------------[ cut here ]------------
WARNING: CPU: 1 PID: 17830 at fs/inode.c:340 drop_nlink+0xce/0x110 fs/inode.c:340
Modules linked in:
CPU: 1 UID: 0 PID: 17830 Comm: syz-executor Not tainted syzkaller #0 3aa8e93a75ec4fb080c21ea51d8727149e6cfac5
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
RIP: 0010:drop_nlink+0xce/0x110 fs/inode.c:340
Code: 04 00 00 be 08 00 00 00 e8 5f 46 ee ff f0 48 ff 83 b8 04 00 00 5b 41 5c 41 5d 41 5e 41 5f 5d e9 d8 c5 a0 03 cc e8 82 0e 98 ff <0f> 0b eb 81 44 89 f1 80 e1 07 80 c1 03 38 c1 0f 8c 59 ff ff ff 4c
RSP: 0018:ffffc90004dc7a80 EFLAGS: 00010293
RAX: ffffffff81edd58e RBX: ffff88812e0b3838 RCX: ffff88814bc34c00
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffffc90004dc7aa8 R08: 0000000000000003 R09: 0000000000000004
R10: dffffc0000000000 R11: fffff520009b8f40 R12: dffffc0000000000
R13: 1ffff11025c16710 R14: ffff88812e0b3880 R15: 0000000000000000
FS: 0000000000000000(0000) GS:ffff8881f6f00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000110c281644 CR3: 000000011d03e000 CR4: 00000000003526b0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000001
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
Call Trace:
shmem_rmdir+0x5f/0x90 mm/shmem.c:3733
vfs_rmdir+0x3dd/0x560 fs/namei.c:4340
incfs_kill_sb+0x109/0x230 fs/incfs/vfs.c:1968
deactivate_locked_super+0xd8/0x2a0 fs/super.c:476
deactivate_super+0xb8/0xe0 fs/super.c:509
cleanup_mnt+0x3f1/0x480 fs/namespace.c:1370
__cleanup_mnt+0x1d/0x40 fs/namespace.c:1377
task_work_run+0x1e3/0x250 kernel/task_work.c:240
exit_task_work include/linux/task_work.h:43 [inline]
do_exit+0x9bc/0x2630 kernel/exit.c:953
do_group_exit+0x22a/0x300 kernel/exit.c:1095
__do_sys_exit_group kernel/exit.c:1106 [inline]
__se_sys_exit_group kernel/exit.c:1104 [inline]
__x64_sys_exit_group+0x43/0x50 kernel/exit.c:1104
x64_sys_call+0x2ed2/0x2ee0 arch/x86/include/generated/asm/syscalls_64.h:232
do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0x58/0xf0 arch/x86/entry/common.c:83
entry_SYSCALL_64_after_hwframe+0x76/0x7e
RIP: 0033:0x7f5a62b8ebe9
Code: Unable to access opcode bytes at 0x7f5a62b8ebbf.
RSP: 002b:00007ffd591ce5c8 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7
RAX: ffffffffffffffda RBX: 00007f5a62c11c77 RCX: 00007f5a62b8ebe9
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000001
RBP: 0000000000000016 R08: 00007ffd591cc366 R09: 00007ffd591cf880
R10: 000000000000000a R11: 0000000000000246 R12: 00007ffd591cf880
R13: 00007f5a62c11c05 R14: 0000555555e6b4a8 R15: 00007ffd591d1a40
---[ end trace 0000000000000000 ]---
==================================================================
BUG: KASAN: null-ptr-deref in instrument_atomic_read_write include/linux/instrumented.h:96 [inline]
BUG: KASAN: null-ptr-deref in atomic_inc_return include/linux/atomic/atomic-instrumented.h:453 [inline]
BUG: KASAN: null-ptr-deref in ihold+0x24/0x70 fs/inode.c:452
Write of size 4 at addr 0000000000000168 by task syz-executor/17830
CPU: 0 UID: 0 PID: 17830 Comm: syz-executor Tainted: G W syzkaller #0 3aa8e93a75ec4fb080c21ea51d8727149e6cfac5
Tainted: [W]=WARN
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
Call Trace:
