IPv6: ADDRCONF(NETDEV_UP): bond0: link is not ready
8021q: adding VLAN 0 to HW filter on device bond0
IPv6: ADDRCONF(NETDEV_UP): veth0: link is not ready
IPv6: ADDRCONF(NETDEV_CHANGE): veth0: link becomes ready
==================================================================
BUG: KASAN: use-after-free in ip6_dst_idev include/net/ip6_fib.h:192 [inline]
BUG: KASAN: use-after-free in ip6_xmit+0x1f76/0x2260 net/ipv6/ip6_output.c:264
Read of size 8 at addr ffff8801c779c018 by task syzkaller308484/4032

CPU: 0 PID: 4032 Comm: syzkaller308484 Not tainted 4.16.0-rc4+ #349
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:17 [inline]
 dump_stack+0x194/0x24d lib/dump_stack.c:53
 print_address_description+0x73/0x250 mm/kasan/report.c:256
 kasan_report_error mm/kasan/report.c:354 [inline]
 kasan_report+0x23c/0x360 mm/kasan/report.c:412
 __asan_report_load8_noabort+0x14/0x20 mm/kasan/report.c:433
 ip6_dst_idev include/net/ip6_fib.h:192 [inline]
 ip6_xmit+0x1f76/0x2260 net/ipv6/ip6_output.c:264
 inet6_csk_xmit+0x2fc/0x580 net/ipv6/inet6_connection_sock.c:139
 l2tp_xmit_core net/l2tp/l2tp_core.c:1053 [inline]
 l2tp_xmit_skb+0x105f/0x1410 net/l2tp/l2tp_core.c:1148
 pppol2tp_sendmsg+0x470/0x670 net/l2tp/l2tp_ppp.c:341
 sock_sendmsg_nosec net/socket.c:630 [inline]
 sock_sendmsg+0xca/0x110 net/socket.c:640
 SYSC_sendto+0x361/0x5c0 net/socket.c:1747
 SyS_sendto+0x40/0x50 net/socket.c:1715
 do_syscall_64+0x281/0x940 arch/x86/entry/common.c:287
 entry_SYSCALL_64_after_hwframe+0x42/0xb7
RIP: 0033:0x442469
RSP: 002b:00007fff23c8ab28 EFLAGS: 00000212 ORIG_RAX: 000000000000002c
RAX: ffffffffffffffda RBX: 000000000000001a RCX: 0000000000442469
RDX: 0000000000000000 RSI: 0000000020001180 RDI: 0000000000000004
RBP: 00000000004a422d R08: 00000000200021c0 R09: 0000000000000080
R10: 0000000000040001 R11: 0000000000000212 R12: 00007fff23c8ac00
R13: 0000000000403490 R14: 0000000000000000 R15: 0000000000000000

The buggy address belongs to the page:
page:ffffea00071de700 count:0 mapcount:-127 mapping:0000000000000000 index:0xffff8801c779cd40
flags: 0x2fffc0000000000()
raw: 02fffc0000000000 0000000000000000 ffff8801c779cd40 00000000ffffff80
raw: ffffea00071da120 ffffea00071ca220 0000000000000002 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff8801c779bf00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff8801c779bf80: 00 00 00 00 00 fc fc fc fc fc fc fc fc fc fc fc
>ffff8801c779c000: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
                            ^
 ffff8801c779c080: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 ffff8801c779c100: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
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