TCP: request_sock_TCP: Possible SYN flooding on port 20002. Sending cookies. Check SNMP counters. TCP: request_sock_TCPv6: Possible SYN flooding on port 20002. Sending cookies. Check SNMP counters. ================================================================== BUG: KASAN: stack-out-of-bounds in string+0x25b/0x2a0 lib/vsprintf.c:592 Read of size 1 at addr ffff8801b8947ca4 by task syz-executor1/7289 CPU: 1 PID: 7289 Comm: syz-executor1 Not tainted 4.9.107-gdb2c520 #49 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 ffff8801b89476b8 ffffffff81eb3da9 ffffea0006e251c0 ffff8801b8947ca4 0000000000000000 ffff8801b8947ca4 0000000000000034 ffff8801b89476f0 ffffffff815679f9 ffff8801b8947ca4 0000000000000001 0000000000000000 Call Trace: [] __dump_stack lib/dump_stack.c:15 [inline] [] dump_stack+0xc1/0x128 lib/dump_stack.c:51 [] print_address_description+0x6c/0x234 mm/kasan/report.c:256 [] kasan_report_error mm/kasan/report.c:355 [inline] [] kasan_report.cold.6+0x242/0x2fe mm/kasan/report.c:412 [] __asan_report_load1_noabort+0x14/0x20 mm/kasan/report.c:430 [] string+0x25b/0x2a0 lib/vsprintf.c:592 [] vsnprintf+0x406/0x1840 lib/vsprintf.c:2044 [] vscnprintf+0x2d/0x60 lib/vsprintf.c:2147 [] vprintk_emit+0xf4/0x790 kernel/printk/printk.c:1847 [] vprintk+0x28/0x30 kernel/printk/printk.c:1913 [] vprintk_default+0x1d/0x30 kernel/printk/printk.c:1914 [] vprintk_func kernel/printk/internal.h:36 [inline] [] printk+0xaf/0xd7 kernel/printk/printk.c:1975 [] do_ip_vs_set_ctl.cold.36+0x34/0x39 net/netfilter/ipvs/ip_vs_ctl.c:2435 [] 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:1249 [] udp_setsockopt+0x4a/0x90 net/ipv4/udp.c:2091 [] sock_common_setsockopt+0x9a/0xe0 net/core/sock.c:2706 [] SYSC_setsockopt net/socket.c:1772 [inline] [] SyS_setsockopt+0x166/0x260 net/socket.c:1751 [] do_syscall_64+0x1a6/0x490 arch/x86/entry/common.c:282 [] entry_SYSCALL_64_after_swapgs+0x5d/0xdb The buggy address belongs to the page: page:ffffea0006e251c0 count:0 mapcount:0 mapping: (null) index:0x0 flags: 0x8000000000000000() page dumped because: kasan: bad access detected Memory state around the buggy address: ffff8801b8947b80: f2 f2 f2 f2 00 00 00 00 00 04 f2 f2 f2 f2 f2 f2 ffff8801b8947c00: 00 00 00 00 00 00 00 00 f2 f2 f2 f2 00 00 00 00 >ffff8801b8947c80: 00 00 00 00 04 f2 f2 f2 00 00 00 00 00 00 00 00 ^ ffff8801b8947d00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff8801b8947d80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ==================================================================