netlink: 3 bytes leftover after parsing attributes in process `syz-executor0'.
netlink: 3 bytes leftover after parsing attributes in process `syz-executor0'.
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BUG: KASAN: stack-out-of-bounds in strnlen+0xc1/0xd0 lib/string.c:498
Read of size 1 at addr ffff8800adb7fc84 by task syz-executor1/6615

CPU: 0 PID: 6615 Comm: syz-executor1 Not tainted 4.4.132-g1a2b3e7 #45
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
 0000000000000000 b53405111e5d7d9d ffff8800adb7f6f0 ffffffff81e0df8d
 ffffea0002b6dfc0 ffff8800adb7fc84 0000000000000000 ffff8800adb7fc84
 ffff8800adb7fc50 ffff8800adb7f728 ffffffff8151526c ffff8800adb7fc84
Call Trace:
 [<ffffffff81e0df8d>] __dump_stack lib/dump_stack.c:15 [inline]
 [<ffffffff81e0df8d>] dump_stack+0xc1/0x124 lib/dump_stack.c:51
 [<ffffffff8151526c>] print_address_description+0x6c/0x216 mm/kasan/report.c:252
 [<ffffffff8151558b>] kasan_report_error mm/kasan/report.c:351 [inline]
 [<ffffffff8151558b>] kasan_report.cold.7+0x175/0x2f7 mm/kasan/report.c:408
 [<ffffffff814f9024>] __asan_report_load1_noabort+0x14/0x20 mm/kasan/report.c:426
 [<ffffffff81e29a91>] strnlen+0xc1/0xd0 lib/string.c:498
 [<ffffffff81e31b7c>] string.isra.4+0x4c/0x250 lib/vsprintf.c:518
 [<ffffffff81e36d32>] vsnprintf+0x402/0x18e0 lib/vsprintf.c:1907
 [<ffffffff81e3823d>] vscnprintf+0x2d/0x60 lib/vsprintf.c:2010
 [<ffffffff8125cebf>] vprintk_emit+0xdf/0x840 kernel/printk/printk.c:1729
 [<ffffffff8125d648>] vprintk+0x28/0x30 kernel/printk/printk.c:1843
 [<ffffffff8125d66d>] vprintk_default+0x1d/0x30 kernel/printk/printk.c:1844
 [<ffffffff81414f88>] printk+0xaf/0xd7 kernel/printk/printk.c:1922
 [<ffffffff8389bd84>] do_ip_vs_set_ctl.cold.37+0x32/0x37 net/netfilter/ipvs/ip_vs_ctl.c:2394
 [<ffffffff830c564d>] nf_sockopt net/netfilter/nf_sockopt.c:105 [inline]
 [<ffffffff830c564d>] nf_setsockopt+0x6d/0xc0 net/netfilter/nf_sockopt.c:114
 [<ffffffff83224d3a>] ip_setsockopt+0x9a/0xb0 net/ipv4/ip_sockglue.c:1227
 [<ffffffff832c9c7a>] udp_setsockopt+0x4a/0x90 net/ipv4/udp.c:2159
 [<ffffffff834815ca>] ipv6_setsockopt+0x10a/0x130 net/ipv6/ipv6_sockglue.c:899
 [<ffffffff83242858>] tcp_setsockopt+0x88/0xe0 net/ipv4/tcp.c:2643
 [<ffffffff82f2343a>] sock_common_setsockopt+0x9a/0xe0 net/core/sock.c:2659
 [<ffffffff82f20356>] SYSC_setsockopt net/socket.c:1767 [inline]
 [<ffffffff82f20356>] SyS_setsockopt+0x166/0x260 net/socket.c:1746
 [<ffffffff838c0225>] entry_SYSCALL_64_fastpath+0x22/0x9e

The buggy address belongs to the page:
page:ffffea0002b6dfc0 count:0 mapcount:0 mapping:          (null) index:0x0
flags: 0x4000000000000000()
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff8800adb7fb80: 00 00 00 00 00 04 f2 f2 f2 f2 f2 f2 00 00 00 00
 ffff8800adb7fc00: 00 00 00 00 f2 f2 f2 f2 00 00 00 00 00 00 00 00
>ffff8800adb7fc80: 04 f2 f2 f2 00 00 00 00 00 00 00 00 00 00 00 00
                   ^
 ffff8800adb7fd00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff8800adb7fd80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
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