------------[ cut here ]------------
WARNING: CPU: 0 PID: 17589 at fs/namespace.c:1186 mntput_no_expire+0xada/0xcd0 fs/namespace.c:1186
Modules linked in:
CPU: 0 PID: 17589 Comm: syz-executor.0 Not tainted 5.14.0-rc4-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:1186
Code: 30 84 c0 0f 84 b9 fe ff ff 3c 03 0f 8f b1 fe ff ff 4c 89 44 24 10 e8 45 fc eb ff 4c 8b 44 24 10 e9 9d fe ff ff e8 46 cb a5 ff <0f> 0b e9 19 fd ff ff e8 3a cb a5 ff e8 c5 5c 5a 07 31 ff 89 c5 89
RSP: 0018:ffffc9000b2f79b8 EFLAGS: 00010293
RAX: 0000000000000000 RBX: 1ffff9200165ef3d RCX: 0000000000000000
RDX: ffff8880763c0000 RSI: ffffffff81cfd01a RDI: 0000000000000003
RBP: ffff888035e4f680 R08: 0000000000000000 R09: ffffffff8fcd48af
R10: ffffffff81cfcd31 R11: 0000000000000000 R12: 0000000000000008
R13: ffffc9000b2f7a08 R14: 00000000ffffffff R15: 0000000000000002
FS:  0000000000000000(0000) GS:ffff8880b9c00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000001ffffe80 CR3: 000000001ce3a000 CR4: 00000000001526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 mntput fs/namespace.c:1232 [inline]
 namespace_unlock+0x26b/0x410 fs/namespace.c:1451
 drop_collected_mounts fs/namespace.c:1938 [inline]
 put_mnt_ns fs/namespace.c:4259 [inline]
 put_mnt_ns+0x106/0x140 fs/namespace.c:4255
 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+0xbcf/0x2a60 kernel/exit.c:824
 do_group_exit+0x125/0x310 kernel/exit.c:922
 get_signal+0x47f/0x2160 kernel/signal.c:2808
 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:209
 irqentry_exit_to_user_mode+0x5/0x40 kernel/entry/common.c:315
 exc_page_fault+0xc6/0x180 arch/x86/mm/fault.c:1534
 asm_exc_page_fault+0x1e/0x30 arch/x86/include/asm/idtentry.h:568
RIP: 0033:0x4665f1
Code: Unable to access opcode bytes at RIP 0x4665c7.
RSP: 002b:0000000020000280 EFLAGS: 00010217
RAX: 0000000000000000 RBX: 000000000056bf80 RCX: 00000000004665e9
RDX: 00000000200002c0 RSI: 0000000020000280 RDI: 0000000000020000
RBP: 00000000004bfcc4 R08: 0000000020000340 R09: 0000000000000000
R10: 0000000020000300 R11: 0000000000000246 R12: 000000000056bf80
R13: 0000000000a9fb1f R14: 00007faa83077300 R15: 0000000000022000