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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 ffff8800a439fafc by task syz-executor4/20169

CPU: 0 PID: 20169 Comm: syz-executor4 Not tainted 4.4.155+ #34
 0000000000000000 d21dda08070fee5e ffff8800a439f9d8 ffffffff81a556dd
 ffffea000290e7c0 ffff8800a439fafc 0000000000000000 ffff8800a439fafc
 ffff8800a439fbe0 ffff8800a439fa10 ffffffff8146c8f9 ffff8800a439fafc
Call Trace:
 [<ffffffff81a556dd>] __dump_stack lib/dump_stack.c:15 [inline]
 [<ffffffff81a556dd>] dump_stack+0xc1/0x124 lib/dump_stack.c:51
 [<ffffffff8146c8f9>] print_address_description+0x6c/0x217 mm/kasan/report.c:252
 [<ffffffff8146cc19>] kasan_report_error mm/kasan/report.c:351 [inline]
 [<ffffffff8146cc19>] kasan_report.cold.6+0x175/0x2f7 mm/kasan/report.c:408
 [<ffffffff81461ac4>] __asan_report_load1_noabort+0x14/0x20 mm/kasan/report.c:426
 [<ffffffff81a71981>] strlen lib/string.c:481 [inline]
 [<ffffffff81a71981>] strlcpy+0x101/0x120 lib/string.c:141
 [<ffffffff822ec03e>] xt_copy_counters_from_user+0x13e/0x2e0 net/netfilter/x_tables.c:879
 [<ffffffff82603156>] do_add_counters+0x96/0x5c0 net/ipv6/netfilter/ip6_tables.c:1343
 [<ffffffff82608a36>] compat_do_ip6t_set_ctl+0xd6/0x140 net/ipv6/netfilter/ip6_tables.c:1736
 [<ffffffff8227b9cb>] compat_nf_sockopt net/netfilter/nf_sockopt.c:143 [inline]
 [<ffffffff8227b9cb>] compat_nf_setsockopt+0x8b/0x130 net/netfilter/nf_sockopt.c:155
 [<ffffffff82579fad>] compat_ipv6_setsockopt+0x15d/0x1d0 net/ipv6/ipv6_sockglue.c:940
 [<ffffffff823607b7>] inet_csk_compat_setsockopt+0x97/0x120 net/ipv4/inet_connection_sock.c:914
 [<ffffffff823746fd>] compat_tcp_setsockopt+0x3d/0x70 net/ipv4/tcp.c:2654
 [<ffffffff82161d64>] compat_sock_common_setsockopt+0xb4/0x150 net/core/sock.c:2670
 [<ffffffff8222c699>] C_SYSC_setsockopt net/compat.c:385 [inline]
 [<ffffffff8222c699>] compat_SyS_setsockopt+0x169/0x6e0 net/compat.c:368
 [<ffffffff81005ffe>] do_syscall_32_irqs_on arch/x86/entry/common.c:393 [inline]
 [<ffffffff81005ffe>] do_fast_syscall_32+0x31e/0x8b0 arch/x86/entry/common.c:460
 [<ffffffff82692350>] sysenter_flags_fixed+0xd/0x1a

The buggy address belongs to the page:
page:ffffea000290e7c0 count:0 mapcount:0 mapping:          (null) index:0x0
flags: 0x0()
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff8800a439f980: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff8800a439fa00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
>ffff8800a439fa80: 00 00 00 00 00 00 00 f1 f1 f1 f1 00 00 00 00 04
                                                                ^
 ffff8800a439fb00: f2 f2 f2 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff8800a439fb80: 00 00 00 00 00 00 00 00 f1 f1 f1 f1 00 00 00 00
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