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BUG: KASAN: stack-out-of-bounds in xfrm_state_find+0x2453/0x2830 net/xfrm/xfrm_state.c:822
Read of size 4 at addr ffff8801b0a17730 by task syzkaller142215/3803

CPU: 0 PID: 3803 Comm: syzkaller142215 Not tainted 4.9.84-ge7f51a5 #45
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
 ffff8801b0a16d80 ffffffff81d956b9 ffffea0006c285c0 ffff8801b0a17730
 0000000000000000 ffff8801b0a17730 ffff8801bbeb78a0 ffff8801b0a16db8
 ffffffff8153e1a3 ffff8801b0a17730 0000000000000004 0000000000000000
Call Trace:
 [<ffffffff81d956b9>] __dump_stack lib/dump_stack.c:15 [inline]
 [<ffffffff81d956b9>] dump_stack+0xc1/0x128 lib/dump_stack.c:51
 [<ffffffff8153e1a3>] print_address_description+0x73/0x280 mm/kasan/report.c:252
 [<ffffffff8153e6c5>] kasan_report_error mm/kasan/report.c:351 [inline]
 [<ffffffff8153e6c5>] kasan_report+0x275/0x360 mm/kasan/report.c:408
 [<ffffffff8153e804>] __asan_report_load4_noabort+0x14/0x20 mm/kasan/report.c:428
 [<ffffffff833dc0a3>] xfrm_state_find+0x2453/0x2830 net/xfrm/xfrm_state.c:822
 [<ffffffff833c12e8>] xfrm_tmpl_resolve_one net/xfrm/xfrm_policy.c:1483 [inline]
 [<ffffffff833c12e8>] xfrm_tmpl_resolve+0x298/0xa90 net/xfrm/xfrm_policy.c:1527
 [<ffffffff833c1bb7>] xfrm_resolve_and_create_bundle+0xd7/0x1d90 net/xfrm/xfrm_policy.c:1875
 [<ffffffff833c74c4>] xfrm_lookup+0x984/0xbf0 net/xfrm/xfrm_policy.c:2229
 [<ffffffff833c8629>] xfrm_lookup_route+0x39/0x1a0 net/xfrm/xfrm_policy.c:2351
 [<ffffffff831e184f>] ip_route_output_flow+0x7f/0xa0 net/ipv4/route.c:2435
 [<ffffffff832bf1f6>] udp_sendmsg+0xe36/0x1c10 net/ipv4/udp.c:1023
 [<ffffffff83490768>] udpv6_sendmsg+0x588/0x2540 net/ipv6/udp.c:1086
 [<ffffffff832f29ec>] inet_sendmsg+0x2bc/0x4c0 net/ipv4/af_inet.c:770
 [<ffffffff82ed8baa>] sock_sendmsg_nosec net/socket.c:635 [inline]
 [<ffffffff82ed8baa>] sock_sendmsg+0xca/0x110 net/socket.c:645
 [<ffffffff82eda7c1>] ___sys_sendmsg+0x6d1/0x7e0 net/socket.c:1969
 [<ffffffff82edc7f6>] __sys_sendmsg+0xd6/0x190 net/socket.c:2003
 [<ffffffff82edc8dd>] SYSC_sendmsg net/socket.c:2014 [inline]
 [<ffffffff82edc8dd>] SyS_sendmsg+0x2d/0x50 net/socket.c:2010
 [<ffffffff81006504>] do_syscall_64+0x1a4/0x490 arch/x86/entry/common.c:282
 [<ffffffff838b53fd>] entry_SYSCALL_64_after_swapgs+0x47/0xc5

The buggy address belongs to the page:
page:ffffea0006c285c0 count:0 mapcount:0 mapping:          (null) index:0x0
flags: 0x8000000000000000()
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff8801b0a17600: 00 00 00 00 00 00 00 00 00 00 00 f1 f1 f1 f1 00
 ffff8801b0a17680: f2 f2 f2 f2 f2 f2 f2 00 00 00 00 f2 f2 f2 f2 00
>ffff8801b0a17700: 00 00 00 00 00 00 f2 f2 f2 f2 f2 00 00 00 00 00
                                     ^
 ffff8801b0a17780: 00 00 00 00 f2 f2 f2 00 00 00 00 00 00 00 00 00
 ffff8801b0a17800: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
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