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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:60 [inline]
BUG: KASAN: stack-out-of-bounds in xfrm_state_find+0x269d/0x2920 net/xfrm/xfrm_state.c:807
Read of size 4 at addr ffff88019f9a7650 by task syz-executor0/7670

CPU: 0 PID: 7670 Comm: syz-executor0 Not tainted 4.9.147+ #86
 ffff88019f9a6cc0 ffffffff81b43be9 ffffea00067e69c0 ffff88019f9a7650
 0000000000000000 ffff88019f9a7650 ffff8801cb487870 ffff88019f9a6cf8
 ffffffff81500cd8 ffff88019f9a7650 0000000000000004 0000000000000000
Call Trace:
 [<ffffffff81b43be9>] __dump_stack lib/dump_stack.c:15 [inline]
 [<ffffffff81b43be9>] dump_stack+0xc1/0x128 lib/dump_stack.c:51
 [<ffffffff81500cd8>] print_address_description+0x6c/0x234 mm/kasan/report.c:256
 [<ffffffff815010e2>] kasan_report_error mm/kasan/report.c:355 [inline]
 [<ffffffff815010e2>] kasan_report.cold.6+0x242/0x2fe mm/kasan/report.c:412
 [<ffffffff814f3374>] __asan_report_load4_noabort+0x14/0x20 mm/kasan/report.c:432
 [<ffffffff8265978d>] __xfrm6_daddr_saddr_hash net/xfrm/xfrm_hash.h:28 [inline]
 [<ffffffff8265978d>] __xfrm_dst_hash net/xfrm/xfrm_hash.h:95 [inline]
 [<ffffffff8265978d>] xfrm_dst_hash net/xfrm/xfrm_state.c:60 [inline]
 [<ffffffff8265978d>] xfrm_state_find+0x269d/0x2920 net/xfrm/xfrm_state.c:807
 [<ffffffff8263f122>] xfrm_tmpl_resolve_one+0x1d2/0x7a0 net/xfrm/xfrm_policy.c:1500
 [<ffffffff8263f90f>] xfrm_tmpl_resolve net/xfrm/xfrm_policy.c:1544 [inline]
 [<ffffffff8263f90f>] xfrm_resolve_and_create_bundle+0x21f/0x1e70 net/xfrm/xfrm_policy.c:1893
 [<ffffffff82642a09>] xfrm_lookup+0x239/0xc00 net/xfrm/xfrm_policy.c:2254
 [<ffffffff82644269>] xfrm_lookup_route+0x39/0x140 net/xfrm/xfrm_policy.c:2379
 [<ffffffff8248e730>] ip_route_output_flow+0x90/0xa0 net/ipv4/route.c:2448
 [<ffffffff8256e309>] udp_sendmsg+0x13d9/0x1c60 net/ipv4/udp.c:1025
 [<ffffffff8270adad>] udpv6_sendmsg+0x127d/0x2430 net/ipv6/udp.c:1086
 [<ffffffff82597793>] inet_sendmsg+0x203/0x4d0 net/ipv4/af_inet.c:770
 [<ffffffff822a281b>] sock_sendmsg_nosec net/socket.c:648 [inline]
 [<ffffffff822a281b>] sock_sendmsg+0xbb/0x110 net/socket.c:658
 [<ffffffff822a427a>] ___sys_sendmsg+0x47a/0x840 net/socket.c:1982
 [<ffffffff822a7781>] __sys_sendmmsg+0x161/0x3d0 net/socket.c:2072
 [<ffffffff822a7a25>] SYSC_sendmmsg net/socket.c:2103 [inline]
 [<ffffffff822a7a25>] SyS_sendmmsg+0x35/0x60 net/socket.c:2098
 [<ffffffff810056ef>] do_syscall_64+0x19f/0x550 arch/x86/entry/common.c:285
 [<ffffffff8281a4d3>] entry_SYSCALL_64_after_swapgs+0x5d/0xdb

The buggy address belongs to the page:
page:ffffea00067e69c0 count:0 mapcount:0 mapping:          (null) index:0x0
flags: 0x4000000000000000()
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff88019f9a7500: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 f1
 ffff88019f9a7580: f1 f1 f1 00 f2 f2 f2 f2 f2 f2 f2 00 00 00 00 f2
>ffff88019f9a7600: f2 f2 f2 00 00 00 00 00 00 00 f2 f2 f2 f2 f2 00
                                                 ^
 ffff88019f9a7680: 00 00 00 00 00 00 00 00 f2 f2 f2 00 00 00 00 00
 ffff88019f9a7700: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
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