syscall_x64 arch/x86/entry/common.c:51 [inline]
do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:81
entry_SYSCALL_64_after_hwframe+0x68/0xd2
-> #2 (&sbi->pipe_mutex){+.+.}-{3:3}:
__mutex_lock_common kernel/locking/mutex.c:603 [inline]
__mutex_lock+0x129/0xcc0 kernel/locking/mutex.c:747
autofs_write fs/autofs/waitq.c:55 [inline]
autofs_notify_daemon+0x6ec/0xdc0 fs/autofs/waitq.c:164
autofs_wait+0x1021/0x1a40 fs/autofs/waitq.c:426
autofs_mount_wait+0x16b/0x320 fs/autofs/root.c:255
autofs_d_automount+0x392/0x710 fs/autofs/root.c:401
follow_automount fs/namei.c:1370 [inline]
__traverse_mounts+0x2fa/0x5a0 fs/namei.c:1415
traverse_mounts fs/namei.c:1444 [inline]
handle_mounts fs/namei.c:1547 [inline]
step_into+0x526/0xf10 fs/namei.c:1840
lookup_last fs/namei.c:2459 [inline]
path_lookupat+0x169/0x440 fs/namei.c:2483
filename_lookup+0x1f4/0x510 fs/namei.c:2512
kern_path+0x35/0x50 fs/namei.c:2610
lookup_bdev+0xc1/0x280 block/bdev.c:976
resume_store+0x16a/0x450 kernel/power/hibernate.c:1187
kernfs_fop_write_iter+0x37d/0x4d0 fs/kernfs/file.c:334
call_write_iter include/linux/fs.h:2018 [inline]
new_sync_write fs/read_write.c:491 [inline]
vfs_write+0x43b/0x940 fs/read_write.c:584
ksys_write+0x147/0x250 fs/read_write.c:637
do_syscall_x64 arch/x86/entry/common.c:51 [inline]
do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:81
entry_SYSCALL_64_after_hwframe+0x68/0xd2
-> #1 (&of->mutex){+.+.}-{3:3}:
__mutex_lock_common kernel/locking/mutex.c:603 [inline]
__mutex_lock+0x129/0xcc0 kernel/locking/mutex.c:747
kernfs_seq_start+0x55/0x3b0 fs/kernfs/file.c:154
seq_read_iter+0x3c8/0xd50 fs/seq_file.c:225
call_read_iter include/linux/fs.h:2012 [inline]
new_sync_read fs/read_write.c:389 [inline]
vfs_read+0x431/0x920 fs/read_write.c:470
ksys_read+0x147/0x250 fs/read_write.c:613
do_syscall_x64 arch/x86/entry/common.c:51 [inline]
do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:81
entry_SYSCALL_64_after_hwframe+0x68/0xd2
-> #0 (&p->lock){+.+.}-{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+0x2ddb/0x7c80 kernel/locking/lockdep.c:5137
lock_acquire+0x197/0x410 kernel/locking/lockdep.c:5754
__mutex_lock_common kernel/locking/mutex.c:603 [inline]
__mutex_lock+0x129/0xcc0 kernel/locking/mutex.c:747
seq_read_iter+0xb1/0xd50 fs/seq_file.c:182
call_read_iter include/linux/fs.h:2012 [inline]
copy_splice_read+0x3c8/0x860 fs/splice.c:364
splice_file_to_pipe+0x6e/0x110 fs/splice.c:1233
do_sendfile+0x572/0xf70 fs/read_write.c:1261
__do_sys_sendfile64 fs/read_write.c:1322 [inline]
__se_sys_sendfile64+0x13f/0x190 fs/read_write.c:1308
do_syscall_x64 arch/x86/entry/common.c:51 [inline]
do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:81
entry_SYSCALL_64_after_hwframe+0x68/0xd2
other info that might help us debug this:
Chain exists of:
&p->lock --> &sbi->pipe_mutex --> &pipe->mutex/1
Possible unsafe locking scenario:
CPU0 CPU1
---- ----
lock(&pipe->mutex/1);
lock(&sbi->pipe_mutex);
lock(&pipe->mutex/1);
lock(&p->lock);
*** DEADLOCK ***
1 lock held by syz.0.16/5942:
#0: ffff88802e796068 (&pipe->mutex/1){+.+.}-{3:3}, at: splice_file_to_pipe+0x2a/0x110 fs/splice.c:1230
