[....] Starting enhanced syslogd: rsyslogd[?25l[?1c7[ ok 8[?25h[?0c. [....] Starting periodic command scheduler: cron[?25l[?1c7[ ok 8[?25h[?0c. [....] Starting OpenBSD Secure Shell server: sshd[ 11.152159] random: sshd: uninitialized urandom read (32 bytes read) [?25l[?1c7[ ok 8[?25h[?0c. Debian GNU/Linux 7 syzkaller ttyS0 syzkaller login: [ 14.952295] random: sshd: uninitialized urandom read (32 bytes read) [ 15.228783] random: sshd: uninitialized urandom read (32 bytes read) [ 15.340702] random: crng init done Warning: Permanently added '10.128.0.15' (ECDSA) to the list of known hosts. executing program [ 21.704794] ------------[ cut here ]------------ [ 21.709598] kernel BUG at net/core/skbuff.c:1208! [ 21.714419] invalid opcode: 0000 [#1] PREEMPT SMP KASAN [ 21.719876] Dumping ftrace buffer: [ 21.723402] (ftrace buffer empty) [ 21.727100] Modules linked in: [ 21.730387] CPU: 1 PID: 2241 Comm: syz-executor166 Not tainted 4.9.124+ #33 [ 21.737459] task: ffff8801c0d0df00 task.stack: ffff8801c83e8000 [ 21.743487] RIP: 0010:[] [] pskb_expand_head+0x834/0x8a0 [ 21.752248] RSP: 0018:ffff8801c83ef4e8 EFLAGS: 00010293 [ 21.757670] RAX: ffff8801c0d0df00 RBX: ffff8801c6eab140 RCX: 0000000002080020 [ 21.764984] RDX: 0000000000000000 RSI: ffffffff82246fa4 RDI: ffff8801c6eab21c [ 21.772235] RBP: ffff8801c83ef560 R08: 0000000000000018 R09: ffffed0039bea000 [ 21.779481] R10: ffffed0039bea000 R11: ffff8801cdf50003 R12: 00000000000000c0 [ 21.786770] R13: ffff8801c6eab204 R14: ffff8801d00160c0 R15: 0000000002080020 [ 21.794034] FS: 00007fcdf8975700(0000) GS:ffff8801db700000(0000) knlGS:0000000000000000 [ 21.802311] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 21.808173] CR2: 0000000020005700 CR3: 00000001cdee3000 CR4: 00000000001606b0 [ 21.815421] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 21.822682] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 21.829925] Stack: [ 21.832059] ffff8801c0d0e7b0 1ffff1003907dea0 ffffffff83a5a800 0000000041b58ab3 [ 21.840114] ffffffff82c30d68 ffffffff81202540 0000000000000296 ffff8801c83ef540 [ 21.848128] ffffffff8278b775 00000000c6eab140 ffff8801d0016000 0000000000000000 [ 21.856136] Call Trace: [ 21.858712] [] ? trace_hardirqs_on+0x10/0x10 [ 21.864756] [] ? _raw_spin_unlock_irqrestore+0x45/0x70 [ 21.871665] [] __pskb_pull_tail+0xc7/0x1240 [ 21.877613] [] ? debug_lockdep_rcu_enabled+0x77/0x90 [ 21.884389] [] ip6_datagram_recv_specific_ctl+0x1320/0x1580 [ 21.891727] [] ? check_stack_object+0x110/0x150 [ 21.898031] [] ? ip6_datagram_recv_common_ctl+0x3a0/0x3a0 [ 21.905196] [] ? copy_page_to_iter+0x2ca/0xb20 [ 21.911405] [] ? ip6_datagram_recv_common_ctl+0x27c/0x3a0 [ 21.918565] [] ? ipv6_recv_rxpmtu+0x790/0x790 [ 21.924685] [] ? skb_copy_datagram_iter+0x19e/0x910 [ 21.931490] [] ip6_datagram_recv_ctl+0x33/0x40 [ 21.937702] [] rawv6_recvmsg+0x8f4/0xac0 [ 21.943385] [] ? rawv6_bind+0x7c0/0x7c0 [ 21.948983] [] sock_common_recvmsg+0x112/0x1e0 [ 21.955188] [] ? compat_sock_common_getsockopt+0x150/0x150 [ 21.962442] [] ? selinux_socket_recvmsg+0x3f/0x50 [ 21.968912] [] ? security_socket_recvmsg+0x97/0xc0 [ 21.975468] [] ? compat_sock_common_getsockopt+0x150/0x150 [ 21.982723] [] sock_recvmsg+0xc6/0x110 [ 21.988238] [] ? __sock_recv_ts_and_drops+0x380/0x380 [ 21.995051] [] ___sys_recvmsg+0x242/0x510 [ 22.000826] [] ? ___sys_sendmsg+0x840/0x840 [ 22.006771] [] ? plist_del+0x14f/0x200 [ 22.012285] [] ? futex_wake+0x1aa/0x450 [ 22.017884] [] ? debug_lockdep_rcu_enabled+0x77/0x90 [ 22.024616] [] ? check_preemption_disabled+0x3b/0x170 [ 22.031438] [] ? check_preemption_disabled+0x3b/0x170 [ 22.038257] [] ? __fget+0x214/0x3d0 [ 22.043512] [] ? __fget_light+0x169/0x1f0 [ 22.049285] [] ? __fdget+0x18/0x20 [ 22.054450] [] ? sockfd_lookup_light+0xb6/0x160 [ 22.060744] [] __sys_recvmmsg+0x25d/0x6f0 [ 22.066518] [] ? exit_robust_list+0x220/0x220 [ 22.072648] [] ? SyS_recvmsg+0x50/0x50 [ 22.078166] [] ? trace_hardirqs_on+0x10/0x10 [ 22.084202] [] ? __fget_light+0x169/0x1f0 [ 22.090137] [] ? __fdget+0x18/0x20 [ 22.095301] [] ? debug_lockdep_rcu_enabled+0x77/0x90 [ 22.102030] [] SyS_recvmmsg+0xeb/0x1c0 [ 22.107539] [] ? __sys_recvmmsg+0x6f0/0x6f0 [ 22.113482] [] ? do_syscall_64+0x48/0x480 [ 22.119251] [] ? __sys_recvmmsg+0x6f0/0x6f0 [ 22.125195] [] do_syscall_64+0x19f/0x480 [ 22.130879] [] entry_SYSCALL_64_after_swapgs+0x5d/0xdb [ 22.137858] Code: ff ff 4c 89 f7 e8 bd f2 29 ff e9 c2 fb ff ff 4c 89 ff e8 10 f3 29 ff e9 3f fe ff ff e8 06 f3 29 ff e9 b1 fc ff ff e8 8c 58 0c ff <0f> 0b 48 8b 7d a0 e8 f1 f2 29 ff e9 34 fc ff ff 48 8b 7d a0 e8 [ 22.164710] RIP [] pskb_expand_head+0x834/0x8a0 [ 22.171122] RSP [ 22.174923] ---[ end trace f7d3267347d68cd0 ]--- [ 22.179673] Kernel panic - not syncing: Fatal exception [ 22.185332] Dumping ftrace buffer: [ 22.188848] (ftrace buffer empty) [ 22.192530] Kernel Offset: disabled [ 22.196130] Rebooting in 86400 seconds..