bisecting fixing commit since dda0e2920330128e0dbdeb11c8f25031aa40b11c building syzkaller on 5ed396e666c7826bed46f06c4db1409376691fed testing commit dda0e2920330128e0dbdeb11c8f25031aa40b11c with gcc (GCC) 8.1.0 kernel signature: 3ac87b05258309aa79ae053eb316e25db409490a15ed1cbddc654b565d4b2ccd run #0: crashed: WARNING in corrupted run #1: crashed: WARNING in corrupted run #2: crashed: WARNING in ip_rt_bug run #3: crashed: WARNING in ip_rt_bug run #4: crashed: WARNING in ip_rt_bug 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 ip_rt_bug testing current HEAD 0c88e405c97ed1828443b67891e6d4bb6e56cd4e testing commit 0c88e405c97ed1828443b67891e6d4bb6e56cd4e with gcc (GCC) 8.1.0 kernel signature: 3faf62c4c6d2d45104267762eefb72b68e41c43885f841ae753ae0bae78ff5ba run #0: crashed: WARNING in corrupted run #1: crashed: WARNING in ip_rt_bug run #2: crashed: WARNING in ip_rt_bug run #3: crashed: WARNING in corrupted run #4: crashed: WARNING in corrupted run #5: crashed: WARNING in ip_rt_bug run #6: crashed: WARNING in corrupted run #7: crashed: WARNING in corrupted run #8: crashed: WARNING in ip_rt_bug run #9: crashed: WARNING in corrupted revisions tested: 2, total time: 25m38.666310655s (build: 18m59.874957962s, test: 5m31.774685826s) the crash still happens on HEAD commit msg: Linux 4.19.160 crash: WARNING in corrupted batman_adv: batadv0: Interface activated: batadv_slave_1 IPv6: ADDRCONF(NETDEV_CHANGE): batadv_slave_1: link becomes ready IPv6: ADDRCONF(NETDEV_CHANGE): veth1_to_batadv: link becomes ready syz-executor.2 uses obsolete (PF_INET,SOCK_PACKET) ------------[ cut here ]------------ WARNING: CPU: 1 PID: 7209 at net/ipv4/route.c:1240 ip_rt_bug+0x18/0x20 net/ipv4/route.c:1240 Kernel panic - not syncing: panic_on_warn set ... CPU: 1 PID: 7209 Comm: syz-executor.1 Not tainted 4.19.160-syzkaller #0 ------------[ cut here ]------------ Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x123/0x177 lib/dump_stack.c:118 panic+0x1cd/0x375 kernel/panic.c:186 WARNING: CPU: 0 PID: 7211 at net/ipv4/route.c:1240 ip_rt_bug+0x18/0x20 net/ipv4/route.c:1240 __warn.cold.8+0x1b/0x3e kernel/panic.c:541 Modules linked in: CPU: 0 PID: 7211 Comm: syz-executor.2 Not tainted 4.19.160-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:ip_rt_bug+0x18/0x20 net/ipv4/route.c:1240 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 11 a2 ff 48 c7 c7 40 dc c6 87 e8 28 dc 8d 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:ffff8881d97d7120 EFLAGS: 00010282 report_bug+0x1a4/0x200 lib/bug.c:186 RAX: 0000000000000024 RBX: ffff8881d8aeb3c0 RCX: 0000000000000001 fixup_bug arch/x86/kernel/traps.c:178 [inline] do_error_trap+0x200/0x350 arch/x86/kernel/traps.c:296 RDX: 0000000000000000 RSI: ffffffff87679600 RDI: ffffffff8a184960 RBP: ffff8881d97d7120 R08: ffffed103ed05079 R09: ffffed103ed05078 R10: ffffed103ed05078 R11: ffff8881f68283c7 R12: ffff8881e31ac080 R13: ffff8881e549f240 R14: ffff8881d8aeb418 R15: ffff8881d97d73d4 FS: 00007f08e5bd4700(0000) GS:ffff8881f6800000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f389d3ac06c CR3: 00000001d7371003 CR4: 00000000001606f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 do_invalid_op+0x1b/0x20 arch/x86/kernel/traps.c:316 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 invalid_op+0x14/0x20 arch/x86/entry/entry_64.S:1038 Call Trace: RIP: 0010:ip_rt_bug+0x18/0x20 net/ipv4/route.c:1240 dst_output include/net/dst.h:455 [inline] ip_local_out+0x74/0x130 net/ipv4/ip_output.c:125 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 11 a2 ff 48 c7 c7 40 dc c6 87 e8 28 dc 8d fb <0f> 0b 31 c0 5d c3 66 90 48 b8 00 00 00 00 00 fc ff df 48 89 fa 55 ip_send_skb+0x36/0xa0 net/ipv4/ip_output.c:1447 RSP: 0018:ffff8881d7967120 