------------[ cut here ]------------
WARNING: CPU: 1 PID: 8625 at fs/namespace.c:1187 mntput_no_expire+0xada/0xcd0 fs/namespace.c:1187
Modules linked in:
CPU: 1 PID: 8625 Comm: syz-executor.5 Not tainted 5.15.0-rc2-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 05 fa eb ff 4c 8b 44 24 10 e9 9d fe ff ff e8 d6 af a4 ff <0f> 0b e9 19 fd ff ff e8 ca af a4 ff e8 e5 ad 63 07 31 ff 89 c5 89
RSP: 0018:ffffc9000324fc20 EFLAGS: 00010216
RAX: 000000000001aaa7 RBX: 1ffff92000649f8a RCX: ffffc9000f461000
RDX: 0000000000040000 RSI: ffffffff81d15e2a RDI: 0000000000000003
RBP: ffff88807328b980 R08: 0000000000000000 R09: ffffffff8fcfb92f
R10: ffffffff81d15b41 R11: 0000000000000000 R12: 0000000000000008
R13: ffffc9000324fc70 R14: 00000000ffffffff R15: 0000000000000002
FS:  00007f13e8fc3700(0000) GS:ffff8880b9d00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ff9ce519018 CR3: 00000000535a1000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 mntput fs/namespace.c:1233 [inline]
 namespace_unlock+0x3ee/0x410 fs/namespace.c:1452
 unlock_mount fs/namespace.c:2274 [inline]
 do_new_mount_fc fs/namespace.c:2937 [inline]
 do_new_mount fs/namespace.c:2990 [inline]
 path_mount+0x159e/0x1fa0 fs/namespace.c:3318
 do_mount fs/namespace.c:3331 [inline]
 __do_sys_mount fs/namespace.c:3539 [inline]
 __se_sys_mount fs/namespace.c:3516 [inline]
 __x64_sys_mount+0x27f/0x300 fs/namespace.c:3516
 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: 0033:0x7f13eba4c709
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 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 bc ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f13e8fc3188 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00007f13ebb50f60 RCX: 00007f13eba4c709
RDX: 0000000020000740 RSI: 0000000020000400 RDI: 0000000000000000
RBP: 00007f13ebaa6cb4 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007ffcdc88c3ff R14: 00007f13e8fc3300 R15: 0000000000022000