__dump_stack+0x21/0x30 lib/dump_stack.c:94
dump_stack_lvl+0x10c/0x190 lib/dump_stack.c:120
print_report+0x3d/0x70 mm/kasan/report.c:482
kasan_report+0x163/0x1a0 mm/kasan/report.c:592
check_region_inline mm/kasan/generic.c:-1 [inline]
kasan_check_range+0x299/0x2a0 mm/kasan/generic.c:189
__kasan_check_write+0x18/0x20 mm/kasan/shadow.c:37
instrument_atomic_read_write include/linux/instrumented.h:96 [inline]
atomic_inc_return include/linux/atomic/atomic-instrumented.h:453 [inline]
ihold+0x24/0x70 fs/inode.c:452
d_delete_notify include/linux/fsnotify.h:357 [inline]
vfs_rmdir+0x26a/0x560 fs/namei.c:4353
incfs_kill_sb+0x109/0x230 fs/incfs/vfs.c:1968
deactivate_locked_super+0xd8/0x2a0 fs/super.c:476
deactivate_super+0xb8/0xe0 fs/super.c:509
cleanup_mnt+0x3f1/0x480 fs/namespace.c:1370
__cleanup_mnt+0x1d/0x40 fs/namespace.c:1377
task_work_run+0x1e3/0x250 kernel/task_work.c:240
exit_task_work include/linux/task_work.h:43 [inline]
do_exit+0x9bc/0x2630 kernel/exit.c:953
do_group_exit+0x22a/0x300 kernel/exit.c:1095
__do_sys_exit_group kernel/exit.c:1106 [inline]
__se_sys_exit_group kernel/exit.c:1104 [inline]
__x64_sys_exit_group+0x43/0x50 kernel/exit.c:1104
x64_sys_call+0x2ed2/0x2ee0 arch/x86/include/generated/asm/syscalls_64.h:232
do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0x58/0xf0 arch/x86/entry/common.c:83
entry_SYSCALL_64_after_hwframe+0x76/0x7e
RIP: 0033:0x7f5a62b8ebe9
Code: Unable to access opcode bytes at 0x7f5a62b8ebbf.
RSP: 002b:00007ffd591ce5c8 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7
RAX: ffffffffffffffda RBX: 00007f5a62c11c77 RCX: 00007f5a62b8ebe9
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000001
RBP: 0000000000000016 R08: 00007ffd591cc366 R09: 00007ffd591cf880
R10: 000000000000000a R11: 0000000000000246 R12: 00007ffd591cf880
R13: 00007f5a62c11c05 R14: 0000555555e6b4a8 R15: 00007ffd591d1a40
==================================================================
BUG: kernel NULL pointer dereference, address: 0000000000000168
#PF: supervisor write access in kernel mode
#PF: error_code(0x0002) - not-present page
PGD 0 P4D 0
Oops: Oops: 0002 [#1] PREEMPT SMP KASAN PTI
CPU: 0 UID: 0 PID: 17830 Comm: syz-executor Tainted: G B W syzkaller #0 3aa8e93a75ec4fb080c21ea51d8727149e6cfac5
Tainted: [B]=BAD_PAGE, [W]=WARN
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:85 [inline]
RIP: 0010:raw_atomic_add_return include/linux/atomic/atomic-arch-fallback.h:564 [inline]
RIP: 0010:raw_atomic_inc_return include/linux/atomic/atomic-arch-fallback.h:1020 [inline]
RIP: 0010:atomic_inc_return include/linux/atomic/atomic-instrumented.h:454 [inline]
RIP: 0010:ihold+0x2a/0x70 fs/inode.c:452
Code: f3 0f 1e fa 55 48 89 e5 41 56 53 48 89 fb e8 6d 05 98 ff 48 8d bb 68 01 00 00 be 04 00 00 00 e8 1c 3d ee ff 41 be 01 00 00 00 44 0f c1 b3 68 01 00 00 41 ff c6 bf 02 00 00 00 44 89 f6 e8 7d
RSP: 0018:ffffc90004dc7ac0 EFLAGS: 00010246
RAX: ffff88814bc34c00 RBX: 0000000000000000 RCX: ffff88814bc34c00
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffffc90004dc7ad0 R08: ffffffff8896d947 R09: 1ffffffff112db28
R10: dffffc0000000000 R11: fffffbfff112db29 R12: ffff88812e0b3844