stack backtrace:
CPU: 0 PID: 5942 Comm: syz.0.16 Not tainted 6.6.99-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
Call Trace:
<TASK>
dump_stack_lvl+0x16c/0x230 lib/dump_stack.c:106
check_noncircular+0x2bd/0x3c0 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+0x2ddb/0x7c80 kernel/locking/lockdep.c:5137
lock_acquire+0x197/0x410 kernel/locking/lockdep.c:5754
__mutex_lock_common kernel/locking/mutex.c:603 [inline]
__mutex_lock+0x129/0xcc0 kernel/locking/mutex.c:747
seq_read_iter+0xb1/0xd50 fs/seq_file.c:182
call_read_iter include/linux/fs.h:2012 [inline]
copy_splice_read+0x3c8/0x860 fs/splice.c:364
splice_file_to_pipe+0x6e/0x110 fs/splice.c:1233
do_sendfile+0x572/0xf70 fs/read_write.c:1261
__do_sys_sendfile64 fs/read_write.c:1322 [inline]
__se_sys_sendfile64+0x13f/0x190 fs/read_write.c:1308
do_syscall_x64 arch/x86/entry/common.c:51 [inline]
do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:81
entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f4e04d8e9a9
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:00007f4e05b68038 EFLAGS: 00000246 ORIG_RAX: 0000000000000028
RAX: ffffffffffffffda RBX: 00007f4e04fb6080 RCX: 00007f4e04d8e9a9
RDX: 0000000000000000 RSI: 0000000000000004 RDI: 0000000000000000
RBP: 00007f4e04e10d69 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000004 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007f4e04fb6080 R15: 00007fff7478f678
</TASK>
| Time | Kernel | Commit | Syzkaller | Config | Log | Report | Syz repro | C repro | VM info | Assets (help?) | Manager | Title |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 2025/07/20 22:15 | linux-6.6.y | d96eb99e2f0e | 7117feec | .config | console log | report | syz / log | [disk image] [vmlinux] [kernel image] | ci2-linux-6-6-kasan | possible deadlock in seq_read_iter | ||
| 2025/07/20 18:43 | linux-6.6.y | d96eb99e2f0e | 7117feec | .config | console log | report | syz / log | [disk image] [vmlinux] [kernel image] | ci2-linux-6-6-kasan | possible deadlock in seq_read_iter | ||
| 2025/07/20 15:36 | linux-6.6.y | d96eb99e2f0e | 7117feec | .config | console log | report | syz / log | [disk image] [vmlinux] [kernel image] | ci2-linux-6-6-kasan | possible deadlock in seq_read_iter | ||
| 2025/07/20 12:24 | linux-6.6.y | d96eb99e2f0e | 7117feec | .config | console log | report | syz / log | [disk image] [vmlinux] [kernel image] | ci2-linux-6-6-kasan | possible deadlock in seq_read_iter | ||
| 2025/07/20 09:19 | linux-6.6.y | d96eb99e2f0e | 7117feec | .config | console log | report | syz / log | [disk image] [vmlinux] [kernel image] | ci2-linux-6-6-kasan | possible deadlock in seq_read_iter | ||
| 2025/07/28 19:41 | linux-6.6.y | dbcb8d8e4163 | 6654ea9c | .config | console log | report | info | [disk image] [vmlinux] [kernel image] | ci2-linux-6-6-kasan | possible deadlock in seq_read_iter | ||
| 2025/07/16 19:15 | linux-6.6.y | 9247f4e6573a | 124ec9cc | .config | console log | report | info | [disk image] [vmlinux] [kernel image] | ci2-linux-6-6-kasan | possible deadlock in seq_read_iter |