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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 ffff8801a5407b8c by task syz-executor7/6131

CPU: 1 PID: 6131 Comm: syz-executor7 Not tainted 4.9.121-g681e57b #29
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
sg_write: data in/out 7067820/529 bytes for SCSI command 0x0-- guessing data in;
   program syz-executor4 not setting count and/or reply_len properly
 ffff8801a5407a68 ffffffff81eb7e29 ffffea00069501c0 ffff8801a5407b8c
 0000000000000000 ffff8801a5407b8c 0000000000000040 ffff8801a5407aa0
 ffffffff8156acee ffff8801a5407b8c 0000000000000001 0000000000000000
Call Trace:
 [<ffffffff81eb7e29>] __dump_stack lib/dump_stack.c:15 [inline]
 [<ffffffff81eb7e29>] dump_stack+0xc1/0x128 lib/dump_stack.c:51
 [<ffffffff8156acee>] print_address_description+0x6c/0x234 mm/kasan/report.c:256
 [<ffffffff8156b0f8>] kasan_report_error mm/kasan/report.c:355 [inline]
 [<ffffffff8156b0f8>] kasan_report.cold.6+0x242/0x2fe mm/kasan/report.c:412
 [<ffffffff8153e9d4>] __asan_report_load1_noabort+0x14/0x20 mm/kasan/report.c:430
 [<ffffffff81ed6881>] strlen lib/string.c:481 [inline]
 [<ffffffff81ed6881>] strlcpy+0x101/0x120 lib/string.c:141
 [<ffffffff8327fbe2>] xt_copy_counters_from_user+0x152/0x300 net/netfilter/x_tables.c:880
 [<ffffffff83663e26>] do_add_counters+0x96/0x5c0 net/ipv6/netfilter/ip6_tables.c:1217
 [<ffffffff83664426>] compat_do_ip6t_set_ctl+0xd6/0x140 net/ipv6/netfilter/ip6_tables.c:1592
 [<ffffffff831e418b>] compat_nf_sockopt net/netfilter/nf_sockopt.c:143 [inline]
 [<ffffffff831e418b>] compat_nf_setsockopt+0x8b/0x130 net/netfilter/nf_sockopt.c:155
 [<ffffffff835baa6d>] compat_ipv6_setsockopt+0x15d/0x1d0 net/ipv6/ipv6_sockglue.c:942
 [<ffffffff835ca27a>] compat_udpv6_setsockopt+0x4a/0x90 net/ipv6/udp.c:1361
 [<ffffffff830228b4>] compat_sock_common_setsockopt+0xb4/0x150 net/core/sock.c:2717
 [<ffffffff8312125c>] C_SYSC_setsockopt net/compat.c:399 [inline]
 [<ffffffff8312125c>] 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
 [<ffffffff83a013d0>] entry_SYSENTER_compat+0x90/0xa2 arch/x86/entry/entry_64_compat.S:137

The buggy address belongs to the page:
page:ffffea00069501c0 count:0 mapcount:0 mapping:          (null) index:0x0
flags: 0x8000000000000000()
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff8801a5407a80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff8801a5407b00: 00 00 00 00 00 00 00 00 00 f1 f1 f1 f1 00 00 00
>ffff8801a5407b80: 00 04 f2 f2 f2 00 00 00 00 00 00 00 00 00 00 00
                      ^
 ffff8801a5407c00: 00 00 00 00 00 00 00 00 00 00 f1 f1 f1 f1 00 00
 ffff8801a5407c80: 00 00 00 f2 f2 f2 00 00 00 00 00 00 00 00 00 00
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