------------[ cut here ]------------ WARNING: CPU: 0 PID: 4294 at net/ipv4/route.c:1274 kfree_skb include/linux/skbuff.h:1220 [inline] WARNING: CPU: 0 PID: 4294 at net/ipv4/route.c:1274 ip_rt_bug+0x25/0xf0 net/ipv4/route.c:1273 Modules linked in: CPU: 0 PID: 4294 Comm: kworker/0:4 Not tainted 6.1.135-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/19/2025 Workqueue: events pwq_unbound_release_workfn RIP: 0010:ip_rt_bug+0x25/0xf0 net/ipv4/route.c:1274 Code: 41 ff ff ff 90 41 57 41 56 41 55 41 54 53 48 89 d3 e8 df 99 eb f8 66 90 e8 d8 99 eb f8 48 89 df be 01 00 00 00 e8 7b b8 7e ff <0f> 0b 31 c0 5b 41 5c 41 5d 41 5e 41 5f c3 49 bd 00 00 00 00 00 fc RSP: 0018:ffffc90000007638 EFLAGS: 00010292 RAX: 9e7b3b62c7e64b00 RBX: ffff8880267efc80 RCX: 9e7b3b62c7e64b00 RDX: dffffc0000000000 RSI: ffffffff8a6bff00 RDI: ffffffff8abf0ea0 RBP: ffff888058639200 R08: dffffc0000000000 R09: fffffbfff2116e5b R10: fffffbfff2116e5b R11: 1ffffffff2116e5a R12: ffff888058639230 R13: ffff8880267efcd8 R14: ffff8880267efc80 R15: ffff8881452b8d00 FS: 0000000000000000(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000055e8fbda8131 CR3: 000000000c68e000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: dst_output include/net/dst.h:453 [inline] ip_local_out net/ipv4/ip_output.c:126 [inline] ip_send_skb+0x129/0x1c0 net/ipv4/ip_output.c:1599 __icmp_send+0xfbb/0x1320 net/ipv4/icmp.c:785 ipv4_send_dest_unreach net/ipv4/route.c:1254 [inline] ipv4_link_failure+0x65c/0xa10 net/ipv4/route.c:1261 dst_link_failure include/net/dst.h:423 [inline] arp_error_report+0x10e/0x160 net/ipv4/arp.c:296 neigh_invalidate+0x22c/0x450 net/core/neighbour.c:1059 neigh_timer_handler+0x911/0x1080 net/core/neighbour.c:1146 call_timer_fn+0x1a0/0x670 kernel/time/timer.c:1504 expire_timers kernel/time/timer.c:1549 [inline] __run_timers+0x525/0x7c0 kernel/time/timer.c:1820 run_timer_softirq+0x63/0xf0 kernel/time/timer.c:1833 handle_softirqs+0x2a1/0x920 kernel/softirq.c:578 __do_softirq kernel/softirq.c:612 [inline] invoke_softirq kernel/softirq.c:452 [inline] __irq_exit_rcu+0x12f/0x220 kernel/softirq.c:661 irq_exit_rcu+0x5/0x20 kernel/softirq.c:673 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1118 [inline] sysvec_apic_timer_interrupt+0xa0/0xc0 arch/x86/kernel/apic/apic.c:1118 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:691 RIP: 0010:__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:152 [inline] RIP: 0010:_raw_spin_unlock_irqrestore+0xa5/0x100 kernel/locking/spinlock.c:194 Code: 74 05 e8 4e 23 6e f7 48 c7 44 24 20 00 00 00 00 9c 8f 44 24 20 f6 44 24 21 02 75 4b f7 c3 00 02 00 00 74 01 fb bf 01 00 00 00 36 9e 3e f7 65 8b 05 37 73 e9 75 85 c0 74 3c 48 c7 04 24 0e 36 RSP: 0018:ffffc900047874c0 EFLAGS: 00000206 RAX: 9e7b3b62c7e64b00 RBX: 0000000000000a02 RCX: 9e7b3b62c7e64b00 RDX: dffffc0000000000 RSI: ffffffff8a6bff00 RDI: 0000000000000001 RBP: ffffc90004787548 R08: dffffc0000000000 R09: fffffbfff2116e4e R10: fffffbfff2116e4e R11: 1ffffffff2116e4d R12: dffffc0000000000 R13: dffffc0000000000 R14: ffff888079f327c0 R15: 1ffff920008f0e98 try_to_wake_up+0x64c/0x1080 kernel/sched/core.c:4229 wake_up_process kernel/sched/core.c:4361 [inline] wake_up_q+0x78/0xc0 kernel/sched/core.c:1009 __mutex_unlock_slowpath+0x406/0x6a0 kernel/locking/mutex.c:951 synchronize_rcu_expedited+0x6a2/0x830 kernel/rcu/tree_exp.h:982 synchronize_rcu+0x11c/0x380 kernel/rcu/tree.c:3576 lockdep_unregister_key+0x4ad/0x530 kernel/locking/lockdep.c:6374 wq_unregister_lockdep kernel/workqueue.c:3500 [inline] pwq_unbound_release_workfn+0x262/0x2b0 kernel/workqueue.c:3738 process_one_work+0x898/0x1160 kernel/workqueue.c:2292 worker_thread+0xaa2/0x1250 kernel/workqueue.c:2439 kthread+0x29d/0x330 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 ---------------- Code disassembly (best guess): 0: 74 05 je 0x7 2: e8 4e 23 6e f7 call 0xf76e2355 7: 48 c7 44 24 20 00 00 movq $0x0,0x20(%rsp) e: 00 00 10: 9c pushf 11: 8f 44 24 20 pop 0x20(%rsp) 15: f6 44 24 21 02 testb $0x2,0x21(%rsp) 1a: 75 4b jne 0x67 1c: f7 c3 00 02 00 00 test $0x200,%ebx 22: 74 01 je 0x25 24: fb sti 25: bf 01 00 00 00 mov $0x1,%edi * 2a: e8 36 9e 3e f7 call 0xf73e9e65 <-- trapping instruction 2f: 65 8b 05 37 73 e9 75 mov %gs:0x75e97337(%rip),%eax # 0x75e9736d 36: 85 c0 test %eax,%eax 38: 74 3c je 0x76 3a: 48 rex.W 3b: c7 .byte 0xc7 3c: 04 24 add $0x24,%al 3e: 0e (bad) 3f: 36 ss