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BUG: KASAN: stack-out-of-bounds in xfrm_state_find+0x30de/0x3210 net/xfrm/xfrm_state.c:1051
Read of size 4 at addr ffff8801aa5575f0 by task syz-executor3/17605

CPU: 0 PID: 17605 Comm: syz-executor3 Not tainted 4.16.0-rc4+ #258
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_load4_noabort+0x14/0x20 mm/kasan/report.c:432
 xfrm_state_find+0x30de/0x3210 net/xfrm/xfrm_state.c:1051
 xfrm_tmpl_resolve_one net/xfrm/xfrm_policy.c:1393 [inline]
 xfrm_tmpl_resolve+0x2ee/0xc40 net/xfrm/xfrm_policy.c:1437
 xfrm_resolve_and_create_bundle+0x184/0x28d0 net/xfrm/xfrm_policy.c:1830
 xfrm_lookup+0xfcb/0x25c0 net/xfrm/xfrm_policy.c:2160
 xfrm_lookup_route+0x39/0x1a0 net/xfrm/xfrm_policy.c:2280
 ip_route_output_flow+0x7c/0xa0 net/ipv4/route.c:2560
 udp_sendmsg+0x19bd/0x2f70 net/ipv4/udp.c:1012
 udpv6_sendmsg+0x757/0x3400 net/ipv6/udp.c:1156
 inet_sendmsg+0x11f/0x5e0 net/ipv4/af_inet.c:763
 sock_sendmsg_nosec net/socket.c:629 [inline]
 sock_sendmsg+0xca/0x110 net/socket.c:639
 SYSC_sendto+0x361/0x5c0 net/socket.c:1748
 SyS_sendto+0x40/0x50 net/socket.c:1716
 do_syscall_64+0x281/0x940 arch/x86/entry/common.c:287
 entry_SYSCALL_64_after_hwframe+0x42/0xb7
RIP: 0033:0x453e69
RSP: 002b:00007f9343777c68 EFLAGS: 00000246 ORIG_RAX: 000000000000002c
RAX: ffffffffffffffda RBX: 00007f93437786d4 RCX: 0000000000453e69
RDX: 000000000000003b RSI: 0000000020000040 RDI: 0000000000000013
RBP: 000000000072bea0 R08: 0000000020000100 R09: 000000000000001c
R10: 0000000000000004 R11: 0000000000000246 R12: 00000000ffffffff
R13: 00000000000004cd R14: 00000000006f73d8 R15: 0000000000000000

The buggy address belongs to the page:
page:ffffea0006a955c0 count:0 mapcount:0 mapping:0000000000000000 index:0x0
flags: 0x2fffc0000000000()
raw: 02fffc0000000000 0000000000000000 0000000000000000 00000000ffffffff
raw: 0000000000000000 ffffea0006a90101 0000000000000000 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff8801aa557480: 00 00 00 f1 f1 f1 f1 04 f2 f2 f2 f2 f2 f2 f2 00
 ffff8801aa557500: f2 f2 f2 f2 f2 f2 f2 f8 f2 f2 f2 f2 f2 f2 f2 00
>ffff8801aa557580: 00 00 00 f2 f2 f2 f2 00 00 00 00 00 00 00 f2 f2
                                                             ^
 ffff8801aa557600: f2 f2 f2 00 00 00 00 00 00 00 00 00 f2 f2 f2 00
 ffff8801aa557680: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
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