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BUG: KASAN: stack-out-of-bounds in memcmp+0x126/0x160 lib/string.c:742
Read of size 1 at addr ffff8800ba45f860 by task syz-executor5/18066
ÿ: renamed from bcsh0

CPU: 0 PID: 18066 Comm: syz-executor5 Not tainted 4.4.125-g38f41ec #21
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
 0000000000000000 cdf43af5b1d073c6 ffff8800ba45f398 ffffffff81d067bd
 ffffea0002e917c0 ffff8800ba45f860 0000000000000000 ffff8800ba45f860
 ffff8800ba45f848 ffff8800ba45f3d0 ffffffff814fea83 ffff8800ba45f860
Call Trace:
 [<ffffffff81d067bd>] __dump_stack lib/dump_stack.c:15 [inline]
 [<ffffffff81d067bd>] dump_stack+0xc1/0x124 lib/dump_stack.c:51
 [<ffffffff814fea83>] print_address_description+0x73/0x260 mm/kasan/report.c:252
 [<ffffffff814fef95>] kasan_report_error mm/kasan/report.c:351 [inline]
 [<ffffffff814fef95>] kasan_report+0x285/0x370 mm/kasan/report.c:408
 [<ffffffff814ff094>] __asan_report_load1_noabort+0x14/0x20 mm/kasan/report.c:426
 [<ffffffff81d22bd6>] memcmp+0x126/0x160 lib/string.c:742
 [<ffffffff832ae477>] addr_match include/net/xfrm.h:837 [inline]
 [<ffffffff832ae477>] __xfrm6_selector_match net/xfrm/xfrm_policy.c:81 [inline]
 [<ffffffff832ae477>] xfrm_selector_match+0x1c7/0xe50 net/xfrm/xfrm_policy.c:95
 [<ffffffff832af253>] xfrm_sk_policy_lookup+0x153/0x360 net/xfrm/xfrm_policy.c:1236
 [<ffffffff832b1fee>] xfrm_lookup+0x1be/0xc10 net/xfrm/xfrm_policy.c:2184
 [<ffffffff832b3949>] xfrm_lookup_route+0x39/0x1a0 net/xfrm/xfrm_policy.c:2318
 [<ffffffff833084d4>] ip6_dst_lookup_flow+0x1b4/0x2e0 net/ipv6/ip6_output.c:1070
 [<ffffffff833ae37e>] tcp_v6_connect+0xade/0x1b90 net/ipv6/tcp_ipv6.c:249
 [<ffffffff831d6e26>] __inet_stream_connect+0x2a6/0xc70 net/ipv4/af_inet.c:615
 [<ffffffff83126e11>] tcp_sendmsg_fastopen net/ipv4/tcp.c:1092 [inline]
 [<ffffffff83126e11>] tcp_sendmsg+0xcc1/0x2b10 net/ipv4/tcp.c:1112
 [<ffffffff831dde2c>] inet_sendmsg+0x2bc/0x4c0 net/ipv4/af_inet.c:755
 [<ffffffff82df168a>] sock_sendmsg_nosec net/socket.c:625 [inline]
 [<ffffffff82df168a>] sock_sendmsg+0xca/0x110 net/socket.c:635
 [<ffffffff82df25d8>] SYSC_sendto+0x2c8/0x340 net/socket.c:1665
 [<ffffffff82df4ad0>] SyS_sendto+0x40/0x50 net/socket.c:1633
 [<ffffffff81006d91>] do_syscall_32_irqs_on arch/x86/entry/common.c:392 [inline]
 [<ffffffff81006d91>] do_fast_syscall_32+0x321/0x8a0 arch/x86/entry/common.c:459
 [<ffffffff8377b2aa>] sysenter_flags_fixed+0xd/0x17

The buggy address belongs to the page:
page:ffffea0002e917c0 count:0 mapcount:0 mapping:          (null) index:0x0
flags: 0x4000000000000000()
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff8800ba45f700: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff8800ba45f780: 00 00 00 00 00 00 f1 f1 f1 f1 00 00 f2 f2 f2 f2
>ffff8800ba45f800: f2 f2 00 00 00 00 00 00 00 00 00 00 f2 f2 00 00
                                                       ^
 ffff8800ba45f880: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff8800ba45f900: 00 00 00 00 f1 f1 f1 f1 00 00 00 00 00 f2 f2 f2
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