RAX: 0000000000000000 RBX: 0000000000000000 RCX: 00007fbd7978ff17
RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007ffdbe23dbc0
RBP: 00007ffdbe23dbc0 R08: 0000000000000000 R09: 0000000000000000
R10: 00000000ffffffff R11: 0000000000000246 R12: 00007ffdbe23ec50
R13: 00007fbd79811c05 R14: 0000000000005dd5 R15: 00007ffdbe23ec90
---[ end trace 0000000000000000 ]---
==================================================================
BUG: KASAN: null-ptr-deref in instrument_atomic_read_write include/linux/instrumented.h:102 [inline]
BUG: KASAN: null-ptr-deref in atomic_inc_return include/linux/atomic/atomic-instrumented.h:198 [inline]
BUG: KASAN: null-ptr-deref in ihold+0x20/0x60 fs/inode.c:452
Write of size 4 at addr 0000000000000170 by task syz-executor/365
CPU: 0 PID: 365 Comm: syz-executor Tainted: G W syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
Call Trace:
__dump_stack+0x21/0x24 lib/dump_stack.c:88
dump_stack_lvl+0xee/0x150 lib/dump_stack.c:106
print_report+0x3d/0x60 mm/kasan/report.c:430
kasan_report+0x122/0x150 mm/kasan/report.c:531
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
instrument_atomic_read_write include/linux/instrumented.h:102 [inline]
atomic_inc_return include/linux/atomic/atomic-instrumented.h:198 [inline]
ihold+0x20/0x60 fs/inode.c:452
d_delete_notify include/linux/fsnotify.h:289 [inline]
vfs_rmdir+0x25f/0x500 fs/namei.c:4203
incfs_kill_sb+0x105/0x220 fs/incfs/vfs.c:1995
deactivate_locked_super+0xb5/0x120 fs/super.c:334
deactivate_super+0xaf/0xe0 fs/super.c:365
cleanup_mnt+0x45f/0x4e0 fs/namespace.c:1182
__cleanup_mnt+0x19/0x20 fs/namespace.c:1189
task_work_run+0x1db/0x240 kernel/task_work.c:203
resume_user_mode_work include/linux/resume_user_mode.h:49 [inline]
exit_to_user_mode_loop+0x9b/0xb0 kernel/entry/common.c:177
exit_to_user_mode_prepare+0x5a/0xa0 kernel/entry/common.c:210
__syscall_exit_to_user_mode_work kernel/entry/common.c:292 [inline]
syscall_exit_to_user_mode+0x1a/0x30 kernel/entry/common.c:303
do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:87
entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7fbd7978ff17
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:00007ffdbe23db08 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 00007fbd7978ff17
RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007ffdbe23dbc0
RBP: 00007ffdbe23dbc0 R08: 0000000000000000 R09: 0000000000000000
R10: 00000000ffffffff R11: 0000000000000246 R12: 00007ffdbe23ec50
R13: 00007fbd79811c05 R14: 0000000000005dd5 R15: 00007ffdbe23ec90
==================================================================
BUG: kernel NULL pointer dereference, address: 0000000000000170
#PF: supervisor write access in kernel mode
#PF: error_code(0x0002) - not-present page
PGD 12d98b067 P4D 12d98b067 PUD 0
Oops: 0002 [#1] PREEMPT SMP KASAN
CPU: 1 PID: 365 Comm: syz-executor Tainted: G B W syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
RIP: 0010:arch_atomic_add_return arch/x86/include/asm/atomic.h:165 [inline]
RIP: 0010:arch_atomic_inc_return include/linux/atomic/atomic-arch-fallback.h:440 [inline]
RIP: 0010:atomic_inc_return include/linux/atomic/atomic-instrumented.h:199 [inline]
RIP: 0010:ihold+0x26/0x60 fs/inode.c:452
Code: 33 36 7c df 55 48 89 e5 41 56 53 48 89 fb e8 c1 81 ac ff 48 8d bb 70 01 00 00 be 04 00 00 00 e8 40 e1 f0 ff 41 be 01 00 00 00 44 0f c1 b3 70 01 00 00 41 ff c6 bf 02 00 00 00 44 89 f6 e8 b1
