[moderation] [btrfs?] general protection fault in detach_extent_buffer_folio (3)

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 3036cd0d3328 Merge tag 'ata-7.0-final' of git://git.kernel..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=157db126580000
kernel config: https://syzkaller.appspot.com/x/.config?x=d46eab0cfd31c214
dashboard link: https://syzkaller.appspot.com/bug?extid=513d3e89d6cd9be3c461
compiler: Debian clang version 21.1.8 (++20251221033036+2078da43e25a-1~exp1~20251221153213.50), Debian LLD 21.1.8
CC: [c...@fb.com dst...@suse.com linux...@vger.kernel.org linux-...@vger.kernel.org]

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-3036cd0d.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/52b4694b61e7/vmlinux-3036cd0d.xz
kernel image: https://storage.googleapis.com/syzbot-assets/3cae4a12f2ba/bzImage-3036cd0d.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+513d3e...@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
BTRFS info (device loop0): found 14 extents, stage: move data extents
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: 5321 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: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 c3 cc cc cc cc cc 66 66 66 66 66 66 2e
RSP: 0018:ffffc9000db5ebc8 EFLAGS: 00010202
RAX: dffffc0000000000 RBX: ffffffff8bb45e1e RCX: 0000000080000002
RDX: 0000000000000000 RSI: ffffffff8bb45e1e RDI: 000000000000002a
RBP: 0000000000000000 R08: 0000000000000001 R09: 0000000000000000
R10: dffffc0000000000 R11: ffffed100235ed2f R12: 0000000000000000
R13: 0000000000000150 R14: 0000000000000150 R15: 0000000000000001
FS: 00007f50d7df56c0(0000) GS:ffff88808ca49000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000564e8ad7a168 CR3: 000000001cda7000 CR4: 0000000000352ef0
Call Trace:
<TASK>
__kasan_check_byte+0x12/0x40 mm/kasan/common.c:573
kasan_check_byte include/linux/kasan.h:402 [inline]
lock_acquire+0x79/0x2e0 kernel/locking/lockdep.c:5842
__raw_spin_lock include/linux/spinlock_api_smp.h:158 [inline]
_raw_spin_lock+0x2e/0x40 kernel/locking/spinlock.c:154
spin_lock include/linux/spinlock.h:341 [inline]
detach_extent_buffer_folio+0xda/0x910 fs/btrfs/extent_io.c:2940
btrfs_release_extent_buffer_folios+0x68/0x440 fs/btrfs/extent_io.c:3000
release_extent_buffer+0x16b/0x240 fs/btrfs/extent_io.c:3649
free_extent_buffer+0x399/0x3f0 fs/btrfs/extent_io.c:3695
btrfs_del_items+0xb0c/0xd50 fs/btrfs/ctree.c:-1
__btrfs_free_extent+0x1275/0x4570 fs/btrfs/extent-tree.c:3546
run_delayed_tree_ref fs/btrfs/extent-tree.c:1824 [inline]
run_one_delayed_ref fs/btrfs/extent-tree.c:1851 [inline]
btrfs_run_delayed_refs_for_head fs/btrfs/extent-tree.c:2058 [inline]
__btrfs_run_delayed_refs+0x1881/0x4780 fs/btrfs/extent-tree.c:2133
btrfs_run_delayed_refs+0xe6/0x3b0 fs/btrfs/extent-tree.c:2245
btrfs_commit_transaction+0x29a/0x31a0 fs/btrfs/transaction.c:2254
relocate_block_group+0xcf9/0xe90 fs/btrfs/relocation.c:3653
do_nonremap_reloc+0xa8/0x5b0 fs/btrfs/relocation.c:5258
btrfs_relocate_block_group+0x75e/0xbc0 fs/btrfs/relocation.c:5424
btrfs_relocate_chunk+0x115/0x820 fs/btrfs/volumes.c:3590
__btrfs_balance+0x1db0/0x2ae0 fs/btrfs/volumes.c:4501
btrfs_balance+0xafa/0x11f0 fs/btrfs/volumes.c:4888
btrfs_ioctl_balance+0x3d3/0x610 fs/btrfs/ioctl.c:3452
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+0x14d/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f50db99c819
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:00007f50d7df4fe8 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007f50dbc16090 RCX: 00007f50db99c819
RDX: 0000200000000180 RSI: 00000000c4009420 RDI: 0000000000000007
RBP: 00007f50dba32c91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f50dbc16128 R14: 00007f50dbc16090 R15: 00007fff6c889198
</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 c3 cc cc cc cc cc 66 66 66 66 66 66 2e
RSP: 0018:ffffc9000db5ebc8 EFLAGS: 00010202
RAX: dffffc0000000000 RBX: ffffffff8bb45e1e RCX: 0000000080000002
RDX: 0000000000000000 RSI: ffffffff8bb45e1e RDI: 000000000000002a
RBP: 0000000000000000 R08: 0000000000000001 R09: 0000000000000000
R10: dffffc0000000000 R11: ffffed100235ed2f R12: 0000000000000000
R13: 0000000000000150 R14: 0000000000000150 R15: 0000000000000001
FS: 00007f50d7df56c0(0000) GS:ffff88808ca49000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000564e8ad7a168 CR3: 000000001cda7000 CR4: 0000000000352ef0
----------------
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: c3 ret
30: cc int3
31: cc int3
32: cc int3
33: cc int3
34: cc int3
35: 66 data16
36: 66 data16
37: 66 data16
38: 66 data16
39: 66 data16
3a: 66 data16
3b: 2e cs


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