syzbot


general protection fault in gfs2_glock_dq (2)

Status: upstream: reported on 2025/12/26 11:22
Subsystems: gfs2
[Documentation on labels]
Reported-by: syzbot+5a5f492ccae698fd7434@syzkaller.appspotmail.com
First crash: 134d, last: 2d15h
Discussions (1)
Title Replies (including bot) Last reply
[syzbot] [gfs2?] general protection fault in gfs2_glock_dq (2) 0 (1) 2025/12/26 11:22
Similar bugs (3)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream general protection fault in gfs2_glock_dq gfs2 2 16 402d 524d 0/29 auto-obsoleted due to no activity on 2025/06/21 04:26
linux-6.1 BUG: unable to handle kernel paging request in gfs2_glock_dq (2) 8 1 66d 66d 0/3 upstream: reported on 2026/02/11 16:38
linux-6.1 BUG: unable to handle kernel paging request in gfs2_glock_dq 8 6 272d 272d 0/3 auto-obsoleted due to no activity on 2025/10/29 04:50

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=14337, sector=68719479080, nr_sectors = 8 limit=32768
Buffer I/O error on dev loop0, logical block 8589934885, lost async page write
syz.0.0: attempt to access beyond end of device
loop0: rw=14337, sector=68719479088, nr_sectors = 8 limit=32768
Buffer I/O error on dev loop0, logical block 8589934886, lost async page write
syz.0.0: attempt to access beyond end of device
loop0: rw=12288, sector=68719479080, nr_sectors = 8 limit=32768
Oops: general protection fault, probably for non-canonical address 0xdffffc0000000007: 0000 [#1] SMP KASAN NOPTI
KASAN: null-ptr-deref in range [0x0000000000000038-0x000000000000003f]
CPU: 0 UID: 0 PID: 5322 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:kasan_byte_accessible+0x12/0x30 mm/kasan/generic.c:210
Code: 79 ff ff ff 0f 1f 40 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 0f 1f 40 d6 48 c1 ef 03 48 b8 00 00 00 00 00 fc ff df <0f> b6 04 07 3c 08 0f 92 c0 e9 d0 ee 85 09 cc 66 66 66 66 66 66 2e
RSP: 0018:ffffc9000ef4fa70 EFLAGS: 00010202
RAX: dffffc0000000000 RBX: ffffffff8bb6cb1e RCX: 0000000080000002
RDX: 0000000000000000 RSI: ffffffff8bb6cb1e RDI: 0000000000000007
RBP: ffffffff841d5221 R08: 0000000000000001 R09: 0000000000000000
R10: dffffc0000000000 R11: ffffed100266c805 R12: 0000000000000000
R13: 0000000000000038 R14: 0000000000000038 R15: 0000000000000001
FS:  00007f02c583e6c0(0000) GS:ffff88808c832000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000200000000c80 CR3: 000000001f774000 CR4: 0000000000352ef0
Call Trace:
 <TASK>
 __kasan_check_byte+0x12/0x40 mm/kasan/common.c:573
 kasan_check_byte include/linux/kasan.h:402 [inline]
 lock_acquire+0x84/0x350 kernel/locking/lockdep.c:5842
 __raw_spin_lock include/linux/spinlock_api_smp.h:158 [inline]
 _raw_spin_lock+0x2e/0x40 kernel/locking/spinlock.c:158
 spin_lock include/linux/spinlock.h:342 [inline]
 gfs2_glock_dq+0xc1/0xb40 fs/gfs2/glock.c:1598
 gfs2_glock_dq_uninit+0x25/0xb0 fs/gfs2/glock.c:1656
 gfs2_seek_data+0x17d/0x250 fs/gfs2/inode.c:2243
 gfs2_llseek+0x1c1/0x270 fs/gfs2/file.c:75
 vfs_llseek fs/read_write.c:391 [inline]
 ksys_lseek fs/read_write.c:404 [inline]
 __do_sys_lseek fs/read_write.c:414 [inline]
 __se_sys_lseek fs/read_write.c:412 [inline]
 __x64_sys_lseek+0x14f/0x1e0 fs/read_write.c:412
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x15f/0xf80 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f02c499c819
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:00007f02c583dfe8 EFLAGS: 00000246 ORIG_RAX: 0000000000000008
RAX: ffffffffffffffda RBX: 00007f02c4c15fa0 RCX: 00007f02c499c819
RDX: 0000000000000003 RSI: 0000000000000004 RDI: 0000000000000006
RBP: 00007f02c4a32c91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f02c4c16038 R14: 00007f02c4c15fa0 R15: 00007ffe7c245c48
 </TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:kasan_byte_accessible+0x12/0x30 mm/kasan/generic.c:210
Code: 79 ff ff ff 0f 1f 40 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 0f 1f 40 d6 48 c1 ef 03 48 b8 00 00 00 00 00 fc ff df <0f> b6 04 07 3c 08 0f 92 c0 e9 d0 ee 85 09 cc 66 66 66 66 66 66 2e
RSP: 0018:ffffc9000ef4fa70 EFLAGS: 00010202
RAX: dffffc0000000000 RBX: ffffffff8bb6cb1e RCX: 0000000080000002
RDX: 0000000000000000 RSI: ffffffff8bb6cb1e RDI: 0000000000000007
RBP: ffffffff841d5221 R08: 0000000000000001 R09: 0000000000000000
R10: dffffc0000000000 R11: ffffed100266c805 R12: 0000000000000000
R13: 0000000000000038 R14: 0000000000000038 R15: 0000000000000001
FS:  00007f02c583e6c0(0000) GS:ffff88808c832000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000200000000c80 CR3: 000000001f774000 CR4: 0000000000352ef0
----------------
Code disassembly (best guess), 4 bytes skipped:
   0:	0f 1f 40 00          	nopl   0x0(%rax)
   4:	90                   	nop
   5:	90                   	nop
   6:	90                   	nop
   7:	90                   	nop
   8:	90                   	nop
   9:	90                   	nop
   a:	90                   	nop
   b:	90                   	nop
   c:	90                   	nop
   d:	90                   	nop
   e:	90                   	nop
   f:	90                   	nop
  10:	90                   	nop
  11:	90                   	nop
  12:	90                   	nop
  13:	90                   	nop
  14:	0f 1f 40 d6          	nopl   -0x2a(%rax)
  18:	48 c1 ef 03          	shr    $0x3,%rdi
  1c:	48 b8 00 00 00 00 00 	movabs $0xdffffc0000000000,%rax
  23:	fc ff df
* 26:	0f b6 04 07          	movzbl (%rdi,%rax,1),%eax <-- trapping instruction
  2a:	3c 08                	cmp    $0x8,%al
  2c:	0f 92 c0             	setb   %al
  2f:	e9 d0 ee 85 09       	jmp    0x985ef04
  34:	cc                   	int3
  35:	66                   	data16
  36:	66                   	data16
  37:	66                   	data16
  38:	66                   	data16
  39:	66                   	data16
  3a:	66                   	data16
  3b:	2e                   	cs

