[....] Starting OpenBSD Secure Shell server: sshd[ 19.470958] random: sshd: uninitialized urandom read (32 bytes read, 33 bits of entropy available) [ 19.551728] random: sshd: uninitialized urandom read (32 bytes read, 33 bits of entropy available) [?25l[?1c7[1G[[32m ok [39;49m8[?25h[?0c. [ 19.825439] random: sshd: uninitialized urandom read (32 bytes read, 34 bits of entropy available) [ 20.531846] random: sshd: uninitialized urandom read (32 bytes read, 73 bits of entropy available) [ 20.682314] random: sshd: uninitialized urandom read (32 bytes read, 76 bits of entropy available) Debian GNU/Linux 7 syzkaller ttyS0 Warning: Permanently added '10.128.0.43' (ECDSA) to the list of known hosts. syzkaller login: [ 26.087519] random: sshd: uninitialized urandom read (32 bytes read, 82 bits of entropy available) net.ipv6.conf.syz0.accept_dad = 0 net.ipv6.conf.syz0.router_solicitations = 0 RTNETLINK answers: Operation not supported RTNETLINK answers: Operation not supported RTNETLINK answers: Operation not supported RTNETLINK answers: Operation not supported Cannot find device "bridge0" Cannot find device "bridge0" Cannot find device "bridge0" Cannot find device "bridge0" Cannot find device "vcan0" Cannot find device "vcan0" Cannot find device "vcan0" Cannot find device "vcan0" RTNETLINK answers: Operation not supported Cannot find device "gre0" Cannot find device "gre0" Cannot find device "gre0" Cannot find device "gre0" Cannot find device "gretap0" Cannot find device "gretap0" Cannot find device "gretap0" Cannot find device "gretap0" Cannot find device "ip_vti0" Cannot find device "ip_vti0" Cannot find device "ip_vti0" Cannot find device "ip_vti0" Cannot find device "ip6_vti0" Cannot find device "ip6_vti0" Cannot find device "ip6_vti0" Cannot find device "ip6_vti0" Cannot find device "ip6tnl0" Cannot find device "ip6tnl0" Cannot find device "ip6tnl0" Cannot find device "ip6tnl0" Cannot find device "ip6gre0" Cannot find device "ip6gre0" Cannot find device "ip6gre0" Cannot find device "ip6gre0" Cannot find device "ip6gretap0" Cannot find device "ip6gretap0" Cannot find device "ip6gretap0" Cannot find device "ip6gretap0" Cannot find device "erspan0" Cannot find device "erspan0" Cannot find device "erspan0" Cannot find device "erspan0" [ 26.871911] ------------[ cut here ]------------ [ 26.876709] WARNING: CPU: 1 PID: 3776 at net/core/dev.c:2449 skb_warn_bad_offload+0x2af/0x390() [ 26.885539] syz0: caps=(0x00000080000048c1, 0x0000000000000000) len=90 data_len=0 gso_size=574 gso_type=5 ip_summed=0 [ 26.896270] Kernel panic - not syncing: panic_on_warn set ... [ 26.896270] [ 26.903600] CPU: 1 PID: 3776 Comm: syzkaller181840 Not tainted 4.4.115-g55a366596 #15 [ 26.911535] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 executing program [ 26.920863] 0000000000000000 