diff --git a/src/dhcp6relay/src/relay.cpp b/src/dhcp6relay/src/relay.cpp index e2eb8e4fac..3e9c9520e6 100644 --- a/src/dhcp6relay/src/relay.cpp +++ b/src/dhcp6relay/src/relay.cpp @@ -515,14 +515,16 @@ void relay_client(int sock, const uint8_t *msg, int32_t len, const ip6_hdr *ip_h void callback(evutil_socket_t fd, short event, void *arg) { struct relay_config *config = (struct relay_config *)arg; static uint8_t message_buffer[4096]; - uint32_t len = recv(config->filter, message_buffer, 4096, 0); + int32_t len = recv(config->filter, message_buffer, 4096, 0); if (len <= 0) { - syslog(LOG_WARNING, "recv: Failed to receive data at filter socket\n"); + syslog(LOG_WARNING, "recv: Failed to receive data at filter socket: %s\n", strerror(errno)); + return; } char* ptr = (char *)message_buffer; - const uint8_t *current_position = (uint8_t *)ptr; + const uint8_t *current_position = (uint8_t *)ptr; const uint8_t *tmp = NULL; + const uint8_t *prev = NULL; auto ether_header = parse_ether_frame(current_position, &tmp); current_position = tmp; @@ -530,14 +532,19 @@ void callback(evutil_socket_t fd, short event, void *arg) { auto ip_header = parse_ip6_hdr(current_position, &tmp); current_position = tmp; + prev = current_position; if (ip_header->ip6_ctlun.ip6_un1.ip6_un1_nxt != IPPROTO_UDP) { const struct ip6_ext *ext_header; do { ext_header = (const struct ip6_ext *)current_position; current_position += ext_header->ip6e_len; + if((current_position == prev) || (current_position >= (uint8_t *)ptr + sizeof(message_buffer))) { + return; + } + prev = current_position; } while (ext_header->ip6e_nxt != IPPROTO_UDP); - } + } auto udp_header = parse_udp(current_position, &tmp); current_position = tmp;