BUG: kernel NULL pointer dereference, address: 0000000000000000
#PF: supervisor instruction fetch in kernel mode
#PF: error_code(0x0010) - not-present page
PGD 6b401067 P4D 6b401067 PUD 0 
Oops: 0010 [#1] PREEMPT SMP KASAN
CPU: 0 PID: 3625 Comm: syz-executor.5 Not tainted 5.18.0-rc7-syzkaller-00006-g210e04ff7681 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:0x0
Code: Unable to access opcode bytes at RIP 0xffffffffffffffd6.
RSP: 0018:ffffc900031cf738 EFLAGS: 00010282
RAX: 0000000000000000 RBX: ffffea0000e6cb40 RCX: ffff88801f138000
RDX: 0000000000000000 RSI: ffffea0000e6cb40 RDI: ffff888029a183b8
RBP: ffffc900031cf930 R08: ffffffff81b3b7bb R09: fffff940001cd969
R10: fffff940001cd969 R11: 1ffffd40001cd968 R12: ffff88807de08310
R13: 0000000000000001 R14: ffff888044d8c000 R15: ffff88801b334000
FS:  0000555555c85400(0000) GS:ffff8880b9a00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: ffffffffffffffd6 CR3: 0000000040069000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 000000000000003b DR6: 00000000ffff0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 f2fs_update_meta_page+0x45/0x60 fs/f2fs/segment.c:2484
 do_checkpoint+0x1ce2/0x4020 fs/f2fs/checkpoint.c:1527
 f2fs_write_checkpoint+0x15a1/0x1d70 fs/f2fs/checkpoint.c:1689
 f2fs_issue_checkpoint+0x361/0x4e0
 sync_filesystem+0x1bc/0x220 fs/sync.c:66
 generic_shutdown_super+0x6b/0x300 fs/super.c:445
 kill_block_super+0x79/0xd0 fs/super.c:1394
 kill_f2fs_super+0x2f9/0x3c0 fs/f2fs/super.c:4516
 deactivate_locked_super+0xa7/0xf0 fs/super.c:332
 cleanup_mnt+0x452/0x500 fs/namespace.c:1186
 task_work_run+0x146/0x1c0 kernel/task_work.c:164
 resume_user_mode_work include/linux/resume_user_mode.h:49 [inline]
 exit_to_user_mode_loop+0x134/0x160 kernel/entry/common.c:169
 exit_to_user_mode_prepare+0xad/0x110 kernel/entry/common.c:201
 __syscall_exit_to_user_mode_work kernel/entry/common.c:283 [inline]
 syscall_exit_to_user_mode+0x2e/0x70 kernel/entry/common.c:294
 entry_SYSCALL_64_after_hwframe+0x44/0xae
RIP: 0033:0x7f98ec28a557
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:00007ffdd2cd1588 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 00007f98ec28a557
RDX: 00007ffdd2cd165c RSI: 000000000000000a RDI: 00007ffdd2cd1650
RBP: 00007ffdd2cd1650 R08: 00000000ffffffff R09: 00007ffdd2cd1420
R10: 0000555555c868b3 R11: 0000000000000246 R12: 00007f98ec2e21f8
R13: 00007ffdd2cd2710 R14: 0000555555c86810 R15: 00007ffdd2cd2750
 </TASK>
Modules linked in:
CR2: 0000000000000000
---[ end trace 0000000000000000 ]---
RIP: 0010:0x0
Code: Unable to access opcode bytes at RIP 0xffffffffffffffd6.
RSP: 0018:ffffc900031cf738 EFLAGS: 00010282
RAX: 0000000000000000 RBX: ffffea0000e6cb40 RCX: ffff88801f138000
RDX: 0000000000000000 RSI: ffffea0000e6cb40 RDI: ffff888029a183b8
RBP: ffffc900031cf930 R08: ffffffff81b3b7bb R09: fffff940001cd969
R10: fffff940001cd969 R11: 1ffffd40001cd968 R12: ffff88807de08310
R13: 0000000000000001 R14: ffff888044d8c000 R15: ffff88801b334000
FS:  0000555555c85400(0000) GS:ffff8880b9a00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: ffffffffffffffd6 CR3: 0000000040069000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 000000000000003b DR6: 00000000ffff0ff0 DR7: 0000000000000400