[syzbot] BUG: unable to handle kernel NULL pointer dereference in f2fs_update_meta_page (2)

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: ae085d7f9365 mm: kfence: fix missing objcg housekeeping fo..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=12a11a77700000
kernel config: https://syzkaller.appspot.com/x/.config?x=91f0a0c422e301dd
dashboard link: https://syzkaller.appspot.com/bug?extid=9e29d4a176b24eaa4fc1
compiler: Debian clang version 11.0.1-2, GNU ld (GNU Binutils for Debian) 2.35.2

Unfortunately, I don't have any reproducer for this issue yet.

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+9e29d4...@syzkaller.appspotmail.com

BUG: kernel NULL pointer dereference, address: 0000000000000000
#PF: supervisor instruction fetch in kernel mode
#PF: error_code(0x0010) - not-present page
PGD 1ef8e067 P4D 1ef8e067 PUD 0
Oops: 0010 [#1] PREEMPT SMP KASAN
CPU: 0 PID: 3615 Comm: syz-executor.0 Tainted: G W 5.17.0-syzkaller-11407-gae085d7f9365 #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:ffffc9000400f818 EFLAGS: 00010286
RAX: 0000000000000000 RBX: ffffea0000c768c0 RCX: ffff88801a581d00
RDX: 0000000000000000 RSI: ffffea0000c768c0 RDI: ffff88802c0203b8
RBP: ffffc9000400faf0 R08: ffffffff81b497cb R09: fffff9400018ed19
R10: fffff9400018ed19 R11: 0000000000000000 R12: ffff88807bb85b10
R13: 0000000000000001 R14: ffff888040fea000 R15: ffff888058d74000
FS: 000055555607f400(0000) GS:ffff8880b9a00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: ffffffffffffffd6 CR3: 00000000479d6000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
<TASK>
f2fs_update_meta_page+0x45/0x60 fs/f2fs/segment.c:2484
do_checkpoint fs/f2fs/checkpoint.c:1527 [inline]
f2fs_write_checkpoint+0x3136/0x5b80 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:4546
deactivate_locked_super+0xa7/0xf0 fs/super.c:332
cleanup_mnt+0x462/0x510 fs/namespace.c:1186
task_work_run+0x146/0x1c0 kernel/task_work.c:164
tracehook_notify_resume include/linux/tracehook.h:188 [inline]
exit_to_user_mode_loop kernel/entry/common.c:190 [inline]
exit_to_user_mode_prepare+0x1dd/0x200 kernel/entry/common.c:222
__syscall_exit_to_user_mode_work kernel/entry/common.c:304 [inline]
syscall_exit_to_user_mode+0x2e/0x70 kernel/entry/common.c:315
entry_SYSCALL_64_after_hwframe+0x44/0xae
RIP: 0033:0x7f48a848a4b7
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:00007ffd9c82d6e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 00007f48a848a4b7
RDX: 00007ffd9c82d7bc RSI: 000000000000000a RDI: 00007ffd9c82d7b0
RBP: 00007ffd9c82d7b0 R08: 00000000ffffffff R09: 00007ffd9c82d580
R10: 00005555560808b3 R11: 0000000000000246 R12: 00007f48a84e21ea
R13: 00007ffd9c82e870 R14: 0000555556080810 R15: 00007ffd9c82e8b0
</TASK>
Modules linked in:
CR2: 0000000000000000
---[ end trace 0000000000000000 ]---
RIP: 0010:0x0
Code: Unable to access opcode bytes at RIP 0xffffffffffffffd6.
RSP: 0018:ffffc9000400f818 EFLAGS: 00010286
RAX: 0000000000000000 RBX: ffffea0000c768c0 RCX: ffff88801a581d00
RDX: 0000000000000000 RSI: ffffea0000c768c0 RDI: ffff88802c0203b8
RBP: ffffc9000400faf0 R08: ffffffff81b497cb R09: fffff9400018ed19
R10: fffff9400018ed19 R11: 0000000000000000 R12: ffff88807bb85b10
R13: 0000000000000001 R14: ffff888040fea000 R15: ffff888058d74000
FS: 000055555607f400(0000) GS:ffff8880b9a00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: ffffffffffffffd6 CR3: 00000000479d6000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400


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[syzbot]

Auto-closing this bug as obsolete.
Crashes did not happen for a while, no reproducer and no activity.