BUG: KASAN: stack-out-of-bounds in xfrm_state_find+0x305b/0x3190 net/xfrm/xfrm_state.c:1051
Read of size 4 at addr ffff880038effaf8 by task syzkaller211418/3040

CPU: 3 PID: 3040 Comm: syzkaller211418 Not tainted 4.13.0-rc6-next-20170825+ #9
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Bochs 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+0x24e/0x340 mm/kasan/report.c:409
 __asan_report_load4_noabort+0x14/0x20 mm/kasan/report.c:429
 xfrm_state_find+0x305b/0x3190 net/xfrm/xfrm_state.c:1051
 xfrm_tmpl_resolve_one net/xfrm/xfrm_policy.c:1388 [inline]
 xfrm_tmpl_resolve+0x2fb/0xbd0 net/xfrm/xfrm_policy.c:1432
 xfrm_resolve_and_create_bundle+0x186/0x24b0 net/xfrm/xfrm_policy.c:1830
 xfrm_lookup+0xefb/0x2540 net/xfrm/xfrm_policy.c:2141
 xfrm_lookup_route+0x39/0x1a0 net/xfrm/xfrm_policy.c:2260
 ip_route_output_flow+0x7c/0xa0 net/ipv4/route.c:2549
 raw_sendmsg+0xc4b/0x38b0 net/ipv4/raw.c:633
 inet_sendmsg+0x11f/0x5e0 net/ipv4/af_inet.c:762
 sock_sendmsg_nosec net/socket.c:633 [inline]
 sock_sendmsg+0xca/0x110 net/socket.c:643
 SYSC_sendto+0x358/0x5a0 net/socket.c:1750
 SyS_sendto+0x40/0x50 net/socket.c:1718
 entry_SYSCALL_64_fastpath+0x1f/0xbe
RIP: 0033:0x435369
RSP: 002b:00007ffe850e38c8 EFLAGS: 00000217 ORIG_RAX: 000000000000002c
RAX: ffffffffffffffda RBX: ffffffffffffffff RCX: 0000000000435369
RDX: 0000000000000000 RSI: 000000002089b000 RDI: 0000000000000003
RBP: 0000000000000086 R08: 000000002000e000 R09: 0000000000000010
R10: 0000000000000000 R11: 0000000000000217 R12: 0000000000000000
R13: 0000000000401ce0 R14: 0000000000401d70 R15: 0000000000000000

The buggy address belongs to the page:
page:ffffea0000e3bfc0 count:0 mapcount:0 mapping:          (null) index:0x0
flags: 0x100000000000000()
raw: 0100000000000000 0000000000000000 0000000000000000 00000000ffffffff
raw: 0000000000000000 0000000100000001 0000000000000000 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff880038eff980: f2 f2 f2 f2 00 f2 f2 f2 f2 f2 f2 f2 00 00 00 f2
 ffff880038effa00: f2 f2 f2 f2 00 00 00 00 f2 f2 f2 f2 00 00 00 00
>ffff880038effa80: 00 00 f2 f2 f2 f2 f2 f2 00 00 00 00 00 00 00 f2
                                                                ^
 ffff880038effb00: f2 f2 f2 f2 00 00 00 00 00 00 00 00 00 f2 f2 f2
 ffff880038effb80: f3 f3 f3 f3 00 00 00 00 00 00 00 00 00 00 f1 f1
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