[....] Starting file context maintaining daemon: restorecond[?25l[?1c7[1G[[32m ok [39;49m8[?25h[?0c. [....] Starting OpenBSD Secure Shell server: sshd[ 20.446826] random: sshd: uninitialized urandom read (32 bytes read, 34 bits of entropy available) [?25l[?1c7[1G[[32m ok [39;49m8[?25h[?0c. Debian GNU/Linux 7 syzkaller ttyS0 syzkaller login: [ 25.076396] random: sshd: uninitialized urandom read (32 bytes read, 40 bits of entropy available) [ 25.576700] random: sshd: uninitialized urandom read (32 bytes read, 41 bits of entropy available) [ 26.612887] random: sshd: uninitialized urandom read (32 bytes read, 124 bits of entropy available) [ 26.746333] random: nonblocking pool is initialized Warning: Permanently added '10.128.0.40' (ECDSA) to the list of known hosts. 2018/03/20 18:11:48 parsed 1 programs 2018/03/20 18:11:48 executed programs: 0 [ 32.489620] IPVS: Creating netns size=2552 id=1 [ 33.539645] ------------[ cut here ]------------ [ 33.544444] WARNING: CPU: 1 PID: 4059 at net/core/skbuff.c:4183 skb_try_coalesce+0xfa6/0x15f0() [ 33.553373] Kernel panic - not syncing: panic_on_warn set ... [ 33.553373] [ 33.560711] CPU: 1 PID: 4059 Comm: syz-executor0 Not tainted 4.4.120-gd63fdf6 #29 [ 33.568300] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 33.577623] 0000000000000000 664b567325976035 ffff8801db307228 ffffffff81d0408d [ 33.585602] ffffffff83843b40 ffff8801db307300 ffffffff83ca8de0 0000000000000009 [ 33.593578] 0000000000001057 ffff8801db3072f0 ffffffff8141ab2a 0000000041b58ab3 [ 33.601546] Call Trace: [ 33.604103] [] dump_stack+0xc1/0x124 [ 33.610183] [] panic+0x1aa/0x388 [ 33.615169] [] ? percpu_up_read.constprop.45+0xe1/0xe1 [ 33.622064] [] ? pm_qos_get_value.part.4+0xb/0xb [ 33.628438] [] ? tcp_ack+0x2138/0x4660 [ 33.633944] [] ? tcp_rcv_established+0x5ee/0x2230 [ 33.640408] [] ? tcp_v6_do_rcv+0x42d/0x1470 [ 33.646352] [] ? warn_slowpath_common+0x10a/0x140 [ 33.652811] [] warn_slowpath_common+0x125/0x140 [ 33.659198] [] ? skb_try_coalesce+0xfa6/0x15f0 [ 33.665398] [] warn_slowpath_null+0x29/0x30 [ 33.671340] [] skb_try_coalesce+0xfa6/0x15f0 [ 33.677376] [] tcp_try_coalesce+0x15c/0x4d0 [ 33.683329] [] ? tcp_parse_options+0x970/0x970 [ 33.689532] [] ? sk_reset_timer+0x37/0x40 [ 33.695300] [] tcp_queue_rcv+0x127/0x720 [ 33.700980] [] tcp_data_queue+0xd9b/0x48e0 [ 33.706833] [] ? tcp_rcv_space_adjust+0x400/0x400 [ 33.713294] [] ? tcp_sendpage+0x15d0/0x1830 [ 33.719235] [] ? tcp_send_challenge_ack.isra.51+0x1b0/0x1b0 [ 33.726564] [] ? tcp_validate_incoming+0x721/0xfa0 [ 33.733111] [] tcp_rcv_established+0x7ca/0x2230 [ 33.739733] [] ? rt6_check+0x114/0x250 [ 33.745243] [] ? tcp_validate_incoming+0xfa0/0xfa0 [ 33.751789] [] ? rt6_check+0x15b/0x250 [ 33.757294] [] ? ip6_mtu+0x340/0x340 [ 33.762626] [] ? ip6_dst_check+0x16e/0x2c0 [ 33.768480] [] tcp_v6_do_rcv+0x42d/0x1470 [ 33.774252] [] ? tcp_prequeue+0x5b0/0xe10 [ 33.780024] [] tcp_v6_rcv+0x1b8d/0x2800 [ 33.785619] [] ? raw6_local_deliver+0x452/0x7e0 [ 33.791914] [] ip6_input_finish+0x329/0x1540 [ 33.797943] [] ? ip6_rcv_finish+0x630/0x630 [ 33.803880] [] ip6_input+0x106/0x200 [ 33.809216] [] ? ipv6_rcv+0x1e60/0x1e60 [ 33.814809] [] ? ip6_rcv_finish+0x630/0x630 [ 33.820757] [] ? nf_iterate+0x220/0x220 [ 