diff --git a/net-libs/libnet/files/libnet-1.2-sizeof.patch b/net-libs/libnet/files/libnet-1.2-sizeof.patch
index e06dbb5bd7044..603224267fdf7 100644
--- a/net-libs/libnet/files/libnet-1.2-sizeof.patch
+++ b/net-libs/libnet/files/libnet-1.2-sizeof.patch
@@ -5,7 +5,7 @@
      if (payload_flag)
      {
 -	memset(cmd, 0, sizeof(cmd));
-+	memset(cmd, 0, sizeof(*cmd));
++	memset(cmd, 0, length);
  	memcpy(cmd, payload, (payload_s < 12 ? payload_s : 12));
  	length = payload_s;
      }