static unsigned int help(struct sk_buff *skb,
			 enum ip_conntrack_info ctinfo,
			 unsigned int protoff,
			 unsigned int matchoff,
			 unsigned int matchlen,
 			 struct nf_conntrack_expect *exp)
 {
 	char buffer[sizeof("4294967296 65635")];
 	u_int16_t port;
 	unsigned int ret;
 
 	/* Reply comes from server. */
 	exp->saved_proto.tcp.port = exp->tuple.dst.u.tcp.port;
 	exp->dir = IP_CT_DIR_REPLY;
 	exp->expectfn = nf_nat_follow_master;

	/* Try to get same port: if not, try to change it. */
	for (port = ntohs(exp->saved_proto.tcp.port); port != 0; port++) {
		int ret;

		exp->tuple.dst.u.tcp.port = htons(port);
		ret = nf_ct_expect_related(exp);
		if (ret == 0)
			break;
		else if (ret != -EBUSY) {
			port = 0;
			break;
		}
 	}
 
 	if (port == 0) {
		nf_ct_helper_log(skb, exp->master, "all ports in use");
 		return NF_DROP;
 	}
 
	ret = nf_nat_mangle_tcp_packet(skb, exp->master, ctinfo,
				       protoff, matchoff, matchlen, buffer,
				       strlen(buffer));
 	if (ret != NF_ACCEPT) {
		nf_ct_helper_log(skb, exp->master, "cannot mangle packet");
 		nf_ct_unexpect_related(exp);
 	}
 	return ret;
 }

The product performs operations on a memory buffer, but it reads from or writes to a memory location outside the buffer's intended boundary. This may result in read or write operations on unexpected memory locations that could be linked to other variables, data structures, or internal program data.