RAX: 0000000000000000 RBX: 0000000000000000 RCX: 00007f758e4df1f7
RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007ffe3c4ffec0
RBP: 00007ffe3c4ffec0 R08: 0000000000000000 R09: 0000000000000000
R10: 00000000ffffffff R11: 0000000000000246 R12: 00007ffe3c500f50
R13: 00007f758e560d7d R14: 0000000000008f88 R15: 00007ffe3c500f90
---[ end trace 4c0e6e3809cfe76c ]---
==================================================================
BUG: KASAN: null-ptr-deref in instrument_atomic_read_write include/linux/instrumented.h:101 [inline]
BUG: KASAN: null-ptr-deref in atomic_inc_return include/asm-generic/atomic-instrumented.h:250 [inline]
BUG: KASAN: null-ptr-deref in ihold+0x20/0x60 fs/inode.c:423
Write of size 4 at addr 0000000000000170 by task syz-executor/275
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025
Call Trace:
__dump_stack+0x21/0x24 lib/dump_stack.c:77
dump_stack_lvl+0x169/0x1d8 lib/dump_stack.c:118
__kasan_report mm/kasan/report.c:439 [inline]
kasan_report+0xd8/0x130 mm/kasan/report.c:452
check_region_inline mm/kasan/generic.c:-1 [inline]
kasan_check_range+0x280/0x290 mm/kasan/generic.c:189
__kasan_check_write+0x14/0x20 mm/kasan/shadow.c:37
incfs_kill_sb+0xfe/0x210 fs/incfs/vfs.c:1973
deactivate_locked_super+0xa0/0x100 fs/super.c:335
deactivate_super+0xaf/0xe0 fs/super.c:366
cleanup_mnt+0x446/0x500 fs/namespace.c:1114
__cleanup_mnt+0x19/0x20 fs/namespace.c:1121
task_work_run+0x127/0x190 kernel/task_work.c:189
tracehook_notify_resume include/linux/tracehook.h:188 [inline]
exit_to_user_mode_loop+0xcb/0xe0 kernel/entry/common.c:172
exit_to_user_mode_prepare+0x76/0xa0 kernel/entry/common.c:199
syscall_exit_to_user_mode+0x1d/0x40 kernel/entry/common.c:274
do_syscall_64+0x3d/0x40 arch/x86/entry/common.c:56
entry_SYSCALL_64_after_hwframe+0x61/0xcb
RIP: 0033:0x7f758e4df1f7
Code: a8 ff ff ff f7 d8 64 89 01 48 83 c8 ff c3 0f 1f 44 00 00 31 f6 e9 09 00 00 00 66 0f 1f 84 00 00 00 00 00 b8 a6 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 01 c3 48 c7 c2 a8 ff ff ff f7 d8 64 89 02 b8
RSP: 002b:00007ffe3c4ffe08 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 00007f758e4df1f7
RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007ffe3c4ffec0
RBP: 00007ffe3c4ffec0 R08: 0000000000000000 R09: 0000000000000000
R10: 00000000ffffffff R11: 0000000000000246 R12: 00007ffe3c500f50
R13: 00007f758e560d7d R14: 0000000000008f88 R15: 00007ffe3c500f90
==================================================================
BUG: kernel NULL pointer dereference, address: 0000000000000170
#PF: supervisor write access in kernel mode
#PF: error_code(0x0002) - not-present page
PGD 10fa0b067 P4D 10fa0b067 PUD 0
Oops: 0002 [#1] PREEMPT SMP KASAN
CPU: 1 PID: 275 Comm: syz-executor Tainted: G B W syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025
RIP: 0010:arch_atomic_add_return arch/x86/include/asm/atomic.h:165 [inline]
RIP: 0010:arch_atomic_inc_return include/linux/atomic-arch-fallback.h:286 [inline]
RIP: 0010:atomic_inc_return include/asm-generic/atomic-instrumented.h:251 [inline]
RIP: 0010:ihold+0x26/0x60 fs/inode.c:423
Code: 00 00 00 00 55 48 89 e5 41 56 53 48 89 fb e8 d1 28 b8 ff 48 8d bb 70 01 00 00 be 04 00 00 00 e8 80 1a f2 ff 41 be 01 00 00 00 <f0> 44 0f c1 b3 70 01 00 00 41 ff c6 bf 02 00 00 00 44 89 f6 e8 51
RSP: 0018:ffffc90000c07d10 EFLAGS: 00010246
RAX: ffff88811e658000 RBX: 0000000000000000 RCX: 0000000000000286
RDX: 0000000000000000 RSI: 0000000000000002 RDI: 00000000ffffffff
