syzbot


general protection fault in ocfs2_assure_trans_credits (2)

Status: moderation: reported on 2026/02/15 08:27
Subsystems: ocfs2
[Documentation on labels]
Reported-by: syzbot+db62c97b96f1adb25d45@syzkaller.appspotmail.com
First crash: 6d13h, last: 5d23h
Similar bugs (1)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream general protection fault in ocfs2_assure_trans_credits ocfs2 2 C 22 158d 316d 0/29 auto-obsoleted due to no activity on 2025/12/21 09:01

Sample crash report:
(syz.0.0,5319,0):ocfs2_extend_trans:460 ERROR: status = -30
(syz.0.0,5319,0):ocfs2_try_to_merge_extent:3817 ERROR: status = -30
Oops: general protection fault, probably for non-canonical address 0xdffffc0000000000: 0000 [#1] SMP KASAN NOPTI
KASAN: null-ptr-deref in range [0x0000000000000000-0x0000000000000007]
CPU: 0 UID: 0 PID: 5319 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:jbd2_handle_buffer_credits include/linux/jbd2.h:-1 [inline]
RIP: 0010:ocfs2_assure_trans_credits+0x7d/0x350 fs/ocfs2/journal.c:479
Code: 4c 89 f0 48 c1 e8 03 42 80 3c 28 00 74 08 4c 89 f7 e8 97 a6 73 fe 4d 8b 3e eb 08 e8 8d ec 08 fe 4d 89 f7 4c 89 f8 48 c1 e8 03 <42> 80 3c 28 00 74 08 4c 89 ff e8 74 a6 73 fe 4d 8b 3f 49 8d 7e 10
RSP: 0018:ffffc9000e7eeca8 EFLAGS: 00010246
RAX: 0000000000000000 RBX: 000000000000000a RCX: 0000000000100000
RDX: ffffc90020031000 RSI: 0000000000049cb5 RDI: 0000000000049cb6
RBP: 0000000000000000 R08: ffff888035960000 R09: 0000000000000006
R10: 00000000fffffffc R11: 0000000000000002 R12: ffff88805700fbb0
R13: dffffc0000000000 R14: ffff88805700fbb0 R15: 0000000000000000
FS:  00007fb50247c6c0(0000) GS:ffff88808cabd000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00002000000ae000 CR3: 000000003815f000 CR4: 0000000000352ef0
Call Trace:
 <TASK>
 ocfs2_dio_end_io_write fs/ocfs2/aops.c:2345 [inline]
 ocfs2_dio_end_io+0xbb5/0x1210 fs/ocfs2/aops.c:2404
 dio_complete+0x25b/0x790 fs/direct-io.c:281
 __blockdev_direct_IO+0x2cb0/0x32f0 fs/direct-io.c:1303
 ocfs2_direct_IO+0x251/0x2c0 fs/ocfs2/aops.c:2441
 generic_file_direct_write+0x1db/0x3e0 mm/filemap.c:4248
 __generic_file_write_iter+0x11d/0x230 mm/filemap.c:4417
 ocfs2_file_write_iter+0x1663/0x1e20 fs/ocfs2/file.c:2476
 iter_file_splice_write+0x99b/0x1100 fs/splice.c:738
 do_splice_from fs/splice.c:938 [inline]
 direct_splice_actor+0x101/0x160 fs/splice.c:1161
 splice_direct_to_actor+0x53a/0xc70 fs/splice.c:1105
 do_splice_direct_actor fs/splice.c:1204 [inline]
 do_splice_direct+0x195/0x290 fs/splice.c:1230
 do_sendfile+0x535/0x7d0 fs/read_write.c:1372
 __do_sys_sendfile64 fs/read_write.c:1433 [inline]
 __se_sys_sendfile64+0x144/0x1a0 fs/read_write.c:1419
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x14d/0xf80 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fb50159bf79
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:00007fb50247c028 EFLAGS: 00000246 ORIG_RAX: 0000000000000028
RAX: ffffffffffffffda RBX: 00007fb501816090 RCX: 00007fb50159bf79
RDX: 0000000000000000 RSI: 0000000000000005 RDI: 0000000000000006
RBP: 00007fb5016327e0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000080000002 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fb501816128 R14: 00007fb501816090 R15: 00007ffc8d0afe38
 </TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:jbd2_handle_buffer_credits include/linux/jbd2.h:-1 [inline]
RIP: 0010:ocfs2_assure_trans_credits+0x7d/0x350 fs/ocfs2/journal.c:479
Code: 4c 89 f0 48 c1 e8 03 42 80 3c 28 00 74 08 4c 89 f7 e8 97 a6 73 fe 4d 8b 3e eb 08 e8 8d ec 08 fe 4d 89 f7 4c 89 f8 48 c1 e8 03 <42> 80 3c 28 00 74 08 4c 89 ff e8 74 a6 73 fe 4d 8b 3f 49 8d 7e 10
RSP: 0018:ffffc9000e7eeca8 EFLAGS: 00010246
RAX: 0000000000000000 RBX: 000000000000000a RCX: 0000000000100000
RDX: ffffc90020031000 RSI: 0000000000049cb5 RDI: 0000000000049cb6
RBP: 0000000000000000 R08: ffff888035960000 R09: 0000000000000006
R10: 00000000fffffffc R11: 0000000000000002 R12: ffff88805700fbb0
R13: dffffc0000000000 R14: ffff88805700fbb0 R15: 0000000000000000
FS:  00007fb50247c6c0(0000) GS:ffff88808cabd000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055b7cfd3f168 CR3: 000000003815f000 CR4: 0000000000352ef0
----------------
Code disassembly (best guess):
   0:	4c 89 f0             	mov    %r14,%rax
   3:	48 c1 e8 03          	shr    $0x3,%rax
   7:	42 80 3c 28 00       	cmpb   $0x0,(%rax,%r13,1)
   c:	74 08                	je     0x16
   e:	4c 89 f7             	mov    %r14,%rdi
  11:	e8 97 a6 73 fe       	call   0xfe73a6ad
  16:	4d 8b 3e             	mov    (%r14),%r15
  19:	eb 08                	jmp    0x23
  1b:	e8 8d ec 08 fe       	call   0xfe08ecad
  20:	4d 89 f7             	mov    %r14,%r15
  23:	4c 89 f8             	mov    %r15,%rax
  26:	48 c1 e8 03          	shr    $0x3,%rax
* 2a:	42 80 3c 28 00       	cmpb   $0x0,(%rax,%r13,1) <-- trapping instruction
  2f:	74 08                	je     0x39
  31:	4c 89 ff             	mov    %r15,%rdi
  34:	e8 74 a6 73 fe       	call   0xfe73a6ad
  39:	4d 8b 3f             	mov    (%r15),%r15
  3c:	49 8d 7e 10          	lea    0x10(%r14),%rdi

Crashes (3):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/02/11 21:57 upstream 192c0159402e 75707236 .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root general protection fault in ocfs2_assure_trans_credits
2026/02/11 08:24 upstream dc855b77719f 441e25b7 .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root general protection fault in ocfs2_assure_trans_credits
2026/02/11 08:19 upstream dc855b77719f 441e25b7 .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root general protection fault in ocfs2_assure_trans_credits
* Struck through repros no longer work on HEAD.