------------[ cut here ]------------ WARNING: ./include/linux/ns_common.h:255 at __ns_ref_put include/linux/ns_common.h:255 [inline], CPU#1: syz.1.1617/10236 WARNING: ./include/linux/ns_common.h:255 at put_mnt_ns+0x152/0x190 fs/namespace.c:6048, CPU#1: syz.1.1617/10236 Modules linked in: CPU: 1 UID: 0 PID: 10236 Comm: syz.1.1617 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 39 d9 7d ff 85 ed 7e 1f e8 f0 d4 7d ff 5b 41 5e 41 5f 5d e9 d5 a2 24 09 cc e8 df d4 7d ff 90 <0f> 0b 90 e9 33 ff ff ff e8 d1 d4 7d ff 4c 89 f7 be 03 00 00 00 5b RSP: 0018:ffffc9000ee4fa68 EFLAGS: 00010293 RAX: ffffffff8243fb51 RBX: ffff888027519000 RCX: ffff88802b438000 RDX: 0000000000000000 RSI: 00000000ffffffff RDI: 0000000000000000 RBP: 00000000ffffffff R08: ffff8880275190bb R09: 1ffff11004ea3217 R10: dffffc0000000000 R11: ffffed1004ea3218 R12: dffffc0000000000 R13: 0000000000000009 R14: ffff8880275190b8 R15: dffffc0000000000 FS: 0000000000000000(0000) GS:ffff888125b79000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f041bfa8286 CR3: 0000000029934000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000410 DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400 Call Trace: 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: 0033:0x7fa6b5bc1f85 Code: Unable to access opcode bytes at 0x7fa6b5bc1f5b. RSP: 002b:00007fa6b6aaaf80 EFLAGS: 00000293 ORIG_RAX: 00000000000000e6 RAX: fffffffffffffdfc RBX: 00007fa6b5de5fa0 RCX: 00007fa6b5bc1f85 RDX: 00007fa6b6aaafc0 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 00007fa6b5c11f91 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000000 R13: 00007fa6b5de6038 R14: 00007fa6b5de5fa0 R15: 00007ffd28a96898