RBP: ffffc90000c07d20 R08: 0000000000000004 R09: 0000000000000003
R10: fffffbfff0d8ee48 R11: 1ffffffff0d8ee48 R12: 1ffff110235fd66c
R13: 0000000000000000 R14: 0000000000000001 R15: 0000000000000000
FS: 00005555847d9500(0000) GS:ffff8881f7100000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000170 CR3: 0000000124b22000 CR4: 00000000003506a0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
d_delete_notify include/linux/fsnotify.h:264 [inline]
vfs_rmdir+0x247/0x3e0 fs/namei.c:3865
incfs_kill_sb+0xfe/0x210 fs/incfs/vfs.c:1973
deactivate_locked_super+0xa0/0x100 fs/super.c:335
deactivate_super+0xaf/0xe0 fs/super.c:366
cleanup_mnt+0x446/0x500 fs/namespace.c:1114
__cleanup_mnt+0x19/0x20 fs/namespace.c:1121
task_work_run+0x127/0x190 kernel/task_work.c:189
tracehook_notify_resume include/linux/tracehook.h:188 [inline]
exit_to_user_mode_loop+0xcb/0xe0 kernel/entry/common.c:172
exit_to_user_mode_prepare+0x76/0xa0 kernel/entry/common.c:199
syscall_exit_to_user_mode+0x1d/0x40 kernel/entry/common.c:274
do_syscall_64+0x3d/0x40 arch/x86/entry/common.c:56
entry_SYSCALL_64_after_hwframe+0x61/0xcb
RIP: 0033:0x7f758e4df1f7
Code: a8 ff ff ff f7 d8 64 89 01 48 83 c8 ff c3 0f 1f 44 00 00 31 f6 e9 09 00 00 00 66 0f 1f 84 00 00 00 00 00 b8 a6 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 01 c3 48 c7 c2 a8 ff ff ff f7 d8 64 89 02 b8
RSP: 002b:00007ffe3c4ffe08 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 00007f758e4df1f7
RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007ffe3c4ffec0
RBP: 00007ffe3c4ffec0 R08: 0000000000000000 R09: 0000000000000000
R10: 00000000ffffffff R11: 0000000000000246 R12: 00007ffe3c500f50
R13: 00007f758e560d7d R14: 0000000000008f88 R15: 00007ffe3c500f90
Modules linked in:
CR2: 0000000000000170
---[ end trace 4c0e6e3809cfe76d ]---
RIP: 0010:arch_atomic_add_return arch/x86/include/asm/atomic.h:165 [inline]
RIP: 0010:arch_atomic_inc_return include/linux/atomic-arch-fallback.h:286 [inline]
RIP: 0010:atomic_inc_return include/asm-generic/atomic-instrumented.h:251 [inline]
RIP: 0010:ihold+0x26/0x60 fs/inode.c:423
Code: 00 00 00 00 55 48 89 e5 41 56 53 48 89 fb e8 d1 28 b8 ff 48 8d bb 70 01 00 00 be 04 00 00 00 e8 80 1a f2 ff 41 be 01 00 00 00 <f0> 44 0f c1 b3 70 01 00 00 41 ff c6 bf 02 00 00 00 44 89 f6 e8 51
RSP: 0018:ffffc90000c07d10 EFLAGS: 00010246
RAX: ffff88811e658000 RBX: 0000000000000000 RCX: 0000000000000286
RDX: 0000000000000000 RSI: 0000000000000002 RDI: 00000000ffffffff
RBP: ffffc90000c07d20 R08: 0000000000000004 R09: 0000000000000003
R10: fffffbfff0d8ee48 R11: 1ffffffff0d8ee48 R12: 1ffff110235fd66c
R13: 0000000000000000 R14: 0000000000000001 R15: 0000000000000000
FS: 00005555847d9500(0000) GS:ffff8881f7100000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000170 CR3: 0000000124b22000 CR4: 00000000003506a0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
----------------
Code disassembly (best guess):
0: 00 00 add %al,(%rax)
2: 00 00 add %al,(%rax)
4: 55 push %rbp
5: 48 89 e5 mov %rsp,%rbp
8: 41 56 push %r14
a: 53 push %rbx
b: 48 89 fb mov %rdi,%rbx
e: e8 d1 28 b8 ff call 0xffb828e4
13: 48 8d bb 70 01 00 00 lea 0x170(%rbx),%rdi
1a: be 04 00 00 00 mov $0x4,%esi
1f: e8 80 1a f2 ff call 0xfff21aa4
24: 41 be 01 00 00 00 mov $0x1,%r14d
* 2a: f0 44 0f c1 b3 70 01 lock xadd %r14d,0x170(%rbx) <-- trapping instruction
31: 00 00
33: 41 ff c6 inc %r14d
36: bf 02 00 00 00 mov $0x2,%edi
3b: 44 89 f6 mov %r14d,%esi
3e: e8 .byte 0xe8
3f: 51 push %rcx