IPVS: set_ctl: invalid protocol: 4 127.0.0.1:20002 fo
IPVS: set_ctl: invalid protocol: 4 127.0.0.1:20002 fo
IPVS: set_ctl: invalid protocol: 135 172.20.20.187:20000 rr
==================================================================
BUG: KASAN: stack-out-of-bounds in strnlen+0xc1/0xd0 lib/string.c:498
Read of size 1 at addr ffff8801d2247c84 by task syz-executor5/11747

CPU: 0 PID: 11747 Comm: syz-executor5 Not tainted 4.4.133-g3f51ea2 #51
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
 0000000000000000 5fb72adb6609a933 ffff8801d22476f0 ffffffff81e0e4cd
 ffffea00074891c0 ffff8801d2247c84 0000000000000000 ffff8801d2247c84
 ffff8801d2247c50 ffff8801d2247728 ffffffff815154cc ffff8801d2247c84
Call Trace:
 [<ffffffff81e0e4cd>] __dump_stack lib/dump_stack.c:15 [inline]
 [<ffffffff81e0e4cd>] dump_stack+0xc1/0x124 lib/dump_stack.c:51
 [<ffffffff815154cc>] print_address_description+0x6c/0x216 mm/kasan/report.c:252
 [<ffffffff815157eb>] kasan_report_error mm/kasan/report.c:351 [inline]
 [<ffffffff815157eb>] kasan_report.cold.7+0x175/0x2f7 mm/kasan/report.c:408
 [<ffffffff814f9284>] __asan_report_load1_noabort+0x14/0x20 mm/kasan/report.c:426
 [<ffffffff81e29fd1>] strnlen+0xc1/0xd0 lib/string.c:498
 [<ffffffff81e320bc>] string.isra.4+0x4c/0x250 lib/vsprintf.c:518
 [<ffffffff81e37272>] vsnprintf+0x402/0x18e0 lib/vsprintf.c:1907
 [<ffffffff81e3877d>] vscnprintf+0x2d/0x60 lib/vsprintf.c:2010
 [<ffffffff8125cf6f>] vprintk_emit+0xdf/0x840 kernel/printk/printk.c:1729
 [<ffffffff8125d6f8>] vprintk+0x28/0x30 kernel/printk/printk.c:1843
 [<ffffffff8125d71d>] vprintk_default+0x1d/0x30 kernel/printk/printk.c:1844
 [<ffffffff814150d8>] printk+0xaf/0xd7 kernel/printk/printk.c:1922
 [<ffffffff8389caa4>] do_ip_vs_set_ctl.cold.37+0x32/0x37 net/netfilter/ipvs/ip_vs_ctl.c:2394
 [<ffffffff830c5b0d>] nf_sockopt net/netfilter/nf_sockopt.c:105 [inline]
 [<ffffffff830c5b0d>] nf_setsockopt+0x6d/0xc0 net/netfilter/nf_sockopt.c:114
 [<ffffffff8322534a>] ip_setsockopt+0x9a/0xb0 net/ipv4/ip_sockglue.c:1227
 [<ffffffff832ca6fa>] udp_setsockopt+0x4a/0x90 net/ipv4/udp.c:2162
 [<ffffffff8348228a>] ipv6_setsockopt+0x10a/0x130 net/ipv6/ipv6_sockglue.c:899
 [<ffffffff83242e68>] tcp_setsockopt+0x88/0xe0 net/ipv4/tcp.c:2643
 [<ffffffff82f237da>] sock_common_setsockopt+0x9a/0xe0 net/core/sock.c:2659
 [<ffffffff82f206f6>] SYSC_setsockopt net/socket.c:1767 [inline]
 [<ffffffff82f206f6>] SyS_setsockopt+0x166/0x260 net/socket.c:1746
 [<ffffffff838c0f65>] entry_SYSCALL_64_fastpath+0x22/0x9e

The buggy address belongs to the page:
page:ffffea00074891c0 count:0 mapcount:0 mapping:          (null) index:0x0
flags: 0x8000000000000000()
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff8801d2247b80: 00 00 00 00 00 04 f2 f2 f2 f2 f2 f2 00 00 00 00
 ffff8801d2247c00: 00 00 00 00 f2 f2 f2 f2 00 00 00 00 00 00 00 00
>ffff8801d2247c80: 04 f2 f2 f2 00 00 00 00 00 00 00 00 00 00 00 00
                   ^
 ffff8801d2247d00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff8801d2247d80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
==================================================================