syzbot
general protection fault in raid5_quiesce
Status:
moderation: reported on 2026/10/02 10:59
Subsystems:
raid
Labels:
prio:low
[Documentation on labels]
Reported-by: syzbot+570c8b99baea81f6e97e@syzkaller.appspotmail.com
First crash: 4d05h, last: 4d05h
Sample crash report:
Oops: general protection fault, probably for non-canonical address 0xdffffc000000000c: 0000 [#1] SMP KASAN PTI
KASAN: null-ptr-deref in range [0x0000000000000060-0x0000000000000067]
CPU: 0 UID: 0 PID: 11285 Comm: syz.4.1557 Tainted: G L syzkaller #0 PREEMPT_{RT,(full)}
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
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 80 b0 29 09 cc 66 66 66 66 66 66 2e
RSP: 0018:ffffc90019cff708 EFLAGS: 00010206
RAX: dffffc0000000000 RBX: ffffffff8b5ad0e3 RCX: 8000000000000001
RDX: 0000000000000000 RSI: ffffffff8b5ad0e3 RDI: 000000000000000c
RBP: ffffc90019cff870 R08: 0000000000000001 R09: 0000000000000000
R10: dffffc0000000000 R11: ffffffff87fdad00 R12: 0000000000000060
R13: 0000000000000000 R14: 0000000000000060 R15: 0000000000000001
FS: 00007fcc1fc556c0(0000) GS:ffff888125bc4000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f5e73d16300 CR3: 000000005e1e4000 CR4: 00000000003526f0
Call Trace:
<TASK>
__kasan_check_byte+0x12/0x40 mm/kasan/common.c:573
kasan_check_byte include/linux/kasan.h:402 [inline]
lock_acquire+0x7d/0x350 kernel/locking/lockdep.c:5916
rt_spin_lock+0x83/0x400 kernel/locking/spinlock_rt.c:56
spin_lock_irq include/linux/spinlock_rt.h:96 [inline]
lock_all_device_hash_locks_irq drivers/md/raid5.c:107 [inline]
raid5_quiesce+0xc2/0x8a0 drivers/md/raid5.c:-1
__md_stop_writes+0xeb/0x4b0 drivers/md/md.c:7038
md_set_readonly+0x330/0x560 drivers/md/md.c:7138
array_state_store+0x584/0xe90 drivers/md/md.c:4720
md_attr_store+0x3b7/0x640 drivers/md/md.c:6158
kernfs_fop_write_iter+0x3a5/0x540 fs/kernfs/file.c:345
new_sync_write fs/read_write.c:595 [inline]
vfs_write+0x61e/0xbb0 fs/read_write.c:687
ksys_write+0x156/0x270 fs/read_write.c:739
do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
do_syscall_64+0x166/0x520 arch/x86/entry/syscall_64.c:84
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fcc21a1e159
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:00007fcc1fc55028 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007fcc21ca6090 RCX: 00007fcc21a1e159
RDX: 0000000000000008 RSI: 0000200000000c00 RDI: 0000000000000007
RBP: 00007fcc21ab506b R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fcc21ca6128 R14: 00007fcc21ca6090 R15: 00007ffd54d55a88
</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 80 b0 29 09 cc 66 66 66 66 66 66 2e
RSP: 0018:ffffc90019cff708 EFLAGS: 00010206
RAX: dffffc0000000000 RBX: ffffffff8b5ad0e3 RCX: 8000000000000001
RDX: 0000000000000000 RSI: ffffffff8b5ad0e3 RDI: 000000000000000c
RBP: ffffc90019cff870 R08: 0000000000000001 R09: 0000000000000000
R10: dffffc0000000000 R11: ffffffff87fdad00 R12: 0000000000000060
R13: 0000000000000000 R14: 0000000000000060 R15: 0000000000000001
FS: 00007fcc1fc556c0(0000) GS:ffff888125bc4000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fea63543480 CR3: 000000005e1e4000 CR4: 00000000003526f0
----------------
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 80 b0 29 09 jmp 0x929b0b4
34: cc int3
35: 66 data16
36: 66 data16
37: 66 data16
38: 66 data16
39: 66 data16
3a: 66 data16
3b: 2e cs
* Struck through repros no longer work on HEAD.