Crashes (22):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/04/16 20:17 upstream 1d51b370a0f8 4743f87d .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root general protection fault in gfs2_glock_dq
2026/04/04 10:45 upstream 631919fb12fe 4440e7c2 .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root general protection fault in gfs2_glock_dq
2026/04/04 00:47 upstream d8a9a4b11a13 4440e7c2 .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root general protection fault in gfs2_glock_dq
2026/03/26 10:32 upstream d2a43e7f89da c6143aac .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root general protection fault in gfs2_glock_dq
2026/03/23 18:13 upstream c369299895a5 4933dba2 .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root general protection fault in gfs2_glock_dq
2026/03/11 05:55 upstream b4f0dd314b39 86914af9 .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root general protection fault in gfs2_glock_dq
2026/03/09 11:21 upstream 1f318b96cc84 5cb44a80 .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root general protection fault in gfs2_glock_dq
2026/02/27 08:09 upstream 3f4a08e64442 a2f13f71 .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root general protection fault in gfs2_glock_dq
2026/02/15 21:43 upstream ca4ee40bf13d 1e62d198 .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root general protection fault in gfs2_glock_dq
2026/02/12 23:11 upstream 37a93dd5c49b 504cb1bf .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root general protection fault in gfs2_glock_dq
2026/02/09 14:53 upstream 05f7e89ab973 df949cd9 .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root general protection fault in gfs2_glock_dq
2026/02/09 13:18 upstream 05f7e89ab973 df949cd9 .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root general protection fault in gfs2_glock_dq
2026/02/07 05:03 upstream 2687c848e578 f20fc9f9 .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root general protection fault in gfs2_glock_dq
2026/01/17 07:27 upstream 54e82e93ca93 d1b870e1 .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root general protection fault in gfs2_glock_dq
2026/01/09 09:28 upstream 54e82e93ca93 d1b870e1 .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root general protection fault in gfs2_glock_dq
2026/01/09 08:38 upstream 54e82e93ca93 d1b870e1 .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root general protection fault in gfs2_glock_dq
2025/12/26 11:21 upstream ccd1cdca5cd4 d1b870e1 .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root general protection fault in gfs2_glock_dq
2025/12/19 10:48 upstream 516471569089 d1b870e1 .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root general protection fault in gfs2_glock_dq
2025/12/15 07:12 upstream 8f0b4cce4481 d1b870e1 .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root general protection fault in gfs2_glock_dq
2025/12/08 17:28 upstream c2f2b01b74be d1b870e1 .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root general protection fault in gfs2_glock_dq
2025/12/06 00:27 upstream d1d36025a617 d1b870e1 .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root general protection fault in gfs2_glock_dq
2025/12/28 15:30 linux-next cc3aa43b44bd d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-linux-next-kasan-gce-root general protection fault in gfs2_glock_dq
* Struck through repros no longer work on HEAD.