uhcp: fix handling of pushed prefix

RIOT-OS · Nov 24, 2020 · 2d54968 · 2d54968
1 parent ea84953
commit 2d54968
Showing 1 changed file with 5 additions and 2 deletions.
diff --git a/sys/net/application_layer/uhcp/uhcp.c b/sys/net/application_layer/uhcp/uhcp.c
@@ -97,9 +97,12 @@ void uhcp_handle_push(uhcp_push_t *req, uint8_t *src, uint16_t port, uhcp_iface_
     char addr_str[INET6_ADDRSTRLEN];
     char prefix_str[INET6_ADDRSTRLEN];
     inet_ntop(AF_INET6, src, addr_str, INET6_ADDRSTRLEN);
-    uint8_t prefix[16];
+    uint8_t prefix[IN6ADDRSZ] = { 0 };
+    if (req->prefix_len == 0) {
+        LOG_ERROR("uhcp_handle_push(): prefix length 0\n");
+        return;
+    }
     size_t prefix_bytes = (req->prefix_len + 7)>>3;
-    memset(prefix + 16 - prefix_bytes, '\0', 16 - prefix_bytes);
     memcpy(prefix, req->prefix, prefix_bytes);
 
     inet_ntop(AF_INET6, prefix, prefix_str, INET6_ADDRSTRLEN);