syzbot


kernel BUG in gfs2_unpin

Status: upstream: reported on 2025/12/27 10:57
Subsystems: gfs2
Labels: prio:normal
[Documentation on labels]
Reported-by: syzbot+0c5024a57ccf4017c187@syzkaller.appspotmail.com
First crash: 170d, last: 3d09h
✨ AI Jobs (1)
ID Workflow Result Correct Bug Created Started Finished Revision Error
6fffecd8-c88a-4d0d-8669-ab4425e4af39 assessment-security DenialOfService: ✅ Exploitable: ❌ FilesystemTrigger: ✅ NetworkTrigger: ❌ PeripheralTrigger: ❌ RemoteTrigger: ❌ Unprivileged: ❌ UserNamespace: ❌ VMGuestTrigger: ❌ VMHostTrigger: ❌ kernel BUG in gfs2_unpin 2026/05/25 07:01 2026/05/25 07:01 2026/05/25 07:50 c69befb30ac10e158cc9d1557b508ee3f0eca1de
Discussions (1)
Title Replies (including bot) Last reply
[syzbot] [gfs2?] kernel BUG in gfs2_unpin 0 (1) 2025/12/27 10:57

Sample crash report:
loop0: detected capacity change from 0 to 32768
gfs2: fsid=syz:syz: Trying to join cluster "lock_nolock", "syz:syz"
gfs2: fsid=syz:syz: Now mounting FS (format 1801)...
gfs2: fsid=syz:syz.0: journal 0 mapped with 9 extents in 0ms
gfs2: fsid=syz:syz.0: first mount done, others may mount
gfs2: fsid=syz:syz.0: found 1 quota changes
syz.0.0: attempt to access beyond end of device
loop0: rw=2049, sector=68719479096, nr_sectors = 8 limit=32768
Buffer I/O error on dev loop0, logical block 8589934887, lost async page write
------------[ cut here ]------------
kernel BUG at fs/gfs2/lops.c:107!
Oops: invalid opcode: 0000 [#1] SMP KASAN NOPTI
CPU: 0 UID: 0 PID: 5328 Comm: syz.0.0 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2 04/01/2014
RIP: 0010:gfs2_unpin+0x9aa/0x9c0 fs/gfs2/lops.c:107
Code: fe e9 24 fb ff ff 44 89 e1 80 e1 07 80 c1 03 38 c1 0f 8c 52 fb ff ff 4c 89 e7 e8 11 f6 0d fe e9 45 fb ff ff e8 07 0f a1 fd 90 <0f> 0b e8 ff 0e a1 fd 90 0f 0b e8 f7 0e a1 fd 90 0f 0b 0f 1f 40 00
RSP: 0018:ffffc90005757330 EFLAGS: 00010283
RAX: ffffffff8424b849 RBX: ffff88801f5e5100 RCX: 0000000000100000
RDX: ffffc90020802000 RSI: 000000000000953f RDI: 0000000000009540
RBP: 1ffff11003ebca3d R08: ffff8880119ba747 R09: 1ffff110023374e8
R10: dffffc0000000000 R11: ffffed10023374e9 R12: dffffc0000000000
R13: ffff88801f5e17e0 R14: ffff8880119ba740 R15: ffff8880340f8000
FS:  00007f5ea3d836c0(0000) GS:ffff88808c894000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f4b41657bc0 CR3: 000000001b302000 CR4: 0000000000352ef0
Call Trace:
 <TASK>
 databuf_lo_after_commit+0x15e/0x1b0 fs/gfs2/lops.c:1080
 lops_after_commit fs/gfs2/lops.h:51 [inline]
 __gfs2_log_flush+0xfb6/0x1dc0 fs/gfs2/log.c:1152
 gfs2_log_flush+0x34/0x50 fs/gfs2/log.c:1216
 gfs2_jdata_writepages+0xf9/0x150 fs/gfs2/aops.c:371
 do_writepages+0x32e/0x550 mm/page-writeback.c:2571
 filemap_writeback mm/filemap.c:388 [inline]
 filemap_fdatawrite_range+0x1ef/0x2f0 mm/filemap.c:413
 gfs2_fsync+0xd8/0x370 fs/gfs2/file.c:752
 generic_write_sync include/linux/fs.h:2654 [inline]
 gfs2_file_write_iter+0xee4/0x1130 fs/gfs2/file.c:1168
 do_iter_readv_writev+0x619/0x8c0 fs/read_write.c:-1
