[v6.1] BUG: unable to handle kernel paging request in security_inode_getattr (2)

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 1989cd3d56e2 Linux 6.1.167
git tree: linux-6.1.y
console output: https://syzkaller.appspot.com/x/log.txt?x=10f34b52580000
kernel config: https://syzkaller.appspot.com/x/.config?x=b1adc0bfde2d8a4a
dashboard link: https://syzkaller.appspot.com/bug?extid=56a399c10b95faec2d59
compiler: Debian clang version 21.1.8 (++20251221033036+2078da43e25a-1~exp1~20251221153213.50), Debian LLD 21.1.8
userspace arch: arm64

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

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/edd05d4d1a68/disk-1989cd3d.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/bdc3181e838d/vmlinux-1989cd3d.xz
kernel image: https://storage.googleapis.com/syzbot-assets/a78aef5a3a25/Image-1989cd3d.gz.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+56a399...@syzkaller.appspotmail.com

Unable to handle kernel paging request at virtual address dfff80000000000d
KASAN: null-ptr-deref in range [0x0000000000000068-0x000000000000006f]
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
[dfff80000000000d] address between user and kernel address ranges
Internal error: Oops: 0000000096000006 [#1] PREEMPT SMP
Modules linked in:
CPU: 1 PID: 24445 Comm: syz.7.3466 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/26/2026
pstate: 82400005 (Nzcv daif +PAN -UAO +TCO -DIT -SSBS BTYPE=--)
pc : d_backing_inode include/linux/dcache.h:543 [inline]
pc : security_inode_getattr+0x48/0x124 security/security.c:1360
lr : security_inode_getattr+0x24/0x124 security/security.c:1359
sp : ffff8000218970b0
x29: ffff8000218970b0 x28: ffff8000218971c0 x27: f8f8f8f8f8f8f8f8
x26: 0000000000020401 x25: ffff0000e00c5a70 x24: ffff8000218973e0
x23: ffff0000e1905a70 x22: dfff800000000000 x21: ffff800021897400
x20: 0000000000000068 x19: ffff8000218973f0 x18: ffff800011b9bf60
x17: 1fffe00033eaa57e x16: ffff8000082eef80 x15: 0000000000000000
x14: 0000000000000002 x13: 1ffff00004312e7e x12: 0000000000080000
x11: 0000000000008087 x10: ffff800024209000 x9 : ffff80000a4ddb94
x8 : 000000000000000d x7 : 0000000000000000 x6 : 000000000000003f
x5 : 0000000000000040 x4 : 0000000000000000 x3 : 0000000000000000
x2 : 00000000000007ff x1 : ffff800021897400 x0 : ffff8000218973f0
Call trace:
d_backing_inode include/linux/dcache.h:543 [inline]
security_inode_getattr+0x48/0x124 security/security.c:1360
vfs_getattr+0x34/0x88 fs/stat.c:158
ovl_copy_up_one fs/overlayfs/copy_up.c:973 [inline]
ovl_copy_up_flags+0x2bc/0x2014 fs/overlayfs/copy_up.c:1059
ovl_maybe_copy_up+0x150/0x180 fs/overlayfs/copy_up.c:1091
ovl_open+0xe8/0x27c fs/overlayfs/file.c:152
do_dentry_open+0x72c/0xf98 fs/open.c:882
vfs_open+0x7c/0x90 fs/open.c:1015
do_open fs/namei.c:3634 [inline]
path_openat+0x1f8c/0x26bc fs/namei.c:3791
do_filp_open+0x194/0x384 fs/namei.c:3818
file_open_name+0x144/0x19c fs/open.c:1265
acct_on kernel/acct.c:235 [inline]
__do_sys_acct kernel/acct.c:328 [inline]
__se_sys_acct kernel/acct.c:315 [inline]
__arm64_sys_acct+0x128/0x714 kernel/acct.c:315
__invoke_syscall arch/arm64/kernel/syscall.c:38 [inline]
invoke_syscall+0x98/0x2b4 arch/arm64/kernel/syscall.c:52
el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:140
do_el0_svc+0x58/0x130 arch/arm64/kernel/syscall.c:204
el0_svc+0x58/0x128 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: 97902654 f9400288 9101a114 d343fe88 (38766908)
---[ end trace 0000000000000000 ]---
----------------
Code disassembly (best guess):
0: 97902654 bl 0xfffffffffe409950
4: f9400288 ldr x8, [x20]
8: 9101a114 add x20, x8, #0x68
c: d343fe88 lsr x8, x20, #3
* 10: 38766908 ldrb w8, [x8, x22] <-- trapping instruction


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