syzbot


WARNING in nilfs_sufile_do_free

Status: upstream: reported C repro on 2026/04/12 02:12
Bug presence: origin:lts-only
[Documentation on labels]
Reported-by: syzbot+f04081bbaaf0dd35cf1e@syzkaller.appspotmail.com
First crash: 10d, last: 10d
Bug presence (2)
Date Name Commit Repro Result
2026/04/12 linux-5.15.y (ToT) 91d48252ad4b C [report] WARNING in nilfs_sufile_do_free
2026/04/12 upstream (ToT) f5459048c38a C Didn't crash
Similar bugs (1)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-6.1 WARNING in nilfs_sufile_do_free -1 C 6 10d 10d 0/3 upstream: reported C repro on 2026/04/12 01:46
Fix bisection attempts (1)
Created Duration User Patch Repo Result
2026/04/12 06:57 4m fix candidate upstream error job log

Sample crash report:
loop0: detected capacity change from 0 to 4096
------------[ cut here ]------------
WARNING: CPU: 1 PID: 4338 at fs/nilfs2/sufile.c:475 nilfs_sufile_do_free+0x534/0x7d0 fs/nilfs2/sufile.c:475
Modules linked in:
CPU: 1 PID: 4338 Comm: syz.0.17 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/18/2026
RIP: 0010:nilfs_sufile_do_free+0x534/0x7d0 fs/nilfs2/sufile.c:475
Code: 87 67 fe eb 05 e8 bc 87 67 fe 48 83 c4 40 5b 41 5c 41 5d 41 5e 41 5f 5d c3 e8 a8 87 67 fe 0f 0b e9 a1 fc ff ff e8 9c 87 67 fe <0f> 0b e9 ca fc ff ff e8 90 87 67 fe e8 9b e3 ee fd e9 30 fd ff ff
RSP: 0018:ffffc9000320f168 EFLAGS: 00010293
RAX: ffffffff83119974 RBX: ffff888022fab000 RCX: ffff88807a58bb80
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 0000000000000000 R08: ffff88807a58bb80 R09: 0000000000000002
R10: 00000000ffffffef R11: 0000000000000000 R12: ffff88807a58d308
R13: ffff888022fab0bc R14: 1ffff110045f5617 R15: 00000000000000b0
FS:  00005555730bc500(0000) GS:ffff8880b9100000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b30563fff CR3: 00000000729ab000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 nilfs_sufile_updatev+0x39f/0x640 fs/nilfs2/sufile.c:196
 nilfs_sufile_freev fs/nilfs2/sufile.h:87 [inline]
 nilfs_segctor_collect_blocks fs/nilfs2/segment.c:1246 [inline]
 nilfs_segctor_collect fs/nilfs2/segment.c:1534 [inline]
 nilfs_segctor_do_construct+0x2032/0x6ca0 fs/nilfs2/segment.c:2090
 nilfs_segctor_construct+0x17b/0x690 fs/nilfs2/segment.c:2455
 nilfs_clean_segments+0x3ba/0xa30 fs/nilfs2/segment.c:2529
 nilfs_ioctl_clean_segments fs/nilfs2/ioctl.c:940 [inline]
 nilfs_ioctl+0x2052/0x2190 fs/nilfs2/ioctl.c:1304
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:874 [inline]
 __se_sys_ioctl+0xfa/0x170 fs/ioctl.c:860
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7f7199a3f819
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:00007ffd916891a8 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007f7199cb8fa0 RCX: 00007f7199a3f819
RDX: 0000200000000640 RSI: 0000000040786e88 RDI: 0000000000000004
RBP: 00007f7199ad5c91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f7199cb8fac R14: 00007f7199cb8fa0 R15: 00007f7199cb8fa0
 </TASK>

Crashes (3):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/04/12 03:09 linux-5.15.y 91d48252ad4b 38c8e246 .config console log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro] ci2-linux-5-15-kasan WARNING in nilfs_sufile_do_free
2026/04/12 02:43 linux-5.15.y 91d48252ad4b 38c8e246 .config console log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro] ci2-linux-5-15-kasan WARNING in nilfs_sufile_do_free
2026/04/12 02:12 linux-5.15.y 91d48252ad4b 38c8e246 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan WARNING in nilfs_sufile_do_free
* Struck through repros no longer work on HEAD.