syzbot


WARNING in __generic_file_fsync (3)

Status: moderation: reported on 2025/11/11 09:55
Subsystems: fs
[Documentation on labels]
Reported-by: syzbot+7c0236746bf7e401eb60@syzkaller.appspotmail.com
First crash: 66d, last: 66d
Similar bugs (4)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-5.15 WARNING in __generic_file_fsync -1 1 985d 985d 0/3 auto-obsoleted due to no activity on 2023/08/23 09:03
linux-5.15 WARNING in __generic_file_fsync (2) -1 1 737d 734d 0/3 auto-obsoleted due to no activity on 2024/04/15 05:26
upstream WARNING in __generic_file_fsync (2) fs -1 1 436d 432d 0/29 auto-obsoleted due to no activity on 2025/02/01 03:46
upstream WARNING in __generic_file_fsync fs -1 1 1054d 1050d 0/29 auto-obsoleted due to no activity on 2023/05/24 22:02

Sample crash report:
------------[ cut here ]------------
DEBUG_LOCKS_WARN_ON(rt_mutex_owner(lock) != current)
WARNING: CPU: 0 PID: 7218 at kernel/locking/rtmutex_common.h:182 debug_rt_mutex_unlock kernel/locking/rtmutex_common.h:182 [inline]
WARNING: CPU: 0 PID: 7218 at kernel/locking/rtmutex_common.h:182 rt_mutex_slowunlock+0x6ce/0x8a0 kernel/locking/rtmutex.c:1419
Modules linked in:
CPU: 0 UID: 0 PID: 7218 Comm: syz.0.230 Not tainted syzkaller #0 PREEMPT_{RT,(full)} 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025
RIP: 0010:debug_rt_mutex_unlock kernel/locking/rtmutex_common.h:182 [inline]
RIP: 0010:rt_mutex_slowunlock+0x6ce/0x8a0 kernel/locking/rtmutex.c:1419
Code: 0f b6 04 20 84 c0 0f 85 c6 01 00 00 83 3d 3d 28 14 04 00 75 19 90 48 c7 c7 a0 fd ea 8a 48 c7 c6 e0 fd ea 8a e8 03 e7 c0 f6 90 <0f> 0b 90 90 90 e9 2f fa ff ff 90 0f 0b 90 e9 53 fe ff ff be 02 00
RSP: 0018:ffffc9000cff7d20 EFLAGS: 00010046
RAX: aed03d5d82c43300 RBX: ffff88805d1db970 RCX: 0000000000080000
RDX: ffffc900103b3000 RSI: 0000000000000551 RDI: 0000000000000552
RBP: ffffc9000cff7e18 R08: 0000000000000000 R09: 0000000000000000
R10: dffffc0000000000 R11: ffffed101710487b R12: dffffc0000000000
R13: ffff88805d1db920 R14: 0000000000000a06 R15: 1ffff920019fefac
FS:  00007f2d05c246c0(0000) GS:ffff888126df9000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000000 CR3: 000000005b6f4000 CR4: 00000000003526f0
Call Trace:
 <TASK>
 inode_unlock include/linux/fs.h:990 [inline]
 __generic_file_fsync+0x15d/0x1b0 fs/libfs.c:1555
 generic_file_fsync+0x6f/0xf0 fs/libfs.c:1580
 vfs_fsync_range fs/sync.c:187 [inline]
 vfs_fsync fs/sync.c:201 [inline]
 do_fsync fs/sync.c:212 [inline]
 __do_sys_fsync fs/sync.c:217 [inline]
 __se_sys_fsync fs/sync.c:215 [inline]
 __x64_sys_fsync+0x194/0x1f0 fs/sync.c:215
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xfa/0xfa0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f2d079ff6c9
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:00007f2d05c24038 EFLAGS: 00000246 ORIG_RAX: 000000000000004a
RAX: ffffffffffffffda RBX: 00007f2d07c56180 RCX: 00007f2d079ff6c9
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000007
RBP: 00007f2d07a81f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f2d07c56218 R14: 00007f2d07c56180 R15: 00007ffd2c36d018
 </TASK>

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/11/07 09:48 upstream 4a0c9b339199 4e1406b4 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs WARNING in __generic_file_fsync
* Struck through repros no longer work on HEAD.