------------[ cut here ]------------
WARNING: CPU: 1 PID: 16630 at fs/namespace.c:1187 mntput_no_expire+0xada/0xcd0 fs/namespace.c:1187
Modules linked in:
CPU: 1 PID: 16630 Comm: syz-executor.1 Not tainted 5.15.0-rc5-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 85 f9 eb ff 4c 8b 44 24 10 e9 9d fe ff ff e8 76 86 a4 ff <0f> 0b e9 19 fd ff ff e8 6a 86 a4 ff e8 95 58 66 07 31 ff 89 c5 89
RSP: 0018:ffffc900051479c8 EFLAGS: 00010293
RAX: 0000000000000000 RBX: 1ffff92000a28f3f RCX: 0000000000000000
RDX: ffff88807e74d580 RSI: ffffffff81d25f1a RDI: 0000000000000003
RBP: ffff888070783800 R08: 0000000000000000 R09: ffffffff8fd0e9ef
R10: ffffffff81d25c31 R11: 0000000000000000 R12: 0000000000000008
R13: ffffc90005147a18 R14: 00000000ffffffff R15: 0000000000000002
FS:  0000000000000000(0000) GS:ffff8880b9d00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f6869d189e0 CR3: 000000000b68e000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 mntput fs/namespace.c:1233 [inline]
 namespace_unlock+0x26b/0x410 fs/namespace.c:1452
 drop_collected_mounts fs/namespace.c:1935 [inline]
 put_mnt_ns fs/namespace.c:4344 [inline]
 put_mnt_ns+0x106/0x140 fs/namespace.c:4340
 free_nsproxy+0x43/0x4c0 kernel/nsproxy.c:191
 put_nsproxy include/linux/nsproxy.h:105 [inline]
 switch_task_namespaces+0xaf/0xd0 kernel/nsproxy.c:249
 do_exit+0xba9/0x2a30 kernel/exit.c:824
 do_group_exit+0x125/0x310 kernel/exit.c:922
 get_signal+0x47f/0x2160 kernel/signal.c:2868
 arch_do_signal_or_restart+0x2a9/0x1c40 arch/x86/kernel/signal.c:865
 handle_signal_work kernel/entry/common.c:148 [inline]
 exit_to_user_mode_loop kernel/entry/common.c:172 [inline]
 exit_to_user_mode_prepare+0x17d/0x290 kernel/entry/common.c:207
 __syscall_exit_to_user_mode_work kernel/entry/common.c:289 [inline]
 syscall_exit_to_user_mode+0x19/0x60 kernel/entry/common.c:300
 do_syscall_64+0x42/0xb0 arch/x86/entry/common.c:86
 entry_SYSCALL_64_after_hwframe+0x44/0xae
RIP: 0033:0x7f686c7c3a39
Code: Unable to access opcode bytes at RIP 0x7f686c7c3a0f.
RSP: 002b:00007f6869d18188 EFLAGS: 00000246 ORIG_RAX: 0000000000000110
RAX: fffffffffffffffc RBX: 00007f686c8c7020 RCX: 00007f686c7c3a39
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000048020000
RBP: 00007f686c81dc5f R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007ffff250e8df R14: 00007f6869d18300 R15: 0000000000022000