[syzbot] [btrfs?] general protection fault in btrfs_evict_inode

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: f406055cb18c Merge tag 'arm64-fixes' of git://git.kernel.o..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=12a1b52f980000
kernel config: https://syzkaller.appspot.com/x/.config?x=c2d7b4143707d3a0
dashboard link: https://syzkaller.appspot.com/bug?extid=d991fea1b4b23b1f6bf8
compiler: Debian clang version 20.1.8 (++20250708063551+0c9f909b7976-1~exp1~20250708183702.136), Debian LLD 20.1.8
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=1430f67c580000

Downloadable assets:
disk image (non-bootable): https://storage.googleapis.com/syzbot-assets/d900f083ada3/non_bootable_disk-f406055c.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/c7e9d41abcc8/vmlinux-f406055c.xz
kernel image: https://storage.googleapis.com/syzbot-assets/545562cd43ff/bzImage-f406055c.xz
mounted in repro: https://storage.googleapis.com/syzbot-assets/ed6f0c604e16/mount_2.gz
fsck result: OK (log: https://syzkaller.appspot.com/x/fsck.log?x=1087e734580000)

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+d991fe...@syzkaller.appspotmail.com

BTRFS info (device loop0): turning on async discard
BTRFS info (device loop0): enabling free space tree
Oops: general protection fault, probably for non-canonical address 0xdffffc000000003e: 0000 [#1] SMP KASAN NOPTI
KASAN: null-ptr-deref in range [0x00000000000001f0-0x00000000000001f7]
CPU: 0 UID: 0 PID: 5682 Comm: syz.0.17 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:btrfs_root_id fs/btrfs/ctree.h:333 [inline]
RIP: 0010:do_perf_trace_btrfs__inode include/trace/events/btrfs.h:204 [inline]
RIP: 0010:perf_trace_btrfs__inode+0x44d/0x580 include/trace/events/btrfs.h:204
Code: c1 e8 03 42 80 3c 30 00 74 08 4c 89 ff e8 5b 44 66 fe 4d 8b 2f 4d 8d bd f7 01 00 00 49 81 c5 fe 01 00 00 4c 89 f8 48 c1 e8 03 <42> 0f b6 04 30 84 c0 0f 85 e4 00 00 00 4c 89 e8 48 c1 e8 03 42 0f
RSP: 0018:ffffc9000d246d60 EFLAGS: 00010203
RAX: 000000000000003e RBX: ffffe8ffffc990a0 RCX: ffffffff83c14767
RDX: 0000000000000010 RSI: ffff888058fd0400 RDI: ffffe8ffffc99068
RBP: ffffc9000d246e30 R08: e443157bdb42d614 R09: f8256aac8f4be681
R10: e443157bdb42d614 R11: f8256aac8f4be681 R12: ffffe8ffffc99060
R13: 00000000000001fe R14: dffffc0000000000 R15: 00000000000001f7
FS: 00007fa645d796c0(0000) GS:ffff88808d300000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000056106e704950 CR3: 000000003f1ca000 CR4: 0000000000352ef0
Call Trace:
<TASK>
__do_trace_btrfs_inode_evict include/trace/events/btrfs.h:255 [inline]
trace_btrfs_inode_evict include/trace/events/btrfs.h:255 [inline]
btrfs_evict_inode+0x107a/0x1110 fs/btrfs/inode.c:5480
evict+0x504/0x9c0 fs/inode.c:810
btrfs_rename fs/btrfs/inode.c:8640 [inline]
btrfs_rename2+0x264f/0x3fd0 fs/btrfs/inode.c:8660
vfs_rename+0xb34/0xe80 fs/namei.c:5216
ovl_do_rename fs/overlayfs/overlayfs.h:373 [inline]
ovl_check_rename_whiteout fs/overlayfs/super.c:595 [inline]
ovl_make_workdir fs/overlayfs/super.c:714 [inline]
ovl_get_workdir+0x846/0x17b0 fs/overlayfs/super.c:837
ovl_fill_super+0x154a/0x3da0 fs/overlayfs/super.c:1468
vfs_get_super fs/super.c:1324 [inline]
get_tree_nodev+0xbb/0x150 fs/super.c:1343
vfs_get_tree+0x92/0x2b0 fs/super.c:1751
fc_mount fs/namespace.c:1208 [inline]
do_new_mount_fc fs/namespace.c:3651 [inline]
do_new_mount+0x302/0xa10 fs/namespace.c:3727
do_mount fs/namespace.c:4050 [inline]
__do_sys_mount fs/namespace.c:4238 [inline]
__se_sys_mount+0x313/0x410 fs/namespace.c:4215
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xfa/0xfa0 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fa644f8efc9
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:00007fa645d79038 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00007fa6451e5fa0 RCX: 00007fa644f8efc9
RDX: 0000200000000b80 RSI: 0000200000000000 RDI: 0000000000000000
RBP: 00007fa645011f91 R08: 0000200000000780 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fa6451e6038 R14: 00007fa6451e5fa0 R15: 00007ffdeeb9aa68
</TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:btrfs_root_id fs/btrfs/ctree.h:333 [inline]
RIP: 0010:do_perf_trace_btrfs__inode include/trace/events/btrfs.h:204 [inline]
RIP: 0010:perf_trace_btrfs__inode+0x44d/0x580 include/trace/events/btrfs.h:204
Code: c1 e8 03 42 80 3c 30 00 74 08 4c 89 ff e8 5b 44 66 fe 4d 8b 2f 4d 8d bd f7 01 00 00 49 81 c5 fe 01 00 00 4c 89 f8 48 c1 e8 03 <42> 0f b6 04 30 84 c0 0f 85 e4 00 00 00 4c 89 e8 48 c1 e8 03 42 0f
RSP: 0018:ffffc9000d246d60 EFLAGS: 00010203
RAX: 000000000000003e RBX: ffffe8ffffc990a0 RCX: ffffffff83c14767
RDX: 0000000000000010 RSI: ffff888058fd0400 RDI: ffffe8ffffc99068
RBP: ffffc9000d246e30 R08: e443157bdb42d614 R09: f8256aac8f4be681
R10: e443157bdb42d614 R11: f8256aac8f4be681 R12: ffffe8ffffc99060
R13: 00000000000001fe R14: dffffc0000000000 R15: 00000000000001f7
FS: 00007fa645d796c0(0000) GS:ffff88808d300000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000056106e704950 CR3: 000000003f1ca000 CR4: 0000000000352ef0
----------------
Code disassembly (best guess):
0: c1 e8 03 shr $0x3,%eax
3: 42 80 3c 30 00 cmpb $0x0,(%rax,%r14,1)
8: 74 08 je 0x12
a: 4c 89 ff mov %r15,%rdi
d: e8 5b 44 66 fe call 0xfe66446d
12: 4d 8b 2f mov (%r15),%r13
15: 4d 8d bd f7 01 00 00 lea 0x1f7(%r13),%r15
1c: 49 81 c5 fe 01 00 00 add $0x1fe,%r13
23: 4c 89 f8 mov %r15,%rax
26: 48 c1 e8 03 shr $0x3,%rax
* 2a: 42 0f b6 04 30 movzbl (%rax,%r14,1),%eax <-- trapping instruction
2f: 84 c0 test %al,%al
31: 0f 85 e4 00 00 00 jne 0x11b
37: 4c 89 e8 mov %r13,%rax
3a: 48 c1 e8 03 shr $0x3,%rax
3e: 42 rex.X
3f: 0f .byte 0xf


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