------------[ cut here ]------------
WARNING: ./include/linux/ns_common.h:255 at __ns_ref_put include/linux/ns_common.h:255 [inline], CPU#1: syz.1.2/5941
WARNING: ./include/linux/ns_common.h:255 at put_user_ns include/linux/user_namespace.h:189 [inline], CPU#1: syz.1.2/5941
WARNING: ./include/linux/ns_common.h:255 at put_cred_rcu+0x2c5/0x340 kernel/cred.c:61, CPU#1: syz.1.2/5941
Modules linked in:
CPU: 1 UID: 0 PID: 5941 Comm: syz.1.2 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
RIP: 0010:__ns_ref_put include/linux/ns_common.h:255 [inline]
RIP: 0010:put_user_ns include/linux/user_namespace.h:189 [inline]
RIP: 0010:put_cred_rcu+0x2c5/0x340 kernel/cred.c:61
Code: 5c 41 5d 41 5e 41 5f 5d e9 d8 e3 8d 00 e8 23 8e 32 00 4c 89 e7 be 03 00 00 00 e8 76 5a 00 03 e9 b8 fe ff ff e8 0c 8e 32 00 90 <0f> 0b 90 eb 9f e8 01 8e 32 00 4c 89 ff be 03 00 00 00 e8 54 5a 00
RSP: 0000:ffffc900046afae8 EFLAGS: 00010246
RAX: ffffffff818e9174 RBX: ffff888025fa7da0 RCX: ffff88802c101e80
RDX: 0000000000000100 RSI: 0000000000000001 RDI: 0000000000000000
RBP: 0000000000000001 R08: ffff88805953c193 R09: 1ffff1100b2a7832
R10: dffffc0000000000 R11: ffffed100b2a7833 R12: dffffc0000000000
R13: ffff888025fa7d00 R14: ffff88805953c000 R15: ffff88805953c190
FS:  00007fade69ab6c0(0000) GS:ffff888125fcc000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007faddc43e000 CR3: 000000001da84000 CR4: 00000000003526f0
Call Trace:
 <TASK>
 rcu_do_batch kernel/rcu/tree.c:2605 [inline]
 rcu_core+0xcab/0x1770 kernel/rcu/tree.c:2861
 handle_softirqs+0x27d/0x880 kernel/softirq.c:626
 __do_softirq kernel/softirq.c:660 [inline]
 invoke_softirq kernel/softirq.c:496 [inline]
 __irq_exit_rcu+0xca/0x1f0 kernel/softirq.c:727
 irq_exit_rcu+0x9/0x30 kernel/softirq.c:743
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1055 [inline]
 sysvec_apic_timer_interrupt+0x57/0xc0 arch/x86/kernel/apic/apic.c:1055
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0033:0x7fade5a509d0
Code: 49 8b 47 10 48 39 f0 72 6e 48 63 cd 48 01 c1 49 39 4f 08 72 4c 8d 4d ff 85 ed 74 33 66 0f 1f 44 00 00 48 39 f0 72 1b 4d 8b 07 <49> 89 c1 49 29 f1 47 0f b6 0c 08 45 84 c9 74 08 45 88 0c 00 49 8b
RSP: 002b:00007fade69aa4a0 EFLAGS: 00000206
RAX: 0000000000c3e54f RBX: 00007fade69aa540 RCX: 000000000000002e
RDX: 0000000000000055 RSI: 0000000000000001 RDI: 00007fade69aa5e0
RBP: 0000000000000102 R08: 00007faddb800000 R09: 0000000000000000
R10: 0000000000000000 R11: 00007fade69aa550 R12: 0000000000000001
R13: 00007fade5c2dc40 R14: 0000000000000000 R15: 00007fade69aa5e0
 </TASK>