654fdb29841461ec ffff8800aa27f3d8 ffffffff81d03d8d [ 26.928842] ffffffff83843a60 ffff8800aa27f4b0 ffffffff83caac60 0000000000000009 [ 26.936808] 0000000000000991 ffff8800aa27f4a0 ffffffff8141acba 0000000041b58ab3 [ 26.944783] Call Trace: [ 26.947342] [] dump_stack+0xc1/0x124 [ 26.952675] [] panic+0x1aa/0x388 [ 26.957660] [] ? percpu_up_read.constprop.45+0xe1/0xe1 [ 26.964556] [] ? warn_slowpath_common+0x10a/0x140 [ 26.971016] [] warn_slowpath_common+0x125/0x140 [ 26.977305] [] ? skb_warn_bad_offload+0x2af/0x390 [ 26.983764] [] warn_slowpath_fmt+0xc1/0x110 [ 26.989713] [] ? warn_slowpath_common+0x140/0x140 [ 26.996183] [] ? ___ratelimit+0x212/0x3e0 [ 27.001949] [] ? _raw_spin_unlock_irqrestore+0x45/0x70 [ 27.008842] [] ? ___ratelimit+0x53/0x3e0 [ 27.014519] [] skb_warn_bad_offload+0x2af/0x390 [ 27.020806] [] __skb_gso_segment+0x3b3/0x4a0 [ 27.026844] [] validate_xmit_skb.isra.101.part.102+0x44e/0x970 [ 27.034450] [] validate_xmit_skb_list+0xae/0x110 [ 27.040828] [] sch_direct_xmit+0x34f/0x760 [ 27.046685] [] ? dev_deactivate_queue.constprop.34+0x150/0x150 [ 27.054287] [] ? __dev_queue_xmit+0x1d5/0x1cc0 [ 27.060489] [] __dev_queue_xmit+0x148e/0x1cc0 [ 27.066605] [] ? __dev_queue_xmit+0x1d5/0x1cc0 [ 27.072817] [] ? netdev_pick_tx+0x310/0x310 [ 27.078769] [] ? tun_select_queue+0x1a1/0x380 [ 27.084882] [] ? tun_select_queue+0x1c8/0x380 [ 27.090994] [] ? tun_chr_ioctl+0x40/0x40 [ 27.096674] [] ? tun_chr_ioctl+0x40/0x40 [ 27.102353] [] dev_queue_xmit+0x17/0x20 [ 27.107947] [] packet_sendmsg+0x29b2/0x47e0 [ 27.113887] [] ? avc_has_perm_noaudit+0x460/0x460 [ 27.120350] [] ? debug_check_no_locks_freed+0x251/0x2c0 [ 27.127332] [] ? packet_cached_dev_get+0x200/0x200 [ 27.134068] [] ? selinux_file_send_sigiotask+0x310/0x310 [ 27.141138] [] ? avc_has_perm+0xb6/0x500 [ 27.146824] [] ? __might_fault+0xe4/0x1d0 [ 27.152782] [] ? selinux_socket_sendmsg+0x3f/0x50 [ 27.159246] [] ? security_socket_sendmsg+0x89/0xb0 [ 27.165797] [] ? packet_cached_dev_get+0x200/0x200 [ 27.172346] [] sock_sendmsg+0xca/0x110 [ 27.177849] [] SYSC_sendto+0x2c8/0x340 [ 27.183355] [] ? SYSC_connect+0x310/0x310 [ 27.189124] [] ? packet_poll+0x5c0/0x5c0 [ 27.194812] [] ? sock_has_perm+0x29f/0x400 [ 27.200665] [] ? selinux_file_send_sigiotask+0x310/0x310 [ 27.207745] [] ? selinux_netlbl_sock_rcv_skb+0x400/0x400 [ 27.214813] [] ? security_socket_setsockopt+0x89/0xb0 [ 27.221620] [] ? fput+0x20/0x150 [ 27.226604] [] ? compat_SyS_setsockopt+0x18a/0x290 [ 27.233157] [] ? scm_detach_fds_compat+0x3c0/0x3c0 [ 27.239707] [] SyS_sendto+0x40/0x50 [ 27.244952] [] ? SyS_getpeername+0x30/0x30 [ 27.250805] [] do_fast_syscall_32+0x314/0x890 [ 27.256925] [] sysenter_flags_fixed+0xd/0x17 [ 27.263523] Dumping ftrace buffer: [ 27.267052] (ftrace buffer empty) [ 27.270733] Kernel Offset: disabled [ 27.274328] Rebooting in 86400 seconds..