[....] Starting periodic command scheduler: cron[?25l[?1c7[ ok 8[?25h[?0c. [....] Starting OpenBSD Secure Shell server: sshd[ 24.178765] random: sshd: uninitialized urandom read (32 bytes read) [?25l[?1c7[ ok 8[?25h[?0c. Debian GNU/Linux 7 syzkaller ttyS0 syzkaller login: [ 29.703321] random: sshd: uninitialized urandom read (32 bytes read) [ 29.950119] random: sshd: uninitialized urandom read (32 bytes read) [ 30.531195] random: sshd: uninitialized urandom read (32 bytes read) [ 30.709227] random: sshd: uninitialized urandom read (32 bytes read) Warning: Permanently added '10.128.10.61' (ECDSA) to the list of known hosts. [ 36.367892] random: sshd: uninitialized urandom read (32 bytes read) executing program [ 36.472632] ------------[ cut here ]------------ [ 36.477435] kernel BUG at net/core/skbuff.c:1457! [ 36.482452] invalid opcode: 0000 [#1] SMP KASAN [ 36.487126] CPU: 1 PID: 4670 Comm: syz-executor648 Not tainted 4.19.0-rc1-next-20180831+ #53 [ 36.495700] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 36.505072] RIP: 0010:pskb_expand_head+0xc36/0x10e0 [ 36.510076] Code: 8b 85 20 fe ff ff 48 85 c0 0f 84 4f fe ff ff e8 90 ae 4e fc 4d 8d 74 24 ff e9 40 fe ff ff e8 81 ae 4e fc 0f 0b e8 7a ae 4e fc <0f> 0b e8 73 ae 4e fc 31 f6 31 ff e8 3a af 4e fc e9 70 fd ff ff 4c [ 36.529075] RSP: 0018:ffff8801b8276fc8 EFLAGS: 00010293 [ 36.534420] RAX: ffff8801b7c4a680 RBX: ffff8801be722340 RCX: ffffffff852e0eea [ 36.541690] RDX: 0000000000000000 RSI: ffffffff852e1976 RDI: 0000000000000005 [ 36.548962] RBP: ffff8801b82771c0 R08: ffff8801b7c4a680 R09: ffffed0037ce4484 [ 36.556214] R10: ffffed0037ce4484 R11: ffff8801be722427 R12: ffff8801be72240c [ 36.563465] R13: 0000000000000002 R14: dffffc0000000000 R15: 0000000000000000 [ 36.570730] FS: 00007f785670c700(0000) GS:ffff8801db100000(0000) knlGS:0000000000000000 [ 36.578967] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 36.584834] CR2: 0000000020000300 CR3: 00000001b8f6e000 CR4: 00000000001406e0 [ 36.592087] Call Trace: [ 36.594674] ? trace_hardirqs_on+0xbd/0x2c0 [ 36.598996] ? kasan_check_read+0x11/0x20 [ 36.603130] ? print_usage_bug+0xc0/0xc0 [ 36.607179] ? __pskb_copy_fclone+0xeb0/0xeb0 [ 36.611668] ? graph_lock+0x170/0x170 [ 36.615471] ? finish_task_switch+0x1d3/0x870 [ 36.619952] ? finish_task_switch+0x18a/0x870 [ 36.624433] ? __switch_to_asm+0x34/0x70 [ 36.628485] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 36.634006] ? graph_lock+0x170/0x170 [ 36.637805] __pskb_pull_tail+0x156/0x1880 [ 36.642024] ? skb_realloc_headroom+0x120/0x120 [ 36.646706] ? check_same_owner+0x340/0x340 [ 36.651028] ? rcu_note_context_switch+0x680/0x680 [ 36.655957] ip6_datagram_recv_specific_ctl+0x1945/0x1be0 [ 36.661485] ? ip6_datagram_recv_common_ctl+0x5c0/0x5c0 [ 36.666839] ? _copy_to_iter+0x1540/0x1540 [ 36.671101] ? kasan_check_read+0x11/0x20 [ 36.675249] ? rcu_is_watching+0x8c/0x150 [ 36.679381] ? rcu_pm_notify+0xc0/0xc0 [ 36.683257] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 36.688779] ? skb_copy_datagram_iter+0x257/0xb60 [ 36.693619] ? __sanitizer_cov_trace_const_cmp1+0x1a/0x20 [ 36.699144] ? ip6_datagram_recv_common_ctl+0x35a/0x5c0 [ 36.704492] ? ipv6_recv_rxpmtu+0x930/0x930 [ 36.708834] ? __sanitizer_cov_trace_const_cmp8+0x18/0x20 [ 36.714368] ? _copy_from_user+0xdf/0x150 [ 36.718510] ip6_datagram_recv_ctl+0x33/0x40 [ 36.722927] rawv6_recvmsg+0xc5f/0xea0 [ 36.726810] ? rawv6_rcv_skb+0x480/0x480 [ 36.730858] ? __sanitizer_cov_trace_const_cmp8+0x18/0x20 [ 36.736394] sock_common_recvmsg+0x13a/0x2a0 [ 36.740788] ? compat_sock_common_getsockopt+0x150/0x150 [ 36.746230] ? apparmor_socket_recvmsg+0x29/0x30 [ 36.750970] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 36.756492] ? security_socket_recvmsg+0x9b/0xc0 [ 36.761235] ? compat_sock_common_getsockopt+0x150/0x150 [ 36.766682] sock_recvmsg+0xd0/0x110 [ 36.770389] ? __sock_recv_ts_and_drops+0x420/0x420 [ 36.775390] ___sys_recvmsg+0x2b6/0x680 [ 36.779377] ? ___sys_sendmsg+0x930/0x930 [ 36.783512] ? do_futex+0x249/0x27d0 [ 36.787211] ? aa_af_perm+0x5a0/0x5a0 [ 36.791004] ? fget_raw+0x20/0x20 [ 36.794444] ? ___sys_sendmsg+0x313/0x930 [ 36.798595] ? graph_lock+0x170/0x170 [ 36.802386] ? __sanitizer_cov_trace_const_cmp8+0x18/0x20 [ 36.807908] ? poll_select_set_timeout+0x156/0x240 [ 36.812847] ? __sanitizer_cov_trace_const_cmp8+0x18/0x20 [ 36.818389] ? sockfd_lookup_light+0xc5/0x160 [ 36.822869] __sys_recvmmsg+0x303/0xbb0 [ 36.826854] ? __ia32_sys_recvmsg+0xb0/0xb0 [ 36.831163] ? lock_release+0x9f0/0x9f0 [ 36.835123] ? check_same_owner+0x340/0x340 [ 36.839431] ? ip6_datagram_connect+0x3a/0x50 [ 36.843916] ? __sanitizer_cov_trace_const_cmp8+0x18/0x20 [ 36.849439] ? _copy_from_user+0xdf/0x150 [ 36.853576] do_sys_recvmmsg+0xe3/0x190 [ 36.857534] ? __sys_recvmmsg+0xbb0/0xbb0 [ 36.861677] ? trace_hardirqs_on+0xbd/0x2c0 [ 36.865993] ? entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 36.871342] ? trace_hardirqs_off_caller+0x2b0/0x2b0 [ 36.876442] __x64_sys_recvmmsg+0xbe/0x150 [ 36.880672] do_syscall_64+0x1b9/0x820 [ 36.884551] ? entry_SYSCALL_64_after_hwframe+0x3e/0xbe [ 36.889898] ? syscall_return_slowpath+0x5e0/0x5e0 [ 36.894819] ? trace_hardirqs_on_caller+0x2b0/0x2b0 [ 36.899826] ? prepare_exit_to_usermode+0x3b0/0x3b0 [ 36.904828] ? recalc_sigpending_tsk+0x180/0x180 [ 36.909582] ? kasan_check_write+0x14/0x20 [ 36.913808] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 36.918637] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 36.923817] RIP: 0033:0x445c99 [ 36.927000] Code: e8 6c b6 02 00 48 83 c4 18 c3 0f 1f 80 00 00 00 00 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 2b 12 fc ff c3 66 2e 0f 1f 84 00 00 00 00 [ 36.945897] RSP: 002b:00007f785670bda8 EFLAGS: 00000246 ORIG_RAX: 000000000000012b [ 36.953588] RAX: ffffffffffffffda RBX: 00000000006dac38 RCX: 0000000000445c99 [ 36.960841] RDX: 0000000000000006 RSI: 0000000020006780 RDI: 0000000000000004 [ 36.968110] RBP: 00000000006dac30 R08: 0000000020006900 R09: 0000000000000000 [ 36.975363] R10: 0000000000000002 R11: 0000000000000246 R12: 00000000006dac3c [ 36.982616] R13: 0100000000000000 R14: 00007f785670c9c0 R15: 00000000006dad2c [ 36.989870] Modules linked in: [ 36.993056] Dumping ftrace buffer: [ 36.996586] (ftrace buffer empty) [ 37.000383] ---[ end trace 1d647a8828f29cb8 ]--- [ 37.005194] RIP: 0010:pskb_expand_head+0xc36/0x10e0 [ 37.010254] Code: 8b 85 20 fe ff ff 48 85 c0 0f 84 4f fe ff ff e8 90 ae 4e fc 4d 8d 74 24 ff e9 40 fe ff ff e8 81 ae 4e fc 0f 0b e8 7a ae 4e fc <0f> 0b e8 73 ae 4e fc 31 f6 31 ff e8 3a af 4e fc e9 70 fd ff ff 4c [ 37.029182] RSP: 0018:ffff8801b8276fc8 EFLAGS: 00010293 [ 37.034607] RAX: ffff8801b7c4a680 RBX: ffff8801be722340 RCX: ffffffff852e0eea [ 37.041910] RDX: 0000000000000000 RSI: ffffffff852e1976 RDI: 0000000000000005 [ 37.049202] RBP: ffff8801b82771c0 R08: ffff8801b7c4a680 R09: ffffed0037ce4484 [ 37.056507] R10: ffffed0037ce4484 R11: ffff8801be722427 R12: ffff8801be72240c [ 37.063806] R13: 0000000000000002 R14: dffffc0000000000 R15: 0000000000000000 [ 37.071120] FS: 00007f785670c700(0000) GS:ffff8801db100000(0000) knlGS:0000000000000000 [ 37.079380] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 37.085281] CR2: 0000000020000300 CR3: 00000001b8f6e000 CR4: 00000000001406e0 [ 37.092578] Kernel panic - not syncing: Fatal exception [ 37.098245] Dumping ftrace buffer: [ 37.101776] (ftrace buffer empty) [ 37.105469] Kernel Offset: disabled [ 37.109077] Rebooting in 86400 seconds..