33.826351] [] ip6_rcv_finish+0x138/0x630 [ 33.832118] [] ipv6_rcv+0x1055/0x1e60 [ 33.837539] [] ? ipv6_rcv+0xf7/0x1e60 [ 33.842962] [] ? ip6_input_finish+0x1540/0x1540 [ 33.849249] [] ? ip6_make_skb+0x3f0/0x3f0 [ 33.855017] [] ? ip6_input_finish+0x1540/0x1540 [ 33.861312] [] __netif_receive_skb_core+0xa59/0x28f0 [ 33.868036] [] ? debug_check_no_locks_freed+0x2c0/0x2c0 [ 33.875021] [] ? dev_cpu_callback+0x670/0x670 [ 33.881139] [] ? check_preemption_disabled+0x3b/0x200 [ 33.887962] [] __netif_receive_skb+0x5b/0x1c0 [ 33.894077] [] process_backlog+0x213/0x690 [ 33.899932] [] ? process_backlog+0x1af/0x690 [ 33.905966] [] net_rx_action+0x373/0xe70 [ 33.911649] [] ? kvm_clock_read+0x23/0x40 [ 33.917420] [] ? napi_complete_done+0x1f0/0x1f0 [ 33.923707] [] ? check_preemption_disabled+0x3b/0x200 [ 33.930519] [] ? check_preemption_disabled+0x3b/0x200 [ 33.937331] [] __do_softirq+0x227/0xa38 [ 33.942925] [] ? release_sock+0x3be/0x510 [ 33.948694] [] do_softirq_own_stack+0x1c/0x30 [ 33.954807] [] do_softirq.part.17+0x54/0x60 [ 33.961480] [] __local_bh_enable_ip+0xbe/0xd0 [ 33.967592] [] _raw_spin_unlock_bh+0x30/0x40 [ 33.973629] [] release_sock+0x3be/0x510 [ 33.979225] [] tcp_sendpage+0xaff/0x1830 [ 33.984905] [] ? sk_stream_alloc_skb+0x5d0/0x5d0 [ 33.991285] [] ? inet_sendpage+0x203/0x500 [ 33.997143] [] ? sk_stream_alloc_skb+0x5d0/0x5d0 [ 34.003525] [] inet_sendpage+0x2d7/0x500 [ 34.009204] [] ? inet_sendpage+0x7b/0x500 [ 34.014969] [] ? inet_sendmsg+0x4c0/0x4c0 [ 34.020737] [] kernel_sendpage+0x8d/0xe0 [ 34.026417] [] sock_sendpage+0x8c/0xc0 [ 34.031925] [] ? page_cache_pipe_buf_release+0x70/0x70 [ 34.038819] [] ? kernel_sendpage+0xe0/0xe0 [ 34.044676] [] pipe_to_sendpage+0x264/0x320 [ 34.050615] [] ? direct_splice_actor+0x180/0x180 [ 34.056991] [] ? splice_from_pipe_next+0x2a4/0x380 [ 34.063535] [] __splice_from_pipe+0x2ff/0x6f0 [ 34.069649] [] ? direct_splice_actor+0x180/0x180 [ 34.076022] [] splice_from_pipe+0xf9/0x160 [ 34.081872] [] ? direct_splice_actor+0x180/0x180 [ 34.088244] [] ? splice_shrink_spd+0x60/0x60 [ 34.094280] [] generic_splice_sendpage+0x40/0x50 [ 34.100655] [] ? splice_from_pipe+0x160/0x160 [ 34.106770] [] direct_splice_actor+0x125/0x180 [ 34.112968] [] splice_direct_to_actor+0x2d2/0x830 [ 34.119428] [] ? generic_pipe_buf_nosteal+0x10/0x10 [ 34.126060] [] ? do_splice_to+0x140/0x140 [ 34.131826] [] ? security_file_permission+0x89/0x1e0 [ 34.138544] [] ? rw_verify_area+0x100/0x2f0 [ 34.144483] [] do_splice_direct+0x1a7/0x270 [ 34.150424] [] ? splice_direct_to_actor+0x830/0x830 [ 34.157053] [] ? rw_verify_area+0x100/0x2f0 [ 34.162989] [] do_sendfile+0x54c/0xd30 [ 34.168492] [] ? __compat_sys_pwritev64+0xf0/0xf0 [ 34.174954] [] ? __might_fault+0xe4/0x1d0 [ 34.180719] [] ? __might_fault+0x114/0x1d0 [ 34.186572] [] compat_SyS_sendfile+0xd1/0x160 [ 34.192682] [] ? SyS_sendfile64+0x150/0x150 [ 34.198621] [] ? vmacache_update+0xfe/0x130 [ 34.204563] [] ? do_fast_syscall_32+0xd7/0x8a0 [ 34.210771] [] ? SyS_sendfile64+0x150/0x150 [ 34.216711] [] do_fast_syscall_32+0x321/0x8a0 [ 34.222829] [] sysenter_flags_fixed+0xd/0x17 [ 34.229433] Dumping ftrace buffer: [ 34.233041] (ftrace buffer empty) [ 34.236724] Kernel Offset: disabled [ 34.240372] Rebooting in 86400 seconds..