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BUG: KASAN: stack-out-of-bounds in strlen lib/string.c:481 [inline]
BUG: KASAN: stack-out-of-bounds in strlcpy+0x101/0x120 lib/string.c:141
Read of size 1 at addr ffff8801a5d6fb8c by task syz-executor2/11895

CPU: 1 PID: 11895 Comm: syz-executor2 Not tainted 4.9.123-g520d10d3 #33
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
 ffff8801a5d6fa68 ffffffff81eb9689 ffffea0006975bc0 ffff8801a5d6fb8c
 0000000000000000 ffff8801a5d6fb8c 0000000000000040 ffff8801a5d6faa0
 ffffffff8156c3fe ffff8801a5d6fb8c 0000000000000001 0000000000000000
Call Trace:
 [<ffffffff81eb9689>] __dump_stack lib/dump_stack.c:15 [inline]
 [<ffffffff81eb9689>] dump_stack+0xc1/0x128 lib/dump_stack.c:51
 [<ffffffff8156c3fe>] print_address_description+0x6c/0x234 mm/kasan/report.c:256
 [<ffffffff8156c808>] kasan_report_error mm/kasan/report.c:355 [inline]
 [<ffffffff8156c808>] kasan_report.cold.6+0x242/0x2fe mm/kasan/report.c:412
 [<ffffffff8153fb34>] __asan_report_load1_noabort+0x14/0x20 mm/kasan/report.c:430
 [<ffffffff81ed8111>] strlen lib/string.c:481 [inline]
 [<ffffffff81ed8111>] strlcpy+0x101/0x120 lib/string.c:141
 [<ffffffff83281d02>] xt_copy_counters_from_user+0x152/0x300 net/netfilter/x_tables.c:880
 [<ffffffff83665f46>] do_add_counters+0x96/0x5c0 net/ipv6/netfilter/ip6_tables.c:1217
 [<ffffffff83666546>] compat_do_ip6t_set_ctl+0xd6/0x140 net/ipv6/netfilter/ip6_tables.c:1592
 [<ffffffff831e62ab>] compat_nf_sockopt net/netfilter/nf_sockopt.c:143 [inline]
 [<ffffffff831e62ab>] compat_nf_setsockopt+0x8b/0x130 net/netfilter/nf_sockopt.c:155
 [<ffffffff835bcb8d>] compat_ipv6_setsockopt+0x15d/0x1d0 net/ipv6/ipv6_sockglue.c:942
 [<ffffffff835cc39a>] compat_udpv6_setsockopt+0x4a/0x90 net/ipv6/udp.c:1361
 [<ffffffff830249b4>] compat_sock_common_setsockopt+0xb4/0x150 net/core/sock.c:2717
 [<ffffffff8312335c>] C_SYSC_setsockopt net/compat.c:399 [inline]
 [<ffffffff8312335c>] compat_SyS_setsockopt+0x14c/0x2a0 net/compat.c:382
 [<ffffffff81006da7>] do_syscall_32_irqs_on arch/x86/entry/common.c:325 [inline]
 [<ffffffff81006da7>] do_fast_syscall_32+0x2f7/0x870 arch/x86/entry/common.c:387
 [<ffffffff83a03490>] entry_SYSENTER_compat+0x90/0xa2 arch/x86/entry/entry_64_compat.S:137

The buggy address belongs to the page:
page:ffffea0006975bc0 count:0 mapcount:0 mapping:          (null) index:0x0
flags: 0x8000000000000000()
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff8801a5d6fa80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff8801a5d6fb00: 00 00 00 00 00 00 00 00 00 f1 f1 f1 f1 00 00 00
>ffff8801a5d6fb80: 00 04 f2 f2 f2 00 00 00 00 00 00 00 00 00 00 00
                      ^
 ffff8801a5d6fc00: 00 00 00 00 00 00 00 00 00 00 f1 f1 f1 f1 00 00
 ffff8801a5d6fc80: 00 00 00 f2 f2 f2 00 00 00 00 00 00 00 00 00 00
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