bisecting fixing commit since dda0e2920330128e0dbdeb11c8f25031aa40b11c building syzkaller on 5ed396e666c7826bed46f06c4db1409376691fed testing commit dda0e2920330128e0dbdeb11c8f25031aa40b11c with gcc (GCC) 8.1.0 kernel signature: 38606bc7e2b0c76d5af5b6ceabcec10c3610b157dca8e226730ccd85c620951b run #0: crashed: WARNING in ip_rt_bug run #1: crashed: WARNING in corrupted run #2: crashed: WARNING in corrupted run #3: crashed: WARNING in ip_rt_bug run #4: crashed: WARNING in corrupted run #5: crashed: WARNING in ip_rt_bug run #6: crashed: WARNING in ip_rt_bug run #7: crashed: WARNING in ip_rt_bug run #8: crashed: WARNING in ip_rt_bug run #9: crashed: WARNING in ip_rt_bug testing current HEAD 13af6c74b14a883366e7702c40c52ff548096e7f testing commit 13af6c74b14a883366e7702c40c52ff548096e7f with gcc (GCC) 8.1.0 kernel signature: 1c977f00cf7e65c8ee5c8730e8a0f986b02fc8197e510cb1d00f22bf5c83af0d run #0: crashed: WARNING in ip_rt_bug run #1: crashed: WARNING in corrupted run #2: crashed: WARNING in corrupted run #3: crashed: WARNING in corrupted run #4: crashed: WARNING in corrupted run #5: crashed: WARNING in corrupted run #6: crashed: WARNING in ip_rt_bug run #7: crashed: WARNING in ip_rt_bug run #8: crashed: WARNING in ip_rt_bug run #9: crashed: WARNING in corrupted revisions tested: 2, total time: 26m49.346839907s (build: 19m10.396204276s, test: 6m5.547722018s) the crash still happens on HEAD commit msg: Linux 4.19.136 crash: WARNING in corrupted IPv6: ADDRCONF(NETDEV_CHANGE): batadv_slave_1: link becomes ready IPv6: ADDRCONF(NETDEV_CHANGE): veth1_to_batadv: link becomes ready syz-executor.3 uses obsolete (PF_INET,SOCK_PACKET) ------------[ cut here ]------------ ------------[ cut here ]------------ WARNING: CPU: 0 PID: 7888 at net/ipv4/route.c:1234 ip_rt_bug+0x18/0x20 net/ipv4/route.c:1234 WARNING: CPU: 1 PID: 7894 at net/ipv4/route.c:1234 ip_rt_bug+0x18/0x20 net/ipv4/route.c:1234 Kernel panic - not syncing: panic_on_warn set ... Modules linked in: CPU: 0 PID: 7888 Comm: syz-executor.2 Not tainted 4.19.136-syzkaller #0 CPU: 1 PID: 7894 Comm: syz-executor.0 Not tainted 4.19.136-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x123/0x177 lib/dump_stack.c:118 RIP: 0010:ip_rt_bug+0x18/0x20 net/ipv4/route.c:1234 Code: 48 8b 45 d8 e9 ed fe ff ff 66 0f 1f 84 00 00 00 00 00 55 48 89 d7 48 89 e5 e8 34 3b a2 ff 48 c7 c7 c0 b2 c6 87 e8 c8 1b 8f fb <0f> 0b 31 c0 5d c3 66 90 48 b8 00 00 00 00 00 fc ff df 48 89 fa 55 RSP: 0018:ffff88808ad47120 EFLAGS: 00010282 panic+0x1cd/0x375 kernel/panic.c:186 RAX: 0000000000000024 RBX: ffff88808afd7200 RCX: 0000000000000000 RDX: 0000000000000000 RSI: ffffffff87678f80 RDI: ffffffff8a18a960 RBP: ffff88808ad47120 R08: ffffed1015d65079 R09: ffffed1015d65078 __warn.cold.8+0x1b/0x3e kernel/panic.c:541 R10: ffffed1015d65078 R11: ffff8880aeb283c7 R12: ffff888097b400c0 R13: