------------[ cut here ]------------
WARNING: CPU: 1 PID: 16788 at net/ipv4/route.c:1259 kfree_skb include/linux/skbuff.h:1236 [inline]
WARNING: CPU: 1 PID: 16788 at net/ipv4/route.c:1259 ip_rt_bug+0x28/0x120 net/ipv4/route.c:1258
Modules linked in:
CPU: 1 PID: 16788 Comm: syz-executor.5 Not tainted 6.4.0-rc1-syzkaller-00149-g7eef636ecc58 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/28/2023
RIP: 0010:ip_rt_bug+0x28/0x120 net/ipv4/route.c:1259
Code: 00 00 f3 0f 1e fa 41 54 55 48 89 d5 53 48 83 ec 08 e8 8c d9 fa f8 66 90 e8 85 d9 fa f8 be 02 00 00 00 48 89 ef e8 58 66 7f ff <0f> 0b 48 83 c4 08 31 c0 5b 5d 41 5c c3 e8 66 d9 fa f8 48 8d 7d 10
RSP: 0018:ffffc900001e0890 EFLAGS: 00010246
RAX: 0000000000000000 RBX: ffff8880766b3980 RCX: 0000000000000100
RDX: ffff888044385940 RSI: ffffffff88896b68 RDI: 0000000000000000
RBP: ffff88802aec9b40 R08: 0000000000000000 R09: ffffffff91527d97
R10: 0000000000000001 R11: ffffffff8a12e924 R12: ffff888021b39d00
R13: ffff88802aec9b40 R14: 0000000000000000 R15: ffff88802aec9b98
FS:  00007f9b52c1e700(0000) GS:ffff8880b9900000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fe0d1b86058 CR3: 000000007b413000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <IRQ>
 dst_output include/net/dst.h:458 [inline]
 ip_local_out net/ipv4/ip_output.c:126 [inline]
 ip_send_skb net/ipv4/ip_output.c:1597 [inline]
 ip_push_pending_frames+0x129/0x2b0 net/ipv4/ip_output.c:1617
 icmp_push_reply+0x320/0x450 net/ipv4/icmp.c:389
 __icmp_send+0xba6/0x1450 net/ipv4/icmp.c:770
 ipv4_send_dest_unreach net/ipv4/route.c:1239 [inline]
 ipv4_link_failure+0x5a9/0x9e0 net/ipv4/route.c:1246
 dst_link_failure include/net/dst.h:437 [inline]
 arp_error_report+0xcb/0x1c0 net/ipv4/arp.c:296
 neigh_invalidate+0x20d/0x560 net/core/neighbour.c:1048
 neigh_timer_handler+0xc39/0x1010 net/core/neighbour.c:1135
 call_timer_fn+0x1a0/0x580 kernel/time/timer.c:1700
 expire_timers+0x29b/0x4b0 kernel/time/timer.c:1751
 __run_timers kernel/time/timer.c:2022 [inline]
 __run_timers kernel/time/timer.c:1995 [inline]
 run_timer_softirq+0x326/0x910 kernel/time/timer.c:2035
 __do_softirq+0x1d4/0x905 kernel/softirq.c:571
 invoke_softirq kernel/softirq.c:445 [inline]
 __irq_exit_rcu+0x114/0x190 kernel/softirq.c:650
 irq_exit_rcu+0x9/0x20 kernel/softirq.c:662
 sysvec_apic_timer_interrupt+0x97/0xc0 arch/x86/kernel/apic/apic.c:1106
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:645
RIP: 0010:__might_resched+0x6/0x580 kernel/sched/core.c:10108
Code: c7 ec a8 7a 8e e8 ba df 7e 00 e9 61 ff ff ff 48 c7 c7 ec a8 7a 8e e8 a9 df 7e 00 eb ab 0f 1f 80 00 00 00 00 f3 0f 1e fa 41 56 <41> 55 41 54 41 89 f4 55 48 89 fd 53 89 d3 48 83 ec 10 e8 23 23 b7
RSP: 0018:ffffc900038c7b70 EFLAGS: 00000246
RAX: 0000000000000000 RBX: 000000000007ffff RCX: 0000000000000000
RDX: 0000000000000000 RSI: 0000000000000123 RDI: ffffffff8b697220
RBP: ffffffff89524f90 R08: 0000000000000004 R09: 000000000007ffff
R10: 000000000000b67e R11: 1ffffffff18f47c1 R12: ffffffff8e41e1c0
R13: ffffc900038c7d08 R14: dffffc0000000000 R15: 000000000000b67e
 inet_twsk_purge+0x103/0x900 net/ipv4/inet_timewait_sock.c:291
 ops_exit_list+0x125/0x170 net/core/net_namespace.c:175
 setup_net+0x7fb/0xc50 net/core/net_namespace.c:362
 copy_net_ns+0x4ee/0x8e0 net/core/net_namespace.c:491
 create_new_namespaces+0x3f6/0xb20 kernel/nsproxy.c:110
 unshare_nsproxy_namespaces+0xc1/0x1f0 kernel/nsproxy.c:228
 ksys_unshare+0x449/0x920 kernel/fork.c:3444
 __do_sys_unshare kernel/fork.c:3515 [inline]
 __se_sys_unshare kernel/fork.c:3513 [inline]
 __x64_sys_unshare+0x31/0x40 kernel/fork.c:3513
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x39/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd
RIP: 0033:0x7f9b51e8c169
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 f1 19 00 00 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f9b52c1e168 EFLAGS: 00000246 ORIG_RAX: 0000000000000110
RAX: ffffffffffffffda RBX: 00007f9b51fac050 RCX: 00007f9b51e8c169
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000040000000
RBP: 00007f9b51ee7ca1 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007ffe09fe834f R14: 00007f9b52c1e300 R15: 0000000000022000
 </TASK>
----------------
Code disassembly (best guess), 3 bytes skipped:
   0:	7a 8e                	jp     0xffffff90
   2:	e8 ba df 7e 00       	callq  0x7edfc1
   7:	e9 61 ff ff ff       	jmpq   0xffffff6d
   c:	48 c7 c7 ec a8 7a 8e 	mov    $0xffffffff8e7aa8ec,%rdi
  13:	e8 a9 df 7e 00       	callq  0x7edfc1
  18:	eb ab                	jmp    0xffffffc5
  1a:	0f 1f 80 00 00 00 00 	nopl   0x0(%rax)
  21:	f3 0f 1e fa          	endbr64
  25:	41 56                	push   %r14
* 27:	41 55                	push   %r13 <-- trapping instruction
  29:	41 54                	push   %r12
  2b:	41 89 f4             	mov    %esi,%r12d
  2e:	55                   	push   %rbp
  2f:	48 89 fd             	mov    %rdi,%rbp
  32:	53                   	push   %rbx
  33:	89 d3                	mov    %edx,%ebx
  35:	48 83 ec 10          	sub    $0x10,%rsp
  39:	e8                   	.byte 0xe8
  3a:	23 23                	and    (%rbx),%esp
  3c:	b7                   	.byte 0xb7