fix RNG leak

Author: bigbrett

test/wh_test_crypto.c

@@ -142,6 +142,7 @@ static int whTest_CryptoRng(whClientContext* ctx, int devId, WC_RNG* rng)
     if (ret != 0) {
         WH_ERROR_PRINT("Failed to wc_InitRng_ex %d\n", ret);
     } else {
+        int freeRet;
         ret = wc_RNG_GenerateBlock(rng, lil, sizeof(lil));
         if (ret != 0) {
             WH_ERROR_PRINT("Failed to wc_RNG_GenerateBlock %d\n", ret);
@@ -162,9 +163,14 @@ static int whTest_CryptoRng(whClientContext* ctx, int devId, WC_RNG* rng)
                     ret = -1;
                 }
             }
-            ret = wc_FreeRng(rng);
-            if (ret != 0) {
-                WH_ERROR_PRINT("Failed to wc_FreeRng %d\n", ret);
+        }
+        /* Always free the RNG if InitRng succeeded, regardless of which (if
+         * any) GenerateBlock call failed. */
+        freeRet = wc_FreeRng(rng);
+        if (freeRet != 0) {
+            WH_ERROR_PRINT("Failed to wc_FreeRng %d\n", freeRet);
+            if (ret == 0) {
+                ret = freeRet;
             }
         }
     }