EFLAGS: 00010282 ip_push_pending_frames+0x4d/0x70 net/ipv4/ip_output.c:1467 RAX: 0000000000000024 RBX: ffff8881d71fb940 RCX: 0000000000000000 RDX: 0000000000000000 RSI: ffffffff87679600 RDI: ffffffff8a184960 icmp_push_reply+0x383/0x610 net/ipv4/icmp.c:398 RBP: ffff8881d7967120 R08: ffffed103ed25079 R09: ffffed103ed25078 __icmp_send+0xbc7/0x1930 net/ipv4/icmp.c:747 R10: ffffed103ed25078 R11: ffff8881f69283c7 R12: ffff8881e2c20140 R13: ffff8881e24e8d00 R14: ffff8881d71fb998 R15: ffff8881d79673d4 dst_output include/net/dst.h:455 [inline] ip_local_out+0x74/0x130 net/ipv4/ip_output.c:125 ip_send_skb+0x36/0xa0 net/ipv4/ip_output.c:1447 ip_push_pending_frames+0x4d/0x70 net/ipv4/ip_output.c:1467 icmp_push_reply+0x383/0x610 net/ipv4/icmp.c:398 __icmp_send+0xbc7/0x1930 net/ipv4/icmp.c:747 icmp_send include/net/icmp.h:47 [inline] ip_options_compile+0xad/0xc0 net/ipv4/ip_options.c:485 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 NF_HOOK include/linux/netfilter.h:289 [inline] ip_rcv+0xcb/0x2e0 net/ipv4/ip_input.c:524 icmp_send include/net/icmp.h:47 [inline] ip_options_compile+0xad/0xc0 net/ipv4/ip_options.c:485 ip_rcv_options net/ipv4/ip_input.c:282 [inline] ip_rcv_finish_core.isra.16+0x3b1/0x1830 net/ipv4/ip_input.c:356 __netif_receive_skb_one_core+0x112/0x1a0 net/core/dev.c:4954 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+0x1f/0x1b0 net/core/dev.c:5066 netif_receive_skb_internal+0xca/0x300 net/core/dev.c:5156 __netif_receive_skb_one_core+0x112/0x1a0 net/core/dev.c:4954 netif_receive_skb+0x3b/0x1e0 net/core/dev.c:5213 tun_rx_batched.isra.54+0x4d8/0x9c0 drivers/net/tun.c:1535 __netif_receive_skb+0x1f/0x1b0 net/core/dev.c:5066 netif_receive_skb_internal+0xca/0x300 net/core/dev.c:5156 tun_get_user+0x2606/0x48a0 drivers/net/tun.c:1966 netif_receive_skb+0x3b/0x1e0 net/core/dev.c:5213 tun_rx_batched.isra.54+0x4d8/0x9c0 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 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 __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 entry_SYSCALL_64_after_hwframe+0x49/0xbe vfs_write+0x150/0x4d0 fs/read_write.c:549 RIP: 0033:0x45c8c9 ksys_write+0x103/0x260 fs/read_write.c:599 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:00007f08e5bd3c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 00007f08e5bd46d4 RCX: 000000000045c8c9 RDX: 000000000000100c RSI: 0000000020000240 RDI: 0000000000000005 __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 RBP: 000000000076bf00 R08: 0000000000000000 R09: 0000000000000000 do_syscall_64+0xd0/0x4e0 arch/x86/entry/common.c:293 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff entry_SYSCALL_64_after_hwframe+0x49/0xbe R13: 0000000000000d0d R14: 00000000004cf3f9 R15: 000000000076bf0c irq event stamp: 2225 RIP: 0033:0x45c8c9 hardirqs last enabled at (2224): [] trace_hardirqs_on_thunk+0x1a/0x1c 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 hardirqs last disabled at (2225): [] trace_hardirqs_off_thunk+0x1a/0x1c RSP: 002b:00007f9619e22c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 softirqs last enabled at (2120): [] rcu_read_unlock include/linux/rcupdate.h:677 [inline] softirqs last enabled at (2120): [] tun_get_user+0x253e/0x48a0 drivers/net/tun.c:1913 softirqs last disabled at (2122): [] tun_rx_batched.isra.54+0x439/0x9c0 drivers/net/tun.c:1562 RAX: ffffffffffffffda RBX: 00007f9619e236d4 RCX: 000000000045c8c9 RDX: 000000000000100c RSI: 0000000020000240 RDI: 0000000000000005 ---[ end trace 2b1aae2c27ca86b6 ]--- RBP: 000000000076bf00 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff ------------[ cut here ]------------ R13: 0000000000000d0d R14: 00000000004cf3f9 R15: 000000000076bf0c Kernel Offset: disabled Rebooting in 86400 seconds..