ffff88809acfa680 R14: ffff88808afd7258 R15: ffff88808ad473d4 report_bug+0x1a4/0x200 lib/bug.c:186 FS: 00007fe290f45700(0000) GS:ffff8880aeb00000(0000) knlGS:0000000000000000 fixup_bug arch/x86/kernel/traps.c:178 [inline] do_error_trap+0x200/0x350 arch/x86/kernel/traps.c:296 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f100af7ef60 CR3: 000000008ae6d000 CR4: 00000000001406e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: dst_output include/net/dst.h:455 [inline] ip_local_out+0x74/0x130 net/ipv4/ip_output.c:124 ip_send_skb+0x36/0xa0 net/ipv4/ip_output.c:1446 ip_push_pending_frames+0x4d/0x70 net/ipv4/ip_output.c:1466 do_invalid_op+0x1b/0x20 arch/x86/kernel/traps.c:316 icmp_push_reply+0x383/0x610 net/ipv4/icmp.c:395 invalid_op+0x14/0x20 arch/x86/entry/entry_64.S:1038 __icmp_send+0xbc7/0x1930 net/ipv4/icmp.c:744 RIP: 0010:ip_rt_bug+0x18/0x20 net/ipv4/route.c:1234 Code: 48 8b 45 d8 e9 ed fe ff ff 66 0f 1f 84 00 00 00 00 00 55 48 89 d7 48 89 e5 e8 34 3b a2 ff 48 c7 c7 c0 b2 c6 87 e8 c8 1b 8f fb <0f> 0b 31 c0 5d c3 66 90 48 b8 00 00 00 00 00 fc ff df 48 89 fa 55 RSP: 0018:ffff88808bc9f120 EFLAGS: 00010282 RAX: 0000000000000024 RBX: ffff88808b7278c0 RCX: 0000000000000000 RDX: 0000000000000000 RSI: ffffffff87678f80 RDI: ffffffff8a18a960 RBP: ffff88808bc9f120 R08: ffffed1015d45079 R09: ffffed1015d45078 R10: ffffed1015d45078 R11: ffff8880aea283c7 R12: ffff888098678080 R13: ffff88809878cc00 R14: ffff88808b727918 R15: ffff88808bc9f3d4 dst_output include/net/dst.h:455 [inline] ip_local_out+0x74/0x130 net/ipv4/ip_output.c:124 icmp_send include/net/icmp.h:47 [inline] ip_options_compile+0xad/0xc0 net/ipv4/ip_options.c:485 ip_send_skb+0x36/0xa0 net/ipv4/ip_output.c:1446 ip_push_pending_frames+0x4d/0x70 net/ipv4/ip_output.c:1466 icmp_push_reply+0x383/0x610 net/ipv4/icmp.c:395 ip_rcv_options net/ipv4/ip_input.c:282 [inline] ip_rcv_finish_core.isra.16+0x3b1/0x1830 net/ipv4/ip_input.c:356 __icmp_send+0xbc7/0x1930 net/ipv4/icmp.c:744 ip_rcv_finish+0x104/0x270 net/ipv4/ip_input.c:412 NF_HOOK include/linux/netfilter.h:289 [inline] ip_rcv+0xcb/0x2e0 net/ipv4/ip_input.c:524 __netif_receive_skb_one_core+0x112/0x1a0 net/core/dev.c:4954 icmp_send include/net/icmp.h:47 [inline] ip_options_compile+0xad/0xc0 net/ipv4/ip_options.c:485 __netif_receive_skb+0x1f/0x1b0 net/core/dev.c:5066 netif_receive_skb_internal+0xca/0x300 net/core/dev.c:5156 ip_rcv_options net/ipv4/ip_input.c:282 [inline] ip_rcv_finish_core.isra.16+0x3b1/0x1830 net/ipv4/ip_input.c:356 ip_rcv_finish+0x104/0x270 net/ipv4/ip_input.c:412 netif_receive_skb+0x3b/0x1e0 net/core/dev.c:5213 NF_HOOK include/linux/netfilter.h:289 [inline] ip_rcv+0xcb/0x2e0 net/ipv4/ip_input.c:524 tun_rx_batched.isra.54+0x4d2/0x9b0 drivers/net/tun.c:1535 __netif_receive_skb_one_core+0x112/0x1a0 net/core/dev.c:4954 tun_get_user+0x2606/0x48a0 drivers/net/tun.c:1966 __netif_receive_skb+0x1f/0x1b0 net/core/dev.c:5066 netif_receive_skb_internal+0xca/0x300 net/core/dev.c:5156 netif_receive_skb+0x3b/0x1e0 net/core/dev.c:5213 tun_rx_batched.isra.54+0x4d2/0x9b0 drivers/net/tun.c:1535 tun_get_user+0x2606/0x48a0 drivers/net/tun.c:1966 tun_chr_write_iter+0xaf/0x150 drivers/net/tun.c:1995 call_write_iter include/linux/fs.h:1821 [inline] new_sync_write fs/read_write.c:474 [inline] __vfs_write+0x443/0x890 fs/read_write.c:487 vfs_write+0x150/0x4d0 fs/read_write.c:549 ksys_write+0x103/0x260 fs/read_write.c:599 __do_sys_write fs/read_write.c:611 [inline] __se_sys_write fs/read_write.c:608 [inline] __x64_sys_write+0x6e/0xb0 fs/read_write.c:608 do_syscall_64+0xd0/0x4e0 arch/x86/entry/common.c:293 tun_chr_write_iter+0xaf/0x150 drivers/net/tun.c:1995 entry_SYSCALL_64_after_hwframe+0x49/0xbe call_write_iter include/linux/fs.h:1821 [inline] new_sync_write fs/read_write.c:474 [inline] __vfs_write+0x443/0x890 fs/read_write.c:487 RIP: 0033:0x45c8c9 Code: 2d b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 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 0f 83 fb b5 fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007fe290f44c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 00007fe290f456d4 RCX: 000000000045c8c9 vfs_write+0x150/0x4d0 fs/read_write.c:549 RDX: 000000000000100c RSI: 0000000020000240 RDI: 0000000000000005 ksys_write+0x103/0x260 fs/read_write.c:599 RBP: 000000000076bf00 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff R13: 0000000000000d0d R14: 00000000004cf3f9 R15: 000000000076bf0c irq event stamp: 1559 __do_sys_write fs/read_write.c:611 [inline] __se_sys_write fs/read_write.c:608 [inline] __x64_sys_write+0x6e/0xb0 fs/read_write.c:608 hardirqs last enabled at (1558): [] console_unlock+0xb9f/0xde0 kernel/printk/printk.c:2461 do_syscall_64+0xd0/0x4e0 arch/x86/entry/common.c:293 hardirqs last disabled at (1559): [] trace_hardirqs_off_thunk+0x1a/0x1c entry_SYSCALL_64_after_hwframe+0x49/0xbe softirqs last enabled at (1456): [] rcu_read_unlock include/linux/rcupdate.h:677 [inline] softirqs last enabled at (1456): [] tun_get_user+0x253e/0x48a0 drivers/net/tun.c:1913 softirqs last disabled at (1458): [] tun_rx_batched.isra.54+0x433/0x9b0 drivers/net/tun.c:1562 RIP: 0033:0x45c8c9 ---[ end trace c24a715b0a6dd02d ]--- Code: 2d b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 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 0f 83 fb b5 fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007f3110752c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 00007f31107536d4 RCX: 000000000045c8c9 RDX: 000000000000100c RSI: 0000000020000240 RDI: 0000000000000005 RBP: 000000000076bf00 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff R13: 0000000000000d0d R14: 00000000004cf3f9 R15: 000000000076bf0c Kernel Offset: disabled Rebooting in 86400 seconds..