 vfs_writev+0x33c/0x990 fs/read_write.c:1059
 do_pwritev fs/read_write.c:1155 [inline]
 __do_sys_pwritev2 fs/read_write.c:1213 [inline]
 __se_sys_pwritev2+0x184/0x2a0 fs/read_write.c:1204
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x174/0x580 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f5ea2f9ce59
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:00007f5ea3d82fe8 EFLAGS: 00000246 ORIG_RAX: 0000000000000148
RAX: ffffffffffffffda RBX: 00007f5ea3215fa0 RCX: 00007f5ea2f9ce59
RDX: 0000000000000001 RSI: 0000200000001100 RDI: 0000000000000008
RBP: 00007f5ea3032d6f R08: 0000000000000000 R09: 0000000000000003
R10: 0000000000007000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f5ea3216038 R14: 00007f5ea3215fa0 R15: 00007ffc7dfc3b38
 </TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:gfs2_unpin+0x9aa/0x9c0 fs/gfs2/lops.c:107
Code: fe e9 24 fb ff ff 44 89 e1 80 e1 07 80 c1 03 38 c1 0f 8c 52 fb ff ff 4c 89 e7 e8 11 f6 0d fe e9 45 fb ff ff e8 07 0f a1 fd 90 <0f> 0b e8 ff 0e a1 fd 90 0f 0b e8 f7 0e a1 fd 90 0f 0b 0f 1f 40 00
RSP: 0018:ffffc90005757330 EFLAGS: 00010283
RAX: ffffffff8424b849 RBX: ffff88801f5e5100 RCX: 0000000000100000
RDX: ffffc90020802000 RSI: 000000000000953f RDI: 0000000000009540
RBP: 1ffff11003ebca3d R08: ffff8880119ba747 R09: 1ffff110023374e8
R10: dffffc0000000000 R11: ffffed10023374e9 R12: dffffc0000000000
R13: ffff88801f5e17e0 R14: ffff8880119ba740 R15: ffff8880340f8000
FS:  00007f5ea3d836c0(0000) GS:ffff88808c894000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f5e9f3f4ff8 CR3: 000000001b302000 CR4: 0000000000352ef0

Crashes (10):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/06/08 03:46 upstream 33d8d8ec31b5 cc095639 .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root kernel BUG in gfs2_unpin
2026/05/27 02:52 upstream d60ec36cab33 2b01f00e .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root kernel BUG in gfs2_unpin
2026/04/12 08:32 upstream e753c16cb3dd 38c8e246 .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root kernel BUG in gfs2_unpin
2026/03/23 21:51 upstream c369299895a5 4933dba2 .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root kernel BUG in gfs2_unpin
2026/03/06 09:46 upstream 5ee8dbf54602 31e9c887 .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root kernel BUG in gfs2_unpin
2026/02/28 00:32 upstream a75cb869a8cc 2cf092b8 .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root kernel BUG in gfs2_unpin
2026/01/19 08:28 upstream 54e82e93ca93 d1b870e1 .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root kernel BUG in gfs2_unpin
2026/01/03 21:18 upstream 805f9a061372 d1b870e1 .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root kernel BUG in gfs2_unpin
2025/12/28 13:20 upstream d26143bb38e2 d1b870e1 .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root kernel BUG in gfs2_unpin
2025/12/23 10:51 upstream b927546677c8 d1b870e1 .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root kernel BUG in gfs2_unpin
* Struck through repros no longer work on HEAD.