[....] Starting file context maintaining daemon: restorecond[?25l[?1c7[ ok 8[?25h[?0c.
[....] Starting OpenBSD Secure Shell server: sshd[   20.746307] random: sshd: uninitialized urandom read (32 bytes read, 34 bits of entropy available)
[?25l[?1c7[ ok 8[?25h[?0c.
[   21.060799] random: sshd: uninitialized urandom read (32 bytes read, 34 bits of entropy available)
[   21.361218] random: sshd: uninitialized urandom read (32 bytes read, 35 bits of entropy available)

Debian GNU/Linux 7 syzkaller ttyS0

syzkaller login: [   22.315909] random: sshd: uninitialized urandom read (32 bytes read, 99 bits of entropy available)
[   22.493666] random: sshd: uninitialized urandom read (32 bytes read, 103 bits of entropy available)
Warning: Permanently added '10.128.0.53' (ECDSA) to the list of known hosts.
[   27.888273] random: sshd: uninitialized urandom read (32 bytes read, 112 bits of entropy available)
executing program
[   27.986925] ==================================================================
[   27.994327] BUG: KASAN: use-after-free in ip6_xmit+0x1a2c/0x1a70
[   28.000443] Read of size 8 at addr ffff8800b61d2658 by task syzkaller610588/3779
[   28.007939] 
[   28.009539] CPU: 0 PID: 3779 Comm: syzkaller610588 Not tainted 4.4.119-g024f962 #26
[   28.017296] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
[   28.026618]  0000000000000000 8677f3bc780bc4d7 ffff8801c4e3f7e0 ffffffff81d0402d
[   28.034582]  ffffea0002d87480 ffff8800b61d2658 0000000000000000 ffff8800b61d2658
[   28.042550]  0000000000000040 ffff8801c4e3f818 ffffffff814fe103 ffff8800b61d2658
[   28.050511] Call Trace:
[   28.053067]  [<ffffffff81d0402d>] dump_stack+0xc1/0x124
[   28.058403]  [<ffffffff814fe103>] print_address_description+0x73/0x260
[   28.065037]  [<ffffffff814fe615>] kasan_report+0x285/0x370
[   28.070631]  [<ffffffff833062ac>] ? ip6_xmit+0x1a2c/0x1a70
[   28.076231]  [<ffffffff814fe774>] __asan_report_load8_noabort+0x14/0x20
[   28.082952]  [<ffffffff833062ac>] ip6_xmit+0x1a2c/0x1a70
[   28.088375]  [<ffffffff814fa52c>] ? kfree+0xfc/0x300
[   28.093447]  [<ffffffff82e107ab>] ? pskb_expand_head+0x28b/0x980
[   28.099559]  [<ffffffff834597fe>] ? l2tp_xmit_skb+0xa5e/0xea0
[   28.105409]  [<ffffffff83304880>] ? ip6_finish_output2+0x1c60/0x1c60
[   28.111868]  [<ffffffff81230151>] ? __lock_is_held+0xa1/0xf0
[   28.117636]  [<ffffffff830c1ea1>] ? ipv4_dst_check+0x111/0x160
[   28.123572]  [<ffffffff82df2a98>] ? __sk_dst_check+0x148/0x260
[   28.129513]  [<ffffffff833c6ed6>] inet6_csk_xmit+0x246/0x480
[   28.135277]  [<ffffffff833c6d90>] ? inet6_csk_xmit+0x100/0x480
[   28.141217]  [<ffffffff833c6c90>] ? inet6_csk_update_pmtu+0x160/0x160
[   28.147776]  [<ffffffff83418b56>] ? udp6_set_csum+0x336/0xa80
[   28.153629]  [<ffffffff834599cf>] l2tp_xmit_skb+0xc2f/0xea0
[   28.159317]  [<ffffffff834664b4>] pppol2tp_sendmsg+0x584/0x7f0
