------------[ cut here ]------------ refcount_t: underflow; use-after-free. WARNING: CPU: 1 PID: 24 at lib/refcount.c:28 refcount_warn_saturate+0x11a/0x1d0 lib/refcount.c:28 Modules linked in: CPU: 1 UID: 0 PID: 24 Comm: kworker/1:0 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025 Workqueue: events xfrm_state_gc_task RIP: 0010:refcount_warn_saturate+0x11a/0x1d0 lib/refcount.c:28 Code: 80 b1 e2 8b e8 77 4e bb fc 90 0f 0b 90 90 eb d7 e8 6b af f7 fc c6 05 81 7b c5 0a 01 90 48 c7 c7 e0 b1 e2 8b e8 57 4e bb fc 90 <0f> 0b 90 90 eb b7 e8 4b af f7 fc c6 05 5e 7b c5 0a 01 90 48 c7 c7 RSP: 0018:ffffc900001e7888 EFLAGS: 00010246 RAX: 516864998ccbad00 RBX: 0000000000000003 RCX: ffff88801d680000 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000002 RBP: 0000000000000000 R08: ffffc900001e75a7 R09: 1ffff9200003ceb4 R10: dffffc0000000000 R11: fffff5200003ceb5 R12: dffffc0000000000 R13: ffff88802f119aa0 R14: ffff88802f1199e8 R15: ffff88802f119b90 FS: 0000000000000000(0000) GS:ffff888125d1a000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000055809cc3f950 CR3: 000000007eb98000 CR4: 00000000003526f0 Call Trace: __refcount_sub_and_test include/linux/refcount.h:400 [inline] __refcount_dec_and_test include/linux/refcount.h:432 [inline] refcount_dec_and_test include/linux/refcount.h:450 [inline] xfrm_state_put include/net/xfrm.h:928 [inline] __xfrm_state_delete+0xc73/0xde0 net/xfrm/xfrm_state.c:850 xfrm_state_delete net/xfrm/xfrm_state.c:863 [inline] xfrm_state_gc_destroy net/xfrm/xfrm_state.c:618 [inline] xfrm_state_gc_task+0x532/0x6d0 net/xfrm/xfrm_state.c:635 process_one_work kernel/workqueue.c:3236 [inline] process_scheduled_works+0xae1/0x17b0 kernel/workqueue.c:3319 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3400 kthread+0x70e/0x8a0 kernel/kthread.c:463 ret_from_fork+0x3f9/0x770 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245