BUG: KASAN: stack-out-of-bounds in xfrm_state_find+0x303d/0x3170 net/xfrm/xfrm_state.c:1051
Read of size 4 at addr ffff8801d2257760 by task syzkaller539513/2990

CPU: 1 PID: 2990 Comm: syzkaller539513 Not tainted 4.14.0-rc5-next-20171018+ #36
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:16 [inline]
 dump_stack+0x194/0x257 lib/dump_stack.c:52
 print_address_description+0x73/0x250 mm/kasan/report.c:252
 kasan_report_error mm/kasan/report.c:351 [inline]
 kasan_report+0x25b/0x340 mm/kasan/report.c:409
 __asan_report_load4_noabort+0x14/0x20 mm/kasan/report.c:429
 xfrm_state_find+0x303d/0x3170 net/xfrm/xfrm_state.c:1051
 xfrm_tmpl_resolve_one net/xfrm/xfrm_policy.c:1388 [inline]
 xfrm_tmpl_resolve+0x309/0xc00 net/xfrm/xfrm_policy.c:1432
 xfrm_resolve_and_create_bundle+0x186/0x24a0 net/xfrm/xfrm_policy.c:1830
 xfrm_lookup+0xf0a/0x2540 net/xfrm/xfrm_policy.c:2141
 xfrm_lookup_route+0x39/0x1a0 net/xfrm/xfrm_policy.c:2259
 ip_route_output_flow+0x7c/0xa0 net/ipv4/route.c:2555
 udp_sendmsg+0x19b8/0x2cd0 net/ipv4/udp.c:1022
 udpv6_sendmsg+0x743/0x3380 net/ipv6/udp.c:1186
 inet_sendmsg+0x11f/0x5e0 net/ipv4/af_inet.c:763
 sock_sendmsg_nosec net/socket.c:632 [inline]
 sock_sendmsg+0xca/0x110 net/socket.c:642
 SYSC_sendto+0x352/0x5a0 net/socket.c:1749
 SyS_sendto+0x40/0x50 net/socket.c:1717
 entry_SYSCALL_64_fastpath+0x1f/0xbe
RIP: 0033:0x43ff99
RSP: 002b:00007ffe79365478 EFLAGS: 00000217 ORIG_RAX: 000000000000002c
RAX: ffffffffffffffda RBX: 00000000004002c8 RCX: 000000000043ff99
RDX: 0000000000000000 RSI: 0000000020a9f000 RDI: 0000000000000003
RBP: 0000000000000082 R08: 00000000204e3fe4 R09: 000000000000001c
R10: 0000000000000000 R11: 0000000000000217 R12: 0000000000401900
R13: 0000000000401990 R14: 0000000000000000 R15: 0000000000000000

The buggy address belongs to the page:
page:ffffea00074895c0 count:0 mapcount:0 mapping:          (null) index:0x0
flags: 0x200000000000000()
raw: 0200000000000000 0000000000000000 0000000000000000 00000000ffffffff
raw: 0000000000000000 0000000100000001 0000000000000000 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff8801d2257600: 00 f1 f1 f1 f1 04 f2 f2 f2 f2 f2 f2 f2 00 f2 f2
 ffff8801d2257680: f2 f2 f2 f2 f2 f8 f2 f2 f2 f2 f2 f2 f2 00 00 00
>ffff8801d2257700: 00 f2 f2 f2 f2 00 00 00 00 00 00 00 f2 f2 f2 f2
                                                       ^
 ffff8801d2257780: f2 00 00 00 00 00 00 00 00 00 f2 f2 f2 f3 f3 f3
 ffff8801d2257800: f3 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
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