loop0: detected capacity change from 0 to 264192
F2FS-fs (loop0): invalid crc_offset: 0
F2FS-fs (loop0): Found nat_bits in checkpoint
F2FS-fs (loop0): Mounted with checkpoint version = 3651456e
==================================================================
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+0xc3/0x830 kernel/kthread.c:703
Write of size 4 at addr 000000000000001c by task syz-executor224/3611

CPU: 1 PID: 3611 Comm: syz-executor224 Not tainted 6.1.0-rc2-syzkaller #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+0xcd/0x134 lib/dump_stack.c:106
 kasan_report+0xbb/0x1f0 mm/kasan/report.c:495
 check_region_inline mm/kasan/generic.c:183 [inline]
 kasan_check_range+0x13d/0x180 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+0xc3/0x830 kernel/kthread.c:703
 f2fs_stop_discard_thread+0x91/0xb0 fs/f2fs/segment.c:1637
 kill_f2fs_super+0xda/0x3c0 fs/f2fs/super.c:4590
 deactivate_locked_super+0x94/0x160 fs/super.c:331
 deactivate_super+0xad/0xd0 fs/super.c:362
 cleanup_mnt+0x2ae/0x3d0 fs/namespace.c:1186
 task_work_run+0x16b/0x270 kernel/task_work.c:179
 exit_task_work include/linux/task_work.h:38 [inline]
 do_exit+0xb35/0x2a20 kernel/exit.c:820
 do_group_exit+0xd0/0x2a0 kernel/exit.c:950
 __do_sys_exit_group kernel/exit.c:961 [inline]
 __se_sys_exit_group kernel/exit.c:959 [inline]
 __x64_sys_exit_group+0x3a/0x50 kernel/exit.c:959
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd
RIP: 0033:0x7f5bf66d78c9
Code: Unable to access opcode bytes at 0x7f5bf66d789f.
RSP: 002b:00007ffd79bb07b8 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7
RAX: ffffffffffffffda RBX: 00007f5bf67483f0 RCX: 00007f5bf66d78c9
RDX: 000000000000003c RSI: 00000000000000e7 RDI: 0000000000000001
RBP: 0000000000000001 R08: ffffffffffffffc0 R09: 00007ffd79003031
R10: 0000000000180020 R11: 0000000000000246 R12: 00007f5bf67483f0
R13: 0000000000000001 R14: 0000000000000000 R15: 0000000000000001
 </TASK>
==================================================================