[moderation] [bcachefs?] general protection fault in closure_put_after_sub (3)

Hello,

syzbot found the following issue on:

HEAD commit: acb4f33713b9 Merge tag 'm68knommu-for-v6.15' of git://git...
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=1462c678580000
kernel config: https://syzkaller.appspot.com/x/.config?x=982413b40f90fdf8
dashboard link: https://syzkaller.appspot.com/bug?extid=8b760fe021b2b548c810
compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40
CC: [[email protected] [email protected] [email protected]]

Unfortunately, I don't have any reproducer for this issue yet.

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/29801dcd72c7/disk-acb4f337.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/606dd80a4b3e/vmlinux-acb4f337.xz
kernel image: https://storage.googleapis.com/syzbot-assets/acf6a9bb497d/bzImage-acb4f337.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: [email protected]

Oops: general protection fault, probably for non-canonical address 0xed001bfff1100364: 0000 [#1] SMP KASAN PTI
KASAN: maybe wild-memory-access in range [0x6800ffff88801b20-0x6800ffff88801b27]
CPU: 0 UID: 0 PID: 42 Comm: kworker/0:1H Not tainted 6.14.0-syzkaller-07422-gacb4f33713b9 #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
Workqueue: bcachefs_btree_io btree_node_write_work
RIP: 0010:kasan_byte_accessible+0x12/0x20 mm/kasan/generic.c:199
Code: 0f 1f 84 00 00 00 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 66 0f 1f 00 48 c1 ef 03 48 b8 00 00 00 00 00 fc ff df <0f> b6 04 07 3c 08 0f 92 c0 c3 cc cc cc cc 90 90 90 90 90 90 90 90
RSP: 0018:ffffc90000b375d0 EFLAGS: 00010002
RAX: dffffc0000000000 RBX: 6800ffff88801b22 RCX: 0000000000000000
RDX: 0000000000000000 RSI: ffffffff8c1fd56e RDI: 0d001ffff1100364
RBP: ffffffff935f9020 R08: 0000000000000001 R09: 0000000000000000
R10: dffffc0000000000 R11: ffffed100f473401 R12: 0000000000000001
R13: 0000000000000000 R14: ffffffff8c1fd56e R15: 6800ffff88801b22
FS: 0000000000000000(0000) GS:ffff888125027000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000110f27eb87 CR3: 000000006001e000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
<TASK>
__kasan_check_byte+0x14/0x40 mm/kasan/common.c:556
kasan_check_byte include/linux/kasan.h:399 [inline]
lock_acquire+0x89/0x2f0 kernel/locking/lockdep.c:5840
__raw_spin_lock include/linux/spinlock_api_smp.h:133 [inline]
_raw_spin_lock+0x2e/0x40 kernel/locking/spinlock.c:154
__queue_work+0x785/0x10a0 kernel/workqueue.c:-1
queue_work_on+0x1c4/0x380 kernel/workqueue.c:2392
queue_work include/linux/workqueue.h:662 [inline]
closure_queue include/linux/closure.h:268 [inline]
closure_put_after_sub+0x2b1/0x330 lib/closure.c:42
bch2_btree_complete_write fs/bcachefs/btree_io.c:2019 [inline]
__btree_node_write_done+0x258/0x460 fs/bcachefs/btree_io.c:2030
btree_node_write_done fs/bcachefs/btree_io.c:2073 [inline]
btree_node_write_work+0xacb/0xcc0 fs/bcachefs/btree_io.c:2116
process_one_work kernel/workqueue.c:3238 [inline]
process_scheduled_works+0xac3/0x18e0 kernel/workqueue.c:3319
worker_thread+0x870/0xd50 kernel/workqueue.c:3400
kthread+0x7b7/0x940 kernel/kthread.c:464
ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:153
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
</TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:kasan_byte_accessible+0x12/0x20 mm/kasan/generic.c:199
Code: 0f 1f 84 00 00 00 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 66 0f 1f 00 48 c1 ef 03 48 b8 00 00 00 00 00 fc ff df <0f> b6 04 07 3c 08 0f 92 c0 c3 cc cc cc cc 90 90 90 90 90 90 90 90
RSP: 0018:ffffc90000b375d0 EFLAGS: 00010002
RAX: dffffc0000000000 RBX: 6800ffff88801b22 RCX: 0000000000000000
RDX: 0000000000000000 RSI: ffffffff8c1fd56e RDI: 0d001ffff1100364
RBP: ffffffff935f9020 R08: 0000000000000001 R09: 0000000000000000
R10: dffffc0000000000 R11: ffffed100f473401 R12: 0000000000000001
R13: 0000000000000000 R14: ffffffff8c1fd56e R15: 6800ffff88801b22
FS: 0000000000000000(0000) GS:ffff888125027000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000110f27eb87 CR3: 000000006001e000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
----------------
Code disassembly (best guess):
0: 0f 1f 84 00 00 00 00 nopl 0x0(%rax,%rax,1)
7: 00
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: 90 nop
15: 90 nop
16: 90 nop
17: 90 nop
18: 66 0f 1f 00 nopw (%rax)
1c: 48 c1 ef 03 shr $0x3,%rdi
20: 48 b8 00 00 00 00 00 movabs $0xdffffc0000000000,%rax
27: fc ff df
* 2a: 0f b6 04 07 movzbl (%rdi,%rax,1),%eax <-- trapping instruction
2e: 3c 08 cmp $0x8,%al
30: 0f 92 c0 setb %al
33: c3 ret
34: cc int3
35: cc int3
36: cc int3
37: cc int3
38: 90 nop
39: 90 nop
3a: 90 nop
3b: 90 nop
3c: 90 nop
3d: 90 nop
3e: 90 nop
3f: 90 nop


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