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WARNING: CPU: 1 PID: 8751 at net/ipv4/route.c:1269 ip_rt_bug+0x2c/0x110
Modules linked in:
CPU: 1 UID: 0 PID: 8751 Comm: syz.2.862 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.2-debian-1.16.2-1 04/01/2014
RIP: 0010:ip_rt_bug+0x2c/0x110
Code: 1e fa 41 57 41 56 41 55 41 54 53 48 89 d3 e8 eb 5b d5 f7 66 90 e8 e4 5b d5 f7 31 ff 48 89 de ba 02 00 00 00 e8 75 92 70 ff 90 <0f> 0b 90 31 c0 5b 41 5c 41 5d 41 5e 41 5f e9 d1 58 92 01 cc f3 0f
RSP: 0018:ffffc900067b7180 EFLAGS: 00010286
RAX: a122827959393900 RBX: ffff88810a1d0300 RCX: a122827959393900
RDX: 0000000000000002 RSI: ffffffff8d9b8241 RDI: ffffffff8be33880
RBP: 0000000000000001 R08: ffffffff8fa39037 R09: 1ffffffff1f47206
R10: dffffc0000000000 R11: fffffbfff1f47207 R12: dffffc0000000000
R13: dffffc0000000000 R14: ffff88810a1d0300 R15: ffff888104c42300
FS:  00007fd71e5fc6c0(0000) GS:ffff8881a3c18000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000000 CR3: 0000000110b94000 CR4: 00000000000006f0
Call Trace:
 <TASK>
 ip_push_pending_frames+0xbe/0x150
 __icmp_send+0xf87/0x12d0
 ip_options_compile+0x80/0xb0
 ip_rcv_finish_core+0xaa2/0x1c00
 ip_rcv_finish+0x14c/0x2f0
 NF_HOOK+0x30c/0x3a0
 __netif_receive_skb+0x143/0x380
 netif_receive_skb+0x1cb/0x790
 tun_rx_batched+0x1b9/0x730
 tun_get_user+0x2aa2/0x3e20
 tun_chr_write_iter+0x113/0x200
 vfs_write+0x5c9/0xb30
 ksys_write+0x145/0x250
 do_syscall_64+0xfa/0x3b0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fd71d78d69f
Code: 89 54 24 18 48 89 74 24 10 89 7c 24 08 e8 f9 92 02 00 48 8b 54 24 18 48 8b 74 24 10 41 89 c0 8b 7c 24 08 b8 01 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 31 44 89 c7 48 89 44 24 08 e8 4c 93 02 00 48
RSP: 002b:00007fd71e5fc000 EFLAGS: 00000293 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007fd71d9c5fa0 RCX: 00007fd71d78d69f
RDX: 0000000000000042 RSI: 0000200000000000 RDI: 00000000000000c8
RBP: 00007fd71d811e19 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000042 R11: 0000000000000293 R12: 0000000000000000
R13: 00007fd71d9c6038 R14: 00007fd71d9c5fa0 R15: 00007ffc1ad94368
 </TASK>
