------------[ cut here ]------------ WARNING: ./include/linux/ns_common.h:255 at __ns_ref_put include/linux/ns_common.h:255 [inline], CPU#0: syz.1.1549/10564 WARNING: ./include/linux/ns_common.h:255 at put_mnt_ns+0x152/0x190 fs/namespace.c:6048, CPU#0: syz.1.1549/10564 Modules linked in: CPU: 0 UID: 0 PID: 10564 Comm: syz.1.1549 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_mnt_ns+0x152/0x190 fs/namespace.c:6048 Code: 79 00 00 bf 01 00 00 00 89 ee e8 99 15 7e ff 85 ed 7e 1f e8 50 11 7e ff 5b 41 5e 41 5f 5d c3 cc cc cc cc cc e8 3f 11 7e ff 90 <0f> 0b 90 e9 33 ff ff ff e8 31 11 7e ff 4c 89 f7 be 03 00 00 00 5b RSP: 0018:ffffc900171bfaa8 EFLAGS: 00010293 RAX: ffffffff82434e41 RBX: ffff888040fe6000 RCX: ffff88802e6f8000 RDX: 0000000000000000 RSI: 00000000ffffffff RDI: 0000000000000000 RBP: 00000000ffffffff R08: ffff888040fe60bb R09: 1ffff110081fcc17 R10: dffffc0000000000 R11: ffffed10081fcc18 R12: dffffc0000000000 R13: 000000000000008b R14: ffff888040fe60b8 R15: dffffc0000000000 FS: 0000000000000000(0000) GS:ffff888125a82000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000001b30424000 CR3: 0000000075856000 CR4: 00000000003526f0 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 kernel/entry/common.c:75 [inline] __exit_to_user_mode_prepare include/linux/irq-entry-common.h:226 [inline] irqentry_exit_to_user_mode_prepare include/linux/irq-entry-common.h:270 [inline] irqentry_exit_to_user_mode include/linux/irq-entry-common.h:339 [inline] irqentry_exit+0x171/0x640 kernel/entry/common.c:196 exc_page_fault+0xab/0x100 arch/x86/mm/fault.c:1535 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:618 RIP: 0033:0x7fe390c4f6b7 Code: Unable to access opcode bytes at 0x7fe390c4f68d. RSP: 002b:00007fe391c4b120 EFLAGS: 00010202 RAX: 0000000000000000 RBX: 000000000000000b RCX: 00007fe390d8f6c9 RDX: 00007fe391c4b140 RSI: 00007fe391c4b270 RDI: 000000000000000b RBP: 00007fe390e11f91 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000000 R13: 00007fe390fe6038 R14: 00007fe390fe5fa0 R15: 00007ffc01772e88