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BUG: KASAN: null-ptr-deref in instrument_atomic_read_write include/linux/instrumented.h:102 [inline]
BUG: KASAN: null-ptr-deref in atomic_fetch_add_relaxed include/linux/atomic/atomic-instrumented.h:116 [inline]
BUG: KASAN: null-ptr-deref in __refcount_add include/linux/refcount.h:193 [inline]
BUG: KASAN: null-ptr-deref in __refcount_inc include/linux/refcount.h:250 [inline]
BUG: KASAN: null-ptr-deref in refcount_inc include/linux/refcount.h:267 [inline]
BUG: KASAN: null-ptr-deref in get_task_struct include/linux/sched/task.h:110 [inline]
BUG: KASAN: null-ptr-deref in kthread_stop+0x2a/0x210 kernel/kthread.c:703
Write of size 4 at addr 0000000000000024 by task syz-executor.0/3762

CPU: 0 PID: 3762 Comm: syz-executor.0 Not tainted 6.1.0-rc2-syzkaller-00062-ga970174d7a10 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/11/2022
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x1e3/0x2cb lib/dump_stack.c:106
 print_report+0xed/0x220 mm/kasan/report.c:398
 kasan_report+0x139/0x170 mm/kasan/report.c:495
 kasan_check_range+0x2a7/0x2e0 mm/kasan/generic.c:189
 instrument_atomic_read_write include/linux/instrumented.h:102 [inline]
 atomic_fetch_add_relaxed include/linux/atomic/atomic-instrumented.h:116 [inline]
 __refcount_add include/linux/refcount.h:193 [inline]
 __refcount_inc include/linux/refcount.h:250 [inline]
 refcount_inc include/linux/refcount.h:267 [inline]
 get_task_struct include/linux/sched/task.h:110 [inline]
 kthread_stop+0x2a/0x210 kernel/kthread.c:703
 kill_f2fs_super+0xe6/0x3c0 fs/f2fs/super.c:4590
 deactivate_locked_super+0xa7/0xf0 fs/super.c:331
 cleanup_mnt+0x494/0x520 fs/namespace.c:1186
 task_work_run+0x243/0x300 kernel/task_work.c:179
 resume_user_mode_work include/linux/resume_user_mode.h:49 [inline]
 exit_to_user_mode_loop+0x134/0x160 kernel/entry/common.c:171
 exit_to_user_mode_prepare+0xad/0x110 kernel/entry/common.c:203
 __syscall_exit_to_user_mode_work kernel/entry/common.c:285 [inline]
 syscall_exit_to_user_mode+0x2e/0x60 kernel/entry/common.c:296
 entry_SYSCALL_64_after_hwframe+0x63/0xcd
RIP: 0033:0x7fd99e48ca67
Code: ff ff ff f7 d8 64 89 01 48 83 c8 ff c3 66 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 01 f0 ff ff 73 01 c3 48 c7 c1 b8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fff55e82368 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 00007fd99e48ca67
RDX: 00007fff55e8243b RSI: 000000000000000a RDI: 00007fff55e82430
RBP: 00007fff55e82430 R08: 00000000ffffffff R09: 00007fff55e82200
R10: 000055555582b8b3 R11: 0000000000000246 R12: 00007fd99e4e5826
R13: 00007fff55e834f0 R14: 000055555582b810 R15: 00007fff55e83530
 </TASK>
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