[syzbot] [btrfs?] general protection fault in detach_extent_buffer_folio (2)

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: d358e5254674 Merge tag 'for-6.19/dm-changes' of git://git...
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=132e161a580000
kernel config: https://syzkaller.appspot.com/x/.config?x=de48dccdf203ea90
dashboard link: https://syzkaller.appspot.com/bug?extid=f0d57fef86e1112b6b37
compiler: Debian clang version 20.1.8 (++20250708063551+0c9f909b7976-1~exp1~20250708183702.136), Debian LLD 20.1.8

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

Downloadable assets:
disk image (non-bootable): https://storage.googleapis.com/syzbot-assets/d900f083ada3/non_bootable_disk-d358e525.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/3fa1d04c1a85/vmlinux-d358e525.xz
kernel image: https://storage.googleapis.com/syzbot-assets/a9b253146e36/bzImage-d358e525.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+f0d57f...@syzkaller.appspotmail.com

BTRFS info (device loop0): balance: start -d -m
BTRFS info (device loop0): relocating block group 6881280 flags data|metadata
BTRFS info (device loop0): relocating block group 5242880 flags data|metadata
Oops: general protection fault, probably for non-canonical address 0xdffffc000000002a: 0000 [#1] SMP KASAN NOPTI
KASAN: null-ptr-deref in range [0x0000000000000150-0x0000000000000157]
CPU: 0 UID: 0 PID: 5340 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~bpo12+1 04/01/2014
RIP: 0010:kasan_byte_accessible+0x12/0x30 mm/kasan/generic.c:210
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 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 c3 cc cc cc cc cc 66 66 66 66 66 66 2e
RSP: 0018:ffffc900099bef98 EFLAGS: 00010202
RAX: dffffc0000000000 RBX: ffffffff8b5f9b4e RCX: 941b0e0fd311fb00
RDX: 0000000000000000 RSI: ffffffff8b5f9b4e RDI: 000000000000002a
RBP: ffffffff83dbedcc R08: 0000000000000001 R09: 0000000000000000
R10: dffffc0000000000 R11: ffffed10022e803f R12: 0000000000000000
R13: 0000000000000150 R14: 0000000000000150 R15: 0000000000000001
FS: 00007f3e987896c0(0000) GS:ffff88808d22f000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f98d1067bc0 CR3: 000000001eed1000 CR4: 0000000000352ef0
Call Trace:
<TASK>
__kasan_check_byte+0x12/0x40 mm/kasan/common.c:572
kasan_check_byte include/linux/kasan.h:401 [inline]
lock_acquire+0x84/0x340 kernel/locking/lockdep.c:5842
__raw_spin_lock include/linux/spinlock_api_smp.h:133 [inline]
_raw_spin_lock+0x2e/0x40 kernel/locking/spinlock.c:154
spin_lock include/linux/spinlock.h:351 [inline]
detach_extent_buffer_folio+0xdc/0x730 fs/btrfs/extent_io.c:2909
btrfs_release_extent_buffer_folios+0xc9/0x4b0 fs/btrfs/extent_io.c:2969
release_extent_buffer+0x16b/0x240 fs/btrfs/extent_io.c:3618
btrfs_force_cow_block+0x10d6/0x2410 fs/btrfs/ctree.c:605
btrfs_cow_block+0x3c4/0xa80 fs/btrfs/ctree.c:708
do_relocation+0xc0b/0x17c0 fs/btrfs/relocation.c:2287
relocate_tree_block fs/btrfs/relocation.c:2540 [inline]
relocate_tree_blocks+0x11c3/0x1fa0 fs/btrfs/relocation.c:2647
relocate_block_group+0x76e/0xd70 fs/btrfs/relocation.c:3573
btrfs_relocate_block_group+0x6b6/0xc70 fs/btrfs/relocation.c:3966
btrfs_relocate_chunk+0x12f/0x5c0 fs/btrfs/volumes.c:3424
__btrfs_balance+0x18ff/0x24e0 fs/btrfs/volumes.c:4197
btrfs_balance+0xac2/0x11b0 fs/btrfs/volumes.c:4571
btrfs_ioctl_balance+0x3d3/0x610 fs/btrfs/ioctl.c:3525
vfs_ioctl fs/ioctl.c:51 [inline]
__do_sys_ioctl fs/ioctl.c:597 [inline]
__se_sys_ioctl+0xfc/0x170 fs/ioctl.c:583
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xfa/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f3e9798f7c9
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 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 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f3e98789038 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007f3e97be6090 RCX: 00007f3e9798f7c9
RDX: 0000200000000180 RSI: 00000000c4009420 RDI: 0000000000000004
RBP: 00007f3e97a13f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f3e97be6128 R14: 00007f3e97be6090 R15: 00007ffc12b96d88
</TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:kasan_byte_accessible+0x12/0x30 mm/kasan/generic.c:210
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 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 c3 cc cc cc cc cc 66 66 66 66 66 66 2e
RSP: 0018:ffffc900099bef98 EFLAGS: 00010202
RAX: dffffc0000000000 RBX: ffffffff8b5f9b4e RCX: 941b0e0fd311fb00
RDX: 0000000000000000 RSI: ffffffff8b5f9b4e RDI: 000000000000002a
RBP: ffffffff83dbedcc R08: 0000000000000001 R09: 0000000000000000
R10: dffffc0000000000 R11: ffffed10022e803f R12: 0000000000000000
R13: 0000000000000150 R14: 0000000000000150 R15: 0000000000000001
FS: 00007f3e987896c0(0000) GS:ffff88808d22f000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f98d1067bc0 CR3: 000000001eed1000 CR4: 0000000000352ef0
----------------
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: 0f 1f 40 d6 nopl -0x2a(%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: cc int3
39: 66 data16
3a: 66 data16
3b: 66 data16
3c: 66 data16
3d: 66 data16
3e: 66 data16
3f: 2e cs


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