syzbot
general protection fault in ocfs2_prepare_dir_for_insert
Status:
upstream: reported C repro on 2025/12/18 19:22
Bug presence:
origin:lts-only
[Documentation on labels]
Reported-by: syzbot+958945cfbe7735cc63b6@syzkaller.appspotmail.com
First crash: 270d, last: 4d09h
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Bug presence (2)
| Date |
Name |
Commit |
Repro |
Result |
| 2025/12/19 |
linux-5.15.y (ToT) |
68efe5a6c16a |
C
|
[report] general protection fault in ocfs2_prepare_dir_for_insert
|
| 2025/12/19 |
upstream (ToT) |
dd9b004b7ff3 |
C
|
Didn't crash |
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Last patch testing requests (3)
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Fix bisection attempts (1)
| Created |
Duration |
User |
Patch |
Repo |
Result |
| 2026/01/07 01:39 |
1h44m
|
fix candidate
|
|
upstream |
OK
(0)
job log
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Sample crash report:
and is ignored by this kernel. Remove the mand
option from the mount to silence this warning.
=======================================================
JBD2: Ignoring recovery information on journal
ocfs2: Mounting device (7,0) on (node local, slot 0) with ordered data mode.
general protection fault, probably for non-canonical address 0xdffffc0000000001: 0000 [#1] PREEMPT SMP KASAN
KASAN: null-ptr-deref in range [0x0000000000000008-0x000000000000000f]
CPU: 0 PID: 4313 Comm: syz.0.17 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
RIP: 0010:ocfs2_find_dir_space_id fs/ocfs2/dir.c:3425 [inline]
RIP: 0010:ocfs2_prepare_dir_for_insert+0x2e54/0x52b0 fs/ocfs2/dir.c:4305
Code: ff ff e8 3f f7 57 fe e9 38 01 00 00 e8 35 f7 57 fe 49 bc 00 00 00 00 00 fc ff df 49 8d 7d 08 49 8d 5d 09 48 89 f8 48 c1 e8 03 <42> 0f b6 04 20 84 c0 0f 85 6a 1f 00 00 4c 8b 74 24 70 4c 2b 74 24
RSP: 0018:ffffc9000311f080 EFLAGS: 00010202
RAX: 0000000000000001 RBX: 0000000000000009 RCX: ffff888021881dc0
RDX: 0000000000000000 RSI: ffff88807d0c20c8 RDI: 0000000000000008
RBP: ffffc9000311f7b0 R08: ffffc9000311fac0 R09: 0000000000000002
R10: 0000000000000002 R11: 0000000000000000 R12: dffffc0000000000
R13: 0000000000000000 R14: ffff88807c8200f8 R15: ffff88805bcfddf8
FS: 000055558c53d500(0000) GS:ffff8880b9000000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b31863fff CR3: 00000000749d1000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
<TASK>
__ocfs2_prepare_orphan_dir+0x141/0x310 fs/ocfs2/namei.c:2164
ocfs2_prepare_orphan_dir+0xed/0x410 fs/ocfs2/namei.c:2207
ocfs2_unlink+0xb61/0x1980 fs/ocfs2/namei.c:959
vfs_unlink+0x376/0x600 fs/namei.c:4331
do_unlinkat+0x391/0x710 fs/namei.c:4399
__do_sys_unlink fs/namei.c:4447 [inline]
__se_sys_unlink fs/namei.c:4445 [inline]
__x64_sys_unlink+0x45/0x50 fs/namei.c:4445
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: 0033:0x7f985ba75159
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:00007fffd5c22e98 EFLAGS: 00000246 ORIG_RAX: 0000000000000057
RAX: ffffffffffffffda RBX: 00007f985bcfcfa0 RCX: 00007f985ba75159
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000200000000040
RBP: 00007f985bb0c03b R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f985bcfcfac R14: 00007f985bcfcfa0 R15: 00007f985bcfcfa0
</TASK>
Modules linked in:
---[ end trace 78c967667a9653af ]---
RIP: 0010:ocfs2_find_dir_space_id fs/ocfs2/dir.c:3425 [inline]
RIP: 0010:ocfs2_prepare_dir_for_insert+0x2e54/0x52b0 fs/ocfs2/dir.c:4305
Code: ff ff e8 3f f7 57 fe e9 38 01 00 00 e8 35 f7 57 fe 49 bc 00 00 00 00 00 fc ff df 49 8d 7d 08 49 8d 5d 09 48 89 f8 48 c1 e8 03 <42> 0f b6 04 20 84 c0 0f 85 6a 1f 00 00 4c 8b 74 24 70 4c 2b 74 24
RSP: 0018:ffffc9000311f080 EFLAGS: 00010202
RAX: 0000000000000001 RBX: 0000000000000009 RCX: ffff888021881dc0
RDX: 0000000000000000 RSI: ffff88807d0c20c8 RDI: 0000000000000008
RBP: ffffc9000311f7b0 R08: ffffc9000311fac0 R09: 0000000000000002
R10: 0000000000000002 R11: 0000000000000000 R12: dffffc0000000000
R13: 0000000000000000 R14: ffff88807c8200f8 R15: ffff88805bcfddf8
FS: 000055558c53d500(0000) GS:ffff8880b9100000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f7d84893000 CR3: 00000000749d1000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
----------------
Code disassembly (best guess), 1 bytes skipped:
0: ff ljmp (bad)
1: e8 3f f7 57 fe call 0xfe57f745
6: e9 38 01 00 00 jmp 0x143
b: e8 35 f7 57 fe call 0xfe57f745
10: 49 bc 00 00 00 00 00 movabs $0xdffffc0000000000,%r12
17: fc ff df
1a: 49 8d 7d 08 lea 0x8(%r13),%rdi
1e: 49 8d 5d 09 lea 0x9(%r13),%rbx
22: 48 89 f8 mov %rdi,%rax
25: 48 c1 e8 03 shr $0x3,%rax
* 29: 42 0f b6 04 20 movzbl (%rax,%r12,1),%eax <-- trapping instruction
2e: 84 c0 test %al,%al
30: 0f 85 6a 1f 00 00 jne 0x1fa0
36: 4c 8b 74 24 70 mov 0x70(%rsp),%r14
3b: 4c rex.WR
3c: 2b .byte 0x2b
3d: 74 24 je 0x63
Struck through repros no longer work on HEAD.