diff --git a/cpp/ql/test/query-tests/Security/CWE/CWE-190/semmle/TaintedAllocationSize/test.cpp b/cpp/ql/test/query-tests/Security/CWE/CWE-190/semmle/TaintedAllocationSize/test.cpp
index b11a136ed24a..b1245c6ae891 100644
--- a/cpp/ql/test/query-tests/Security/CWE/CWE-190/semmle/TaintedAllocationSize/test.cpp
+++ b/cpp/ql/test/query-tests/Security/CWE/CWE-190/semmle/TaintedAllocationSize/test.cpp
@@ -332,4 +332,13 @@ void ptr_diff_case() {
 	char* admin_begin_pos = strstr(user, "ADMIN");
 	int offset = admin_begin_pos ? user - admin_begin_pos : 0; 
 	malloc(offset); // GOOD
-}
\ No newline at end of file
+}
+
+void equality_barrier() {
+	int size1 = atoi(getenv("USER"));
+	int size2 = atoi(getenv("USER"));
+
+	if (size1 == size2) {
+		int* a = (int*)malloc(size1 * sizeof(int)); // GOOD
+	}
+}
diff --git a/cpp/ql/test/query-tests/Security/CWE/CWE-190/semmle/tainted/test.c b/cpp/ql/test/query-tests/Security/CWE/CWE-190/semmle/tainted/test.c
index 6999795b004f..29ab7cc8f25c 100644
--- a/cpp/ql/test/query-tests/Security/CWE/CWE-190/semmle/tainted/test.c
+++ b/cpp/ql/test/query-tests/Security/CWE/CWE-190/semmle/tainted/test.c
@@ -95,5 +95,12 @@ int main(int argc, char** argv) {
     }
   }
 
+  // GOOD: check the user input first
+  int maxConnections3 = atoi(argv[1]);
+  int maxConnections4 = atoi(argv[1]);
+  if (maxConnections3 == maxConnections4) {
+    startServer(maxConnections3 * 1000);
+  }
+
   return 0;
 }