[v6.1] BUG: unable to handle kernel paging request in udf_fiiter_write_fi

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 58485ff1a74f Linux 6.1.141
git tree: linux-6.1.y
console output: https://syzkaller.appspot.com/x/log.txt?x=1139720c580000
kernel config: https://syzkaller.appspot.com/x/.config?x=d93c21c25e641edc
dashboard link: https://syzkaller.appspot.com/bug?extid=f1cc2b579bf84a64d8c8
compiler: Debian clang version 20.1.6 (++20250514063057+1e4d39e07757-1~exp1~20250514183223.118), Debian LLD 20.1.6
userspace arch: arm64
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=152eca0c580000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=1339720c580000

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/13b062afcec7/disk-58485ff1.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/fdd4e489be2a/vmlinux-58485ff1.xz
kernel image: https://storage.googleapis.com/syzbot-assets/08bebb6045ec/Image-58485ff1.gz.xz
mounted in repro: https://storage.googleapis.com/syzbot-assets/170d98b6bbca/mount_0.gz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+f1cc2b...@syzkaller.appspotmail.com

Unable to handle kernel paging request at virtual address dfff800000000005
KASAN: null-ptr-deref in range [0x0000000000000028-0x000000000000002f]
Mem abort info:
ESR = 0x0000000096000006
EC = 0x25: DABT (current EL), IL = 32 bits
SET = 0, FnV = 0
EA = 0, S1PTW = 0
FSC = 0x06: level 2 translation fault
Data abort info:
ISV = 0, ISS = 0x00000006
CM = 0, WnR = 0
[dfff800000000005] address between user and kernel address ranges
Internal error: Oops: 0000000096000006 [#1] PREEMPT SMP
Modules linked in:
CPU: 0 PID: 4297 Comm: syz-executor921 Not tainted 6.1.141-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
pstate: 80400005 (Nzcv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--)
pc : udf_fiiter_write_fi+0x178/0xaa8 fs/udf/directory.c:405
lr : udf_fiiter_write_fi+0xd8/0xaa8 fs/udf/directory.c:401
sp : ffff8000207d74d0
x29: ffff8000207d7540 x28: ffff0000e01b1d60 x27: ffff8000207d76f0
x26: dfff800000000000 x25: 1ffff000040faf12 x24: 0000000000000200
x23: 0000000000000000 x22: ffff0000d76e87c0 x21: 0000000000000001
x20: 0000000000000028 x19: ffff8000207d7890 x18: 0000000000000000
x17: 000000000000001c x16: ffff8000082d1c00 x15: 0000000000000000
x14: 000000003b9aca00 x13: 000000001c03a180 x12: 0000000000ff0100
x11: ff008000098292dc x10: 0000000000000000 x9 : ffff0000d52c9bc0
x8 : 0000000000000005 x7 : 000000001c03a180 x6 : 0000000000000028
x5 : ffff0000d76e81e0 x4 : ffff0000d76e81d0 x3 : ffff800009814e68
x2 : 0000000000000010 x1 : 0000000000000000 x0 : 0000000000000003
Call trace:
udf_fiiter_write_fi+0x178/0xaa8 fs/udf/directory.c:405
udf_rename+0x960/0xa10 fs/udf/namei.c:860
vfs_rename+0x954/0xdcc fs/namei.c:4874
do_renameat2+0x738/0xa54 fs/namei.c:5027
__do_sys_renameat2 fs/namei.c:5060 [inline]
__se_sys_renameat2 fs/namei.c:5057 [inline]
__arm64_sys_renameat2+0xe0/0xfc fs/namei.c:5057
__invoke_syscall arch/arm64/kernel/syscall.c:38 [inline]
invoke_syscall+0x98/0x2bc arch/arm64/kernel/syscall.c:52
el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:140
do_el0_svc+0x58/0x13c arch/arm64/kernel/syscall.c:204
el0_svc+0x58/0x138 arch/arm64/kernel/entry-common.c:637
el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:655
el0t_64_sync+0x18c/0x190 arch/arm64/kernel/entry.S:585
Code: 97c2b1f6 f9400288 9100a114 d343fe88 (387a6908)
---[ end trace 0000000000000000 ]---
----------------
Code disassembly (best guess):
0: 97c2b1f6 bl 0xffffffffff0ac7d8
4: f9400288 ldr x8, [x20]
8: 9100a114 add x20, x8, #0x28
c: d343fe88 lsr x8, x20, #3
* 10: 387a6908 ldrb w8, [x8, x26] <-- trapping instruction


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