------------[ cut here ]------------
WARNING: CPU: 0 PID: 552 at fs/namespace.c:1187 mntput_no_expire+0xada/0xcd0 fs/namespace.c:1187
Modules linked in:
CPU: 0 PID: 552 Comm: syz-executor.4 Not tainted 5.15.0-rc1-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:mntput_no_expire+0xada/0xcd0 fs/namespace.c:1187
Code: 30 84 c0 0f 84 b9 fe ff ff 3c 03 0f 8f b1 fe ff ff 4c 89 44 24 10 e8 b5 f9 eb ff 4c 8b 44 24 10 e9 9d fe ff ff e8 06 9b a4 ff <0f> 0b e9 19 fd ff ff e8 fa 9a a4 ff e8 25 7b 63 07 31 ff 89 c5 89
RSP: 0018:ffffc90004c7fc38 EFLAGS: 00010293
RAX: 0000000000000000 RBX: 1ffff9200098ff8d RCX: 0000000000000000
RDX: ffff88804a91b900 RSI: ffffffff81d170aa RDI: 0000000000000003
RBP: ffff88801f3f3080 R08: 0000000000000000 R09: ffffffff8fcff92f
R10: ffffffff81d16dc1 R11: 0000000000000000 R12: 0000000000000008
R13: ffffc90004c7fc88 R14: 00000000fffffffe R15: 0000000000000002
FS:  00005555557f8400(0000) GS:ffff8880b9c00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fb8d8534f64 CR3: 0000000052295000 CR4: 00000000001506f0
DR0: 0000000020000280 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000600
Call Trace:
 mntput fs/namespace.c:1233 [inline]
 namespace_unlock+0x26b/0x410 fs/namespace.c:1452
 do_umount fs/namespace.c:1671 [inline]
 path_umount+0x797/0x1260 fs/namespace.c:1753
 ksys_umount fs/namespace.c:1776 [inline]
 __do_sys_umount fs/namespace.c:1781 [inline]
 __se_sys_umount fs/namespace.c:1779 [inline]
 __x64_sys_umount+0x159/0x180 fs/namespace.c:1779
 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+0x44/0xae
RIP: 0033:0x7f86986c0b67
Code: ff d0 48 89 c7 b8 3c 00 00 00 0f 05 48 c7 c1 bc ff ff ff f7 d8 64 89 01 48 83 c8 ff c3 66 0f 1f 44 00 00 b8 a6 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 bc ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fffb07caf58 EFLAGS: 00000202 ORIG_RAX: 00000000000000a6
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f86986c0b67
RDX: 00007fffb07cb02b RSI: 0000000000000002 RDI: 00007fffb07cb020
RBP: 00007fffb07cb020 R08: 00000000ffffffff R09: 00007fffb07cadf0
R10: 00005555557f98e3 R11: 0000000000000202 R12: 00007f8698718e80
R13: 00007fffb07cc0e0 R14: 00005555557f9810 R15: 00007fffb07cc120