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BUG: KASAN: stack-out-of-bounds in xfrm_state_find+0x30de/0x3210 net/xfrm/xfrm_state.c:1050
Read of size 4 at addr ffff8801c592f430 by task syz-executor1/28358

CPU: 1 PID: 28358 Comm: syz-executor1 Not tainted 4.15.0-rc7+ #168
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+0x194/0x257 lib/dump_stack.c:53
 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+0x30de/0x3210 net/xfrm/xfrm_state.c:1050
 xfrm_tmpl_resolve_one net/xfrm/xfrm_policy.c:1394 [inline]
 xfrm_tmpl_resolve+0x2ee/0xc40 net/xfrm/xfrm_policy.c:1438
 xfrm_resolve_and_create_bundle+0x172/0x2760 net/xfrm/xfrm_policy.c:1827
 xfrm_lookup+0x15bb/0x2500 net/xfrm/xfrm_policy.c:2153
 xfrm_lookup_route+0x39/0x1a0 net/xfrm/xfrm_policy.c:2271
 ip_route_output_flow+0x7c/0xa0 net/ipv4/route.c:2559
 udp_sendmsg+0x19d3/0x2cf0 net/ipv4/udp.c:1019
 udpv6_sendmsg+0x757/0x3400 net/ipv6/udp.c:1186
 inet_sendmsg+0x11f/0x5e0 net/ipv4/af_inet.c:763
 sock_sendmsg_nosec net/socket.c:638 [inline]
 sock_sendmsg+0xca/0x110 net/socket.c:648
 ___sys_sendmsg+0x767/0x8b0 net/socket.c:2028
 __sys_sendmsg+0xe5/0x210 net/socket.c:2062
 C_SYSC_sendmsg net/compat.c:739 [inline]
 compat_SyS_sendmsg+0x2a/0x40 net/compat.c:737
 do_syscall_32_irqs_on arch/x86/entry/common.c:327 [inline]
 do_fast_syscall_32+0x3ee/0xf9d arch/x86/entry/common.c:389
 entry_SYSENTER_compat+0x54/0x63 arch/x86/entry/entry_64_compat.S:129
RIP: 0023:0xf7fadc79
RSP: 002b:00000000f77a908c EFLAGS: 00000296 ORIG_RAX: 0000000000000172
RAX: ffffffffffffffda RBX: 0000000000000013 RCX: 00000000201f1000
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000

The buggy address belongs to the page:
page:ffffea0007164bc0 count:0 mapcount:0 mapping:          (null) index:0x0
flags: 0x2fffc0000000000()
raw: 02fffc0000000000 0000000000000000 0000000000000000 00000000ffffffff
raw: 0000000000000000 0000000100000001 0000000000000000 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff8801c592f300: f2 f2 f2 f2 f2 f2 f2 00 f2 f2 f2 f2 f2 f2 f2 f8
 ffff8801c592f380: f2 f2 f2 f2 f2 f2 f2 00 00 00 00 f2 f2 f2 f2 00
>ffff8801c592f400: 00 00 00 00 00 00 f2 f2 f2 f2 f2 00 00 00 00 00
                                     ^
 ffff8801c592f480: 00 00 00 00 f2 f2 f2 00 00 00 00 00 00 00 00 00
 ffff8801c592f500: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
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