[   28.165259]  [<ffffffff81b68a7f>] ? selinux_socket_sendmsg+0x3f/0x50
[   28.171720]  [<ffffffff83465f30>] ? pppol2tp_release+0x310/0x310
[   28.177831]  [<ffffffff82deb87a>] sock_sendmsg+0xca/0x110
[   28.183335]  [<ffffffff82dec7c8>] SYSC_sendto+0x2c8/0x340
[   28.188842]  [<ffffffff82dec500>] ? SYSC_connect+0x310/0x310
[   28.194606]  [<ffffffff82df418c>] ? lock_sock_nested+0xdc/0x120
[   28.200630]  [<ffffffff833b939a>] ? ip6_datagram_connect+0x3a/0x50
[   28.206920]  [<ffffffff831d0832>] ? inet_dgram_connect+0x172/0x1f0
[   28.213205]  [<ffffffff82dec402>] ? SYSC_connect+0x212/0x310
[   28.218972]  [<ffffffff810dc6f0>] ? __do_page_fault+0x380/0xa00
[   28.225002]  [<ffffffff837741d8>] ? retint_user+0x18/0x3c
[   28.230507]  [<ffffffff82deecc0>] SyS_sendto+0x40/0x50
[   28.235753]  [<ffffffff8377361f>] entry_SYSCALL_64_fastpath+0x1c/0x98
[   28.242296] 
[   28.243892] Allocated by task 3762:
[   28.247485]  [<ffffffff81035d96>] save_stack_trace+0x26/0x50
[   28.253369]  [<ffffffff814fd173>] save_stack+0x43/0xd0
[   28.258731]  [<ffffffff814fd43d>] kasan_kmalloc+0xad/0xe0
[   28.264351]  [<ffffffff814fda12>] kasan_slab_alloc+0x12/0x20
[   28.270232]  [<ffffffff814f90ea>] kmem_cache_alloc+0xba/0x290
[   28.276199]  [<ffffffff82e6945f>] dst_alloc+0x11f/0x1a0
[   28.281643]  [<ffffffff830c25e8>] rt_dst_alloc+0x78/0x430
[   28.287261]  [<ffffffff830cba7e>] __ip_route_output_key_hash+0xa4e/0x2390
[   28.294270]  [<ffffffff83195dd5>] __ip4_datagram_connect+0xa15/0x1150
[   28.300936]  [<ffffffff833b7ee9>] __ip6_datagram_connect+0x4d9/0x1950
[   28.307598]  [<ffffffff833b938f>] ip6_datagram_connect+0x2f/0x50
[   28.313830]  [<ffffffff831d082b>] inet_dgram_connect+0x16b/0x1f0
[   28.320062]  [<ffffffff82dec3a6>] SYSC_connect+0x1b6/0x310
[   28.325768]  [<ffffffff82deec14>] SyS_connect+0x24/0x30
[   28.331212]  [<ffffffff8377361f>] entry_SYSCALL_64_fastpath+0x1c/0x98
[   28.337872] 
[   28.339468] Freed by task 0:
[   28.342453]  [<ffffffff81035d96>] save_stack_trace+0x26/0x50
[   28.348334]  [<ffffffff814fd173>] save_stack+0x43/0xd0
[   28.353693]  [<ffffffff814fda92>] kasan_slab_free+0x72/0xc0
[   28.359486]  [<ffffffff814fa1d7>] kmem_cache_free+0xc7/0x320
[   28.365367]  [<ffffffff82e6a0fe>] dst_destroy+0x20e/0x330
[   28.370989]  [<ffffffff82e6a745>] dst_destroy_rcu+0x15/0x40
[   28.376785]  [<ffffffff812950d4>] rcu_process_callbacks+0x7f4/0x14a0
[   28.383361]  [<ffffffff83776b17>] __do_softirq+0x227/0xa38
[   28.389070] 
[   28.390665] The buggy address belongs to the object at ffff8800b61d2640
[   28.390665]  which belongs to the cache ip_dst_cache of size 208
[   28.403374] The buggy address is located 24 bytes inside of
[   28.403374]  208-byte region [ffff8800b61d2640, ffff8800b61d2710)
[   28.415124] The buggy address belongs to the page:
[   29.787225] PANIC: double fault, error_code: 0x0
