================================================================== BUG: KASAN: stack-out-of-bounds in strnlen+0xc1/0xd0 lib/string.c:498 Read of size 1 at addr ffff8801cf027c84 by task syz-executor0/16978 CPU: 1 PID: 16978 Comm: syz-executor0 Not tainted 4.4.138-gcf21a9a #64 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 0000000000000000 b0974ced3378d7db ffff8801cf0276f0 ffffffff81e0ed0d ffffea00073c09c0 ffff8801cf027c84 0000000000000000 ffff8801cf027c84 ffff8801cf027c50 ffff8801cf027728 ffffffff81515a16 ffff8801cf027c84 Call Trace: [] __dump_stack lib/dump_stack.c:15 [inline] [] dump_stack+0xc1/0x124 lib/dump_stack.c:51 [] print_address_description+0x6c/0x216 mm/kasan/report.c:252 [] kasan_report_error mm/kasan/report.c:351 [inline] [] kasan_report.cold.7+0x175/0x2f7 mm/kasan/report.c:408 [] __asan_report_load1_noabort+0x14/0x20 mm/kasan/report.c:426 [] strnlen+0xc1/0xd0 lib/string.c:498 [] string.isra.4+0x4c/0x250 lib/vsprintf.c:518 [] vsnprintf+0x402/0x18e0 lib/vsprintf.c:1907 [] vscnprintf+0x2d/0x60 lib/vsprintf.c:2010 [] vprintk_emit+0xdf/0x840 kernel/printk/printk.c:1729 [] vprintk+0x28/0x30 kernel/printk/printk.c:1843 [] vprintk_default+0x1d/0x30 kernel/printk/printk.c:1844 [] printk+0xaf/0xd7 kernel/printk/printk.c:1922 [] do_ip_vs_set_ctl.cold.37+0x32/0x37 net/netfilter/ipvs/ip_vs_ctl.c:2394 [] nf_sockopt net/netfilter/nf_sockopt.c:105 [inline] [] nf_setsockopt+0x6d/0xc0 net/netfilter/nf_sockopt.c:114 [] ip_setsockopt+0x9a/0xb0 net/ipv4/ip_sockglue.c:1225 [] udp_setsockopt+0x4a/0x90 net/ipv4/udp.c:2162 [] ipv6_setsockopt+0x10a/0x130 net/ipv6/ipv6_sockglue.c:899 [] tcp_setsockopt+0x88/0xe0 net/ipv4/tcp.c:2643 [] sock_common_setsockopt+0x9a/0xe0 net/core/sock.c:2659 [] SYSC_setsockopt net/socket.c:1767 [inline] [] SyS_setsockopt+0x166/0x260 net/socket.c:1746 [] entry_SYSCALL_64_fastpath+0x22/0x9e The buggy address belongs to the page: page:ffffea00073c09c0 count:0 mapcount:0 mapping: (null) index:0x0 flags: 0x8000000000000000() page dumped because: kasan: bad access detected Memory state around the buggy address: ffff8801cf027b80: 00 00 00 00 00 04 f2 f2 f2 f2 f2 f2 00 00 00 00 ffff8801cf027c00: 00 00 00 00 f2 f2 f2 f2 00 00 00 00 00 00 00 00 >ffff8801cf027c80: 04 f2 f2 f2 00 00 00 00 00 00 00 00 00 00 00 00 ^ ffff8801cf027d00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff8801cf027d80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ==================================================================