------------[ cut here ]------------
WARNING: ./include/linux/ns_common.h:255 at __ns_ref_put include/linux/ns_common.h:255 [inline], CPU#1: syz.2.251/6566
WARNING: ./include/linux/ns_common.h:255 at put_mnt_ns+0x152/0x190 fs/namespace.c:6048, CPU#1: syz.2.251/6566
Modules linked in:
CPU: 1 UID: 0 PID: 6566 Comm: syz.2.251 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025
RIP: 0010:__ns_ref_put include/linux/ns_common.h:255 [inline]
RIP: 0010:put_mnt_ns+0x152/0x190 fs/namespace.c:6048
Code: 79 00 00 bf 01 00 00 00 89 ee e8 69 84 7d ff 85 ed 7e 1f e8 20 80 7d ff 5b 41 5e 41 5f 5d e9 05 1e 1b 09 cc e8 0f 80 7d ff 90 <0f> 0b 90 e9 33 ff ff ff e8 01 80 7d ff 4c 89 f7 be 03 00 00 00 5b
RSP: 0018:ffffc9011fb47a68 EFLAGS: 00010293
RAX: ffffffff82440021 RBX: ffff88801eb71000 RCX: ffff888057629e80
RDX: 0000000000000000 RSI: 00000000ffffffff RDI: 0000000000000000
RBP: 00000000ffffffff R08: ffff88801eb710bb R09: 1ffff11003d6e217
R10: dffffc0000000000 R11: ffffed1003d6e218 R12: dffffc0000000000
R13: 0000000000000009 R14: ffff88801eb710b8 R15: dffffc0000000000
FS:  0000000000000000(0000) GS:ffff888125fc2000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f1cbafb7460 CR3: 000000007a142000 CR4: 00000000003526f0
Call Trace:
 <TASK>
 free_nsproxy+0x46/0x560 kernel/nsproxy.c:192
 do_exit+0x6b8/0x2300 kernel/exit.c:969
 do_group_exit+0x21c/0x2d0 kernel/exit.c:1111
 get_signal+0x1285/0x1340 kernel/signal.c:3034
 arch_do_signal_or_restart+0x9a/0x7a0 arch/x86/kernel/signal.c:337
 __exit_to_user_mode_loop kernel/entry/common.c:41 [inline]
 exit_to_user_mode_loop+0x87/0x4f0 kernel/entry/common.c:75
 __exit_to_user_mode_prepare include/linux/irq-entry-common.h:226 [inline]
 syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:256 [inline]
 syscall_exit_to_user_mode_work include/linux/entry-common.h:159 [inline]
 syscall_exit_to_user_mode include/linux/entry-common.h:194 [inline]
 do_syscall_64+0x2e9/0xfa0 arch/x86/entry/syscall_64.c:100
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fa3045c1f85
Code: Unable to access opcode bytes at 0x7fa3045c1f5b.
RSP: 002b:00007fa305425f80 EFLAGS: 00000293 ORIG_RAX: 00000000000000e6
RAX: fffffffffffffdfc RBX: 00007fa3047e5fa0 RCX: 00007fa3045c1f85
RDX: 00007fa305425fc0 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 00007fa304611f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000000
R13: 00007fa3047e6038 R14: 00007fa3047e5fa0 R15: 00007ffd76cedfc8
 </TASK>