ntfs: (device loop4): ntfs_filldir(): Skipping unrepresentable inode 0x4.
ntfs: (device loop4): ntfs_lookup(): ntfs_lookup_ino_by_name() failed with error code -24.
==================================================================
BUG: KASAN: null-ptr-deref in traverse_mounts fs/namei.c:1378 [inline]
BUG: KASAN: null-ptr-deref in handle_mounts fs/namei.c:1498 [inline]
BUG: KASAN: null-ptr-deref in step_into+0xfc/0xa24 fs/namei.c:1806
Read of size 4 at addr 0000000000000018 by task syz-executor/4033

CPU: 0 PID: 4033 Comm: syz-executor Not tainted 5.15.181-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/19/2025
Call trace:
 dump_backtrace+0x0/0x43c arch/arm64/kernel/stacktrace.c:152
 show_stack+0x2c/0x3c arch/arm64/kernel/stacktrace.c:216
 __dump_stack+0x30/0x40 lib/dump_stack.c:88
 dump_stack_lvl+0xf8/0x160 lib/dump_stack.c:106
 __kasan_report mm/kasan/report.c:438 [inline]
 kasan_report+0xe0/0x15c mm/kasan/report.c:451
 check_region_inline mm/kasan/generic.c:-1 [inline]
 kasan_check_range+0x270/0x2b0 mm/kasan/generic.c:189
 __kasan_check_read+0x44/0x54 mm/kasan/shadow.c:31
 traverse_mounts fs/namei.c:1378 [inline]
 handle_mounts fs/namei.c:1498 [inline]
 step_into+0xfc/0xa24 fs/namei.c:1806
 walk_component+0x1f0/0x3a8 fs/namei.c:1982
 lookup_last fs/namei.c:2431 [inline]
 path_lookupat+0x13c/0x3d0 fs/namei.c:2455
 filename_lookup+0x180/0x414 fs/namei.c:2484
 user_path_at_empty+0x5c/0x1a0 fs/namei.c:2883
 user_path_at include/linux/namei.h:57 [inline]
 ksys_umount fs/namespace.c:1780 [inline]
 __do_sys_umount fs/namespace.c:1788 [inline]
 __se_sys_umount fs/namespace.c:1786 [inline]
 __arm64_sys_umount+0xf4/0x178 fs/namespace.c:1786
 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline]
 invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:52
 el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:142
 do_el0_svc+0x58/0x14c arch/arm64/kernel/syscall.c:181
 el0_svc+0x78/0x1e0 arch/arm64/kernel/entry-common.c:608
 el0t_64_sync_handler+0xcc/0xe4 arch/arm64/kernel/entry-common.c:626
 el0t_64_sync+0x1a0/0x1a4 arch/arm64/kernel/entry.S:584
==================================================================
Unable to handle kernel NULL pointer dereference at virtual address 0000000000000018
Mem abort info:
  ESR = 0x0000000096000005
  EC = 0x25: DABT (current EL), IL = 32 bits
  SET = 0, FnV = 0
  EA = 0, S1PTW = 0
  FSC = 0x05: level 1 translation fault
Data abort info:
  ISV = 0, ISS = 0x00000005
  CM = 0, WnR = 0
user pgtable: 4k pages, 48-bit VAs, pgdp=00000001249f0000
[0000000000000018] pgd=08000001084c7003, p4d=08000001084c7003, pud=0000000000000000
Internal error: Oops: 0000000096000005 [#1] PREEMPT SMP
Modules linked in:
CPU: 1 PID: 4033 Comm: syz-executor Tainted: G    B             5.15.181-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/19/2025
pstate: 80400005 (Nzcv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--)
pc : traverse_mounts fs/namei.c:1378 [inline]
pc : handle_mounts fs/namei.c:1498 [inline]
pc : step_into+0xfc/0xa24 fs/namei.c:1806
lr : traverse_mounts fs/namei.c:1378 [inline]
lr : handle_mounts fs/namei.c:1498 [inline]
lr : step_into+0xfc/0xa24 fs/namei.c:1806
sp : ffff80001b7e78c0
x29: ffff80001b7e7980 x28: 1ffff000036fcf67 x27: dfff800000000000
x26: 1ffff000036fcf6a x25: 0000000000000018 x24: 0000000000000080
x23: 0000000000000000 x22: ffff80001b7e7b38 x21: 0000000000000000
x20: 0000000000000080 x19: ffff80001b7e7b00 x18: 0000000000000002
x17: 0000000040000000 x16: ffff8000082d4b24 x15: 0000000000000002
x14: 0000000000ff0100 x13: ffffffffffffffff x12: 0000000000ff0100
x11: 0000000000000000 x10: 0000000000000000 x9 : 0000000000000000
x8 : 0000000000000000 x7 : 0000000000000000 x6 : ffff800008244078
x5 : 0000000000000000 x4 : 0000000000000000 x3 : ffff800008184528
x2 : 0000000000000001 x1 : 0000000000000001 x0 : 0000000000000000
Call trace:
 traverse_mounts fs/namei.c:1378 [inline]
 handle_mounts fs/namei.c:1498 [inline]
 step_into+0xfc/0xa24 fs/namei.c:1806
 walk_component+0x1f0/0x3a8 fs/namei.c:1982
 lookup_last fs/namei.c:2431 [inline]
 path_lookupat+0x13c/0x3d0 fs/namei.c:2455
 filename_lookup+0x180/0x414 fs/namei.c:2484
 user_path_at_empty+0x5c/0x1a0 fs/namei.c:2883
 user_path_at include/linux/namei.h:57 [inline]
 ksys_umount fs/namespace.c:1780 [inline]
 __do_sys_umount fs/namespace.c:1788 [inline]
 __se_sys_umount fs/namespace.c:1786 [inline]
 __arm64_sys_umount+0xf4/0x178 fs/namespace.c:1786
 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline]
 invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:52
 el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:142
 do_el0_svc+0x58/0x14c arch/arm64/kernel/syscall.c:181
 el0_svc+0x78/0x1e0 arch/arm64/kernel/entry-common.c:608
 el0t_64_sync_handler+0xcc/0xe4 arch/arm64/kernel/entry-common.c:626
 el0t_64_sync+0x1a0/0x1a4 arch/arm64/kernel/entry.S:584
Code: b94002d8 52800081 aa1903e0 97fca00f (88dfff39) 
---[ end trace 67597d60fbd34f6a ]---
----------------
Code disassembly (best guess):
   0:	b94002d8 	ldr	w24, [x22]
   4:	52800081 	mov	w1, #0x4                   	// #4
   8:	aa1903e0 	mov	x0, x25
   c:	97fca00f 	bl	0xfffffffffff28048
* 10:	88dfff39 	ldar	w25, [x25] <-- trapping instruction