------------[ cut here ]------------
WARNING: ./include/linux/ns_common.h:255 at __ns_ref_put include/linux/ns_common.h:255 [inline], CPU#0: syz.2.1031/9420
WARNING: ./include/linux/ns_common.h:255 at put_uts_ns include/linux/uts_namespace.h:37 [inline], CPU#0: syz.2.1031/9420
WARNING: ./include/linux/ns_common.h:255 at free_nsproxy+0x415/0x560 kernel/nsproxy.c:193, CPU#0: syz.2.1031/9420
Modules linked in:
CPU: 0 UID: 0 PID: 9420 Comm: syz.2.1031 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_uts_ns include/linux/uts_namespace.h:37 [inline]
RIP: 0010:free_nsproxy+0x415/0x560 kernel/nsproxy.c:193
Code: 85 ed 0f 8e be 00 00 00 e8 48 4d 33 00 48 8b 3d 71 71 32 11 48 89 de 5b 41 5c 41 5e 41 5f 5d e9 01 77 8e 00 e8 2c 4d 33 00 90 <0f> 0b 90 e9 ba fc ff ff e8 1e 4d 33 00 4c 89 ff be 03 00 00 00 e8
RSP: 0018:ffffc90002fa79f0 EFLAGS: 00010293
RAX: ffffffff818e8304 RBX: ffff88801d29b4e0 RCX: ffff888030361e80
RDX: 0000000000000000 RSI: 00000000ffffffff RDI: 0000000000000000
RBP: 00000000ffffffff R08: ffff888075ba852b R09: 1ffff1100eb750a5
R10: dffffc0000000000 R11: ffffed100eb750a6 R12: dffffc0000000000
R13: 0000000000000009 R14: ffff888075ba82d8 R15: ffff888075ba8528
FS:  0000000000000000(0000) GS:ffff888125a79000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f50463c3df0 CR3: 000000002544a000 CR4: 00000000003526f0
Call Trace:
 <TASK>
 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]
 ret_from_fork+0x61c/0xb30 arch/x86/kernel/process.c:167
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>