R13: 0000000000000000 R14: 0000000000000001 R15: 0000000000000000
FS: 0000000000000000(0000) GS:ffff8881f6e00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000168 CR3: 000000010c6ae000 CR4: 00000000003526b0
Call Trace:
d_delete_notify include/linux/fsnotify.h:357 [inline]
vfs_rmdir+0x26a/0x560 fs/namei.c:4353
incfs_kill_sb+0x109/0x230 fs/incfs/vfs.c:1968
deactivate_locked_super+0xd8/0x2a0 fs/super.c:476
deactivate_super+0xb8/0xe0 fs/super.c:509
cleanup_mnt+0x3f1/0x480 fs/namespace.c:1370
__cleanup_mnt+0x1d/0x40 fs/namespace.c:1377
task_work_run+0x1e3/0x250 kernel/task_work.c:240
exit_task_work include/linux/task_work.h:43 [inline]
do_exit+0x9bc/0x2630 kernel/exit.c:953
do_group_exit+0x22a/0x300 kernel/exit.c:1095
__do_sys_exit_group kernel/exit.c:1106 [inline]
__se_sys_exit_group kernel/exit.c:1104 [inline]
__x64_sys_exit_group+0x43/0x50 kernel/exit.c:1104
x64_sys_call+0x2ed2/0x2ee0 arch/x86/include/generated/asm/syscalls_64.h:232
do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0x58/0xf0 arch/x86/entry/common.c:83
entry_SYSCALL_64_after_hwframe+0x76/0x7e
RIP: 0033:0x7f5a62b8ebe9
Code: Unable to access opcode bytes at 0x7f5a62b8ebbf.
RSP: 002b:00007ffd591ce5c8 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7
RAX: ffffffffffffffda RBX: 00007f5a62c11c77 RCX: 00007f5a62b8ebe9
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000001
RBP: 0000000000000016 R08: 00007ffd591cc366 R09: 00007ffd591cf880
R10: 000000000000000a R11: 0000000000000246 R12: 00007ffd591cf880
R13: 00007f5a62c11c05 R14: 0000555555e6b4a8 R15: 00007ffd591d1a40
Modules linked in:
CR2: 0000000000000168
---[ end trace 0000000000000000 ]---
RIP: 0010:arch_atomic_add_return arch/x86/include/asm/atomic.h:85 [inline]
RIP: 0010:raw_atomic_add_return include/linux/atomic/atomic-arch-fallback.h:564 [inline]
RIP: 0010:raw_atomic_inc_return include/linux/atomic/atomic-arch-fallback.h:1020 [inline]
RIP: 0010:atomic_inc_return include/linux/atomic/atomic-instrumented.h:454 [inline]
RIP: 0010:ihold+0x2a/0x70 fs/inode.c:452
Code: f3 0f 1e fa 55 48 89 e5 41 56 53 48 89 fb e8 6d 05 98 ff 48 8d bb 68 01 00 00 be 04 00 00 00 e8 1c 3d ee ff 41 be 01 00 00 00 44 0f c1 b3 68 01 00 00 41 ff c6 bf 02 00 00 00 44 89 f6 e8 7d
RSP: 0018:ffffc90004dc7ac0 EFLAGS: 00010246
RAX: ffff88814bc34c00 RBX: 0000000000000000 RCX: ffff88814bc34c00
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffffc90004dc7ad0 R08: ffffffff8896d947 R09: 1ffffffff112db28
R10: dffffc0000000000 R11: fffffbfff112db29 R12: ffff88812e0b3844
R13: 0000000000000000 R14: 0000000000000001 R15: 0000000000000000
FS: 0000000000000000(0000) GS:ffff8881f6e00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000168 CR3: 000000010c6ae000 CR4: 00000000003526b0
----------------
Code disassembly (best guess):
0: f3 0f 1e fa endbr64
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 6d 05 98 ff call 0xff980580
13: 48 8d bb 68 01 00 00 lea 0x168(%rbx),%rdi
1a: be 04 00 00 00 mov $0x4,%esi
1f: e8 1c 3d ee ff call 0xffee3d40
24: 41 be 01 00 00 00 mov $0x1,%r14d
* 2a: f0 44 0f c1 b3 68 01 lock xadd %r14d,0x168(%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: 7d .byte 0x7d