[   29.792012] CPU: 0 PID: 3779 Comm: syzkaller610588 Not tainted 4.4.119-g024f962 #26
[   29.799773] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
[   29.809095] task: ffff8801c6b6e000 task.stack: ffff8801c4e38000
[   29.815118] RIP: 0010:[<ffffffff814907f4>]  [<ffffffff814907f4>] dump_page_badflags+0x4/0x250
[   29.823875] RSP: 0018:ffff880100000000  EFLAGS: 00010046
[   29.829291] RAX: ffff8801c6b6e000 RBX: ffffea0002d87480 RCX: ffffffff81490970
[   29.836541] RDX: 0000000000000000 RSI: ffffffff838a9060 RDI: ffffea0002d87480
[   29.843779] RBP: ffff880100000000 R08: 0000000000000001 R09: 0000000000000000
[   29.851016] R10: 0000000000000002 R11: fffffbfff0ad7e1e R12: 0000000000000000
[   29.858256] R13: ffffffff838a9060 R14: 0000000000000000 R15: 0000000000000000
[   29.865497] FS:  0000000001513880(0063) GS:ffff8801db200000(0000) knlGS:0000000000000000
[   29.873691] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[   29.879539] CR2: ffff8800fffffff8 CR3: 00000001c97ee000 CR4: 0000000000160670
[   29.886780] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[   29.894028] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[   29.901265] Stack:
[   29.903380] 
[   29.904974] Call Trace:
[   29.907524]  <UNK> 
[   29.909550] Code: e8 92 df 06 00 e9 83 fd ff ff e8 88 df 06 00 e9 50 fd ff ff e8 7e df 06 00 e9 1d fd ff ff 66 0f 1f 84 00 00 00 00 00 55 48 89 e5 <41> 57 41 56 41 55 49 89 f5 41 54 49 89 d4 53 48 89 fb 48 83 ec 
[   29.936551] Kernel panic - not syncing: Machine halted.
[   29.941884] CPU: 0 PID: 3779 Comm: syzkaller610588 Not tainted 4.4.119-g024f962 #26
[   29.949655] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
[   29.958983]  0000000000000000 8677f3bc780bc4d7 ffff8801db20ce38 ffffffff81d0402d
[   29.966961]  ffffffff838373a0 ffff8801db20cf10 ffffffff83808040 ffff880100000000
[   29.974924]  0000000000000000 ffff8801db20cf00 ffffffff8141aaea 0000000041b58ab3
[   29.982889] Call Trace:
[   29.985442]  <#DF>  [<ffffffff81d0402d>] dump_stack+0xc1/0x124
[   29.991515]  [<ffffffff8141aaea>] panic+0x1aa/0x388
[   29.996506]  [<ffffffff8141a940>] ? percpu_up_read.constprop.45+0xe1/0xe1
[   30.003407]  [<ffffffff8126a292>] ? vprintk_emit+0x242/0x850
[   30.009173]  [<ffffffff81490809>] ? dump_page_badflags+0x19/0x250
[   30.015375]  [<ffffffff8126a292>] ? vprintk_emit+0x242/0x850
[   30.021144]  [<ffffffff810caf6d>] df_debug+0x2d/0x30
[   30.026227]  [<ffffffff81012d2b>] do_double_fault+0x10b/0x210
[   30.032080]  [<ffffffff837746fd>] double_fault+0x2d/0x40
[   30.037510]  [<ffffffff81490970>] ? dump_page_badflags+0x180/0x250
[   30.043796]  [<ffffffff814907f4>] ? dump_page_badflags+0x4/0x250
[   30.049905]  <<EOE>>  <UNK> 
[   30.053457] Dumping ftrace buffer:
[   30.057308]    (ftrace buffer empty)
[   30.060988] Kernel Offset: disabled
[   30.064596] Rebooting in 86400 seconds..