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BUG: KASAN: stack-out-of-bounds in __xfrm6_daddr_saddr_hash net/xfrm/xfrm_hash.h:28 [inline]
BUG: KASAN: stack-out-of-bounds in __xfrm_dst_hash net/xfrm/xfrm_hash.h:95 [inline]
BUG: KASAN: stack-out-of-bounds in xfrm_dst_hash net/xfrm/xfrm_state.c:46 [inline]
BUG: KASAN: stack-out-of-bounds in xfrm_state_find+0x2418/0x24e0 net/xfrm/xfrm_state.c:783
Read of size 4 at addr ffff8801d4b37660 by task syz-executor095/2079

CPU: 1 PID: 2079 Comm: syz-executor095 Not tainted 4.4.166+ #5
 0000000000000000 7c992b1a7f2ef3f8 ffff8801d4b36ce0 ffffffff81aa62ad
 ffffea000752cdc0 ffff8801d4b37660 0000000000000000 ffff8801d4b37660
 0000000000000003 ffff8801d4b36d18 ffffffff8148b12b ffff8801d4b37660
Call Trace:
 [<ffffffff81aa62ad>] __dump_stack lib/dump_stack.c:15 [inline]
 [<ffffffff81aa62ad>] dump_stack+0xc1/0x124 lib/dump_stack.c:51
 [<ffffffff8148b12b>] print_address_description+0x6c/0x217 mm/kasan/report.c:252
 [<ffffffff8148b44b>] kasan_report_error mm/kasan/report.c:351 [inline]
 [<ffffffff8148b44b>] kasan_report.cold.6+0x175/0x2f7 mm/kasan/report.c:408
 [<ffffffff81480154>] __asan_report_load4_noabort+0x14/0x20 mm/kasan/report.c:428
 [<ffffffff82562ce8>] __xfrm6_daddr_saddr_hash net/xfrm/xfrm_hash.h:28 [inline]
 [<ffffffff82562ce8>] __xfrm_dst_hash net/xfrm/xfrm_hash.h:95 [inline]
 [<ffffffff82562ce8>] xfrm_dst_hash net/xfrm/xfrm_state.c:46 [inline]
 [<ffffffff82562ce8>] xfrm_state_find+0x2418/0x24e0 net/xfrm/xfrm_state.c:783
 [<ffffffff825496c2>] xfrm_tmpl_resolve_one+0x1d2/0x7a0 net/xfrm/xfrm_policy.c:1455
 [<ffffffff82549ea9>] xfrm_tmpl_resolve net/xfrm/xfrm_policy.c:1499 [inline]
 [<ffffffff82549ea9>] xfrm_resolve_and_create_bundle+0x219/0x1da0 net/xfrm/xfrm_policy.c:1847
 [<ffffffff8254ce08>] xfrm_lookup+0x238/0xb70 net/xfrm/xfrm_policy.c:2204
 [<ffffffff8254e5e9>] xfrm_lookup_route+0x39/0x140 net/xfrm/xfrm_policy.c:2326
 [<ffffffff823a1cf0>] ip_route_output_flow+0x90/0xa0 net/ipv4/route.c:2437
 [<ffffffff8247b760>] udp_sendmsg+0x1480/0x1c70 net/ipv4/udp.c:1040
 [<ffffffff8260f5ad>] udpv6_sendmsg+0x12cd/0x24c0 net/ipv6/udp.c:1173
 [<ffffffff824a4c43>] inet_sendmsg+0x203/0x4d0 net/ipv4/af_inet.c:755
 [<ffffffff821d1d9b>] sock_sendmsg_nosec net/socket.c:638 [inline]
 [<ffffffff821d1d9b>] sock_sendmsg+0xbb/0x110 net/socket.c:648
 [<ffffffff821d38e1>] ___sys_sendmsg+0x441/0x880 net/socket.c:1975
 [<ffffffff821d6e6e>] __sys_sendmmsg+0x12e/0x2e0 net/socket.c:2060
 [<ffffffff821d7055>] SYSC_sendmmsg net/socket.c:2090 [inline]
 [<ffffffff821d7055>] SyS_sendmmsg+0x35/0x60 net/socket.c:2085
 [<ffffffff82715ce1>] entry_SYSCALL_64_fastpath+0x1e/0x9a

The buggy address belongs to the page:
page:ffffea000752cdc0 count:0 mapcount:0 mapping:          (null) index:0x0
flags: 0x4000000000000000()
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff8801d4b37500: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff8801d4b37580: 00 f1 f1 f1 f1 00 f2 f2 f2 f2 f2 f2 f2 00 00 00
>ffff8801d4b37600: f2 f2 f2 f2 f2 00 00 00 00 00 00 00 f2 f2 f2 f2
                                                       ^
 ffff8801d4b37680: f2 00 00 00 00 00 00 00 00 00 f2 f2 f2 00 00 00
 ffff8801d4b37700: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
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