RSP: 0018:ffffc900009e7c78 EFLAGS: 00010246
RAX: ffff88811a7b0000 RBX: 0000000000000000 RCX: ffff88811a7b0000
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffffc900009e7c88 R08: dffffc0000000000 R09: fffffbfff0f2d4fd
R10: fffffbfff0f2d4fd R11: 1ffffffff0f2d4fc R12: ffff8881179b0be4
R13: dffffc0000000000 R14: 0000000000000001 R15: 0000000000000000
FS: 0000555557162500(0000) GS:ffff8881f7100000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000170 CR3: 000000012a7e9000 CR4: 00000000003506a0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
d_delete_notify include/linux/fsnotify.h:289 [inline]
vfs_rmdir+0x25f/0x500 fs/namei.c:4203
incfs_kill_sb+0x105/0x220 fs/incfs/vfs.c:1995
deactivate_locked_super+0xb5/0x120 fs/super.c:334
deactivate_super+0xaf/0xe0 fs/super.c:365
cleanup_mnt+0x45f/0x4e0 fs/namespace.c:1182
__cleanup_mnt+0x19/0x20 fs/namespace.c:1189
task_work_run+0x1db/0x240 kernel/task_work.c:203
resume_user_mode_work include/linux/resume_user_mode.h:49 [inline]
exit_to_user_mode_loop+0x9b/0xb0 kernel/entry/common.c:177
exit_to_user_mode_prepare+0x5a/0xa0 kernel/entry/common.c:210
__syscall_exit_to_user_mode_work kernel/entry/common.c:292 [inline]
syscall_exit_to_user_mode+0x1a/0x30 kernel/entry/common.c:303
do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:87
entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7fbd7978ff17
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:00007ffdbe23db08 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 00007fbd7978ff17
RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007ffdbe23dbc0
RBP: 00007ffdbe23dbc0 R08: 0000000000000000 R09: 0000000000000000
R10: 00000000ffffffff R11: 0000000000000246 R12: 00007ffdbe23ec50
R13: 00007fbd79811c05 R14: 0000000000005dd5 R15: 00007ffdbe23ec90
Modules linked in:
CR2: 0000000000000170
---[ end trace 0000000000000000 ]---
RIP: 0010:arch_atomic_add_return arch/x86/include/asm/atomic.h:165 [inline]
RIP: 0010:arch_atomic_inc_return include/linux/atomic/atomic-arch-fallback.h:440 [inline]
RIP: 0010:atomic_inc_return include/linux/atomic/atomic-instrumented.h:199 [inline]
RIP: 0010:ihold+0x26/0x60 fs/inode.c:452
Code: 33 36 7c df 55 48 89 e5 41 56 53 48 89 fb e8 c1 81 ac ff 48 8d bb 70 01 00 00 be 04 00 00 00 e8 40 e1 f0 ff 41 be 01 00 00 00 44 0f c1 b3 70 01 00 00 41 ff c6 bf 02 00 00 00 44 89 f6 e8 b1
RSP: 0018:ffffc900009e7c78 EFLAGS: 00010246
RAX: ffff88811a7b0000 RBX: 0000000000000000 RCX: ffff88811a7b0000
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffffc900009e7c88 R08: dffffc0000000000 R09: fffffbfff0f2d4fd
R10: fffffbfff0f2d4fd R11: 1ffffffff0f2d4fc R12: ffff8881179b0be4
R13: dffffc0000000000 R14: 0000000000000001 R15: 0000000000000000
FS: 0000555557162500(0000) GS:ffff8881f7100000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000170 CR3: 000000012a7e9000 CR4: 00000000003506a0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
----------------
Code disassembly (best guess):
0: 33 36 xor (%rsi),%esi
2: 7c df jl 0xffffffe3
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 c1 81 ac ff call 0xffac81d4
13: 48 8d bb 70 01 00 00 lea 0x170(%rbx),%rdi
1a: be 04 00 00 00 mov $0x4,%esi
1f: e8 40 e1 f0 ff call 0xfff0e164
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: b1 .byte 0xb1