[syzbot] WARNING in kernfs_find_and_get_node_by_id

[syzbot <syzbot+2fdf66e68f5f882c1074@syzkaller.appspotmail.com>]

Hello,

syzbot found the following issue on:

HEAD commit:    f2f32f8af2b0 Merge tag 'for-6.1-rc3-tag' of git://git.kern..
git tree:       upstream
console+strace: https://syzkaller.appspot.com/x/log.txt?x=101fe196880000
kernel config:  https://syzkaller.appspot.com/x/.config?x=f7e100ed8aaa828e
dashboard link: https://syzkaller.appspot.com/bug?extid=2fdf66e68f5f882c1074
compiler:       Debian clang version 13.0.1-++20220126092033+75e33f71c2da-1~exp1~20220126212112.63, GNU ld (GNU Binutils for Debian) 2.35.2
syz repro:      https://syzkaller.appspot.com/x/repro.syz?x=14aa1051880000
C reproducer:   https://syzkaller.appspot.com/x/repro.c?x=10a863a6880000

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/ea126f52b953/disk-f2f32f8a.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/815b36048854/vmlinux-f2f32f8a.xz
kernel image: https://storage.googleapis.com/syzbot-assets/b7d04bb936fd/bzImage-f2f32f8a.xz

The issue was bisected to:

commit c25491747b21536bd56dccb82a109754bbc8d52c
Author: Tejun Heo <tj@kernel.org>
Date:   Sun Aug 28 05:04:37 2022 +0000

    kernfs: Add KERNFS_REMOVING flags

bisection log:  https://syzkaller.appspot.com/x/bisect.txt?x=106731ee880000
final oops:     https://syzkaller.appspot.com/x/report.txt?x=126731ee880000
console output: https://syzkaller.appspot.com/x/log.txt?x=146731ee880000

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+2fdf66e68f5f882c1074@syzkaller.appspotmail.com
Fixes: c25491747b21 ("kernfs: Add KERNFS_REMOVING flags")

------------[ cut here ]------------
WARNING: CPU: 1 PID: 3608 at fs/kernfs/dir.c:36 kernfs_find_and_get_node_by_id+0x1f0/0x270 fs/kernfs/dir.c:708
Modules linked in:
CPU: 1 PID: 3608 Comm: syz-executor714 Not tainted 6.1.0-rc3-syzkaller-00152-gf2f32f8af2b0 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/11/2022
RIP: 0010:kernfs_active fs/kernfs/dir.c:36 [inline]
RIP: 0010:kernfs_find_and_get_node_by_id+0x1f0/0x270 fs/kernfs/dir.c:708
Code: e8 25 fc 29 08 4c 89 f0 5b 41 5c 41 5e 41 5f 5d c3 e8 94 c9 74 ff e9 35 ff ff ff e8 8a c9 74 ff e9 2b ff ff ff e8 80 c9 74 ff <0f> 0b e9 2c ff ff ff 48 c7 c1 d4 e8 0d 8e 80 e1 07 80 c1 03 38 c1
RSP: 0018:ffffc90003cdfb58 EFLAGS: 00010293
RAX: ffffffff821316a0 RBX: 0000000000000000 RCX: ffff88802937d7c0
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: dffffc0000000000 R08: ffffffff821315ab R09: fffff5200079bf5c
R10: fffff5200079bf5d R11: 1ffff9200079bf5c R12: dffffc0000000000
R13: 0000000000000002 R14: ffff8881400f4570 R15: 0000000000000005
FS:  00005555572ef300(0000) GS:ffff8880b9b00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000020000000 CR3: 000000007806e000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 __kernfs_fh_to_dentry fs/kernfs/mount.c:102 [inline]
 kernfs_fh_to_dentry+0x129/0x1d0 fs/kernfs/mount.c:128
 exportfs_decode_fh_raw+0x115/0x600 fs/exportfs/expfs.c:435
 exportfs_decode_fh+0x38/0x70 fs/exportfs/expfs.c:575
 do_handle_to_path fs/fhandle.c:152 [inline]
 handle_to_path fs/fhandle.c:207 [inline]
 do_handle_open+0x485/0x950 fs/fhandle.c:223
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd
RIP: 0033:0x7f3991d2bbe9
Code: 28 c3 e8 2a 14 00 00 66 2e 0f 1f 84 00 00 00 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 c0 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fff8481e4e8 EFLAGS: 00000246 ORIG_RAX: 0000000000000130
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f3991d2bbe9
RDX: 0000000000000000 RSI: 00000000200000c0 RDI: 0000000000000005
RBP: 00007f3991cefd90 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007f3991cefe20
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
 </TASK>


---
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