Fix a memory leak in EC_GROUP_get_ecparameters()

The variable 'buffer', allocated by EC_POINT_point2buf(), isn't
free'd on the success path.
Reviewed-by: NRich Salz <rsalz@openssl.org>
Reviewed-by: NMatt Caswell <matt@openssl.org>

crypto/ec/ec_asn1.c

@@ -512,13 +512,11 @@ ECPARAMETERS *EC_GROUP_get_ecparameters(const EC_GROUP *group,
         goto err;
     }
     if (ret->base == NULL && (ret->base = ASN1_OCTET_STRING_new()) == NULL) {
+        OPENSSL_free(buffer);
         ECerr(EC_F_EC_GROUP_GET_ECPARAMETERS, ERR_R_MALLOC_FAILURE);
         goto err;
     }
-    if (!ASN1_OCTET_STRING_set(ret->base, buffer, len)) {
-        ECerr(EC_F_EC_GROUP_GET_ECPARAMETERS, ERR_R_ASN1_LIB);
-        goto err;
-    }
+    ASN1_STRING_set0(ret->base, buffer, len);
 
     /* set the order */
     tmp = EC_GROUP_get0_order(group);
@@ -547,7 +545,6 @@ ECPARAMETERS *EC_GROUP_get_ecparameters(const EC_GROUP *group,
  err:
     if (params == NULL)
         ECPARAMETERS_free(ret);
-    OPENSSL_free(buffer);
     return NULL;
 }
 

test/ectest.c

@@ -1712,6 +1712,33 @@ static void nistp_tests()
 }
 # endif
 
+static void parameter_test(void)
+{
+    EC_GROUP *group, *group2;
+    ECPARAMETERS *ecparameters;
+
+    fprintf(stderr, "\ntesting ecparameters conversion ...");
+
+    group = EC_GROUP_new_by_curve_name(NID_secp112r1);
+    if (!group)
+        ABORT;
+
+    ecparameters = EC_GROUP_get_ecparameters(group, NULL);
+    if (!ecparameters)
+        ABORT;
+    group2 = EC_GROUP_new_from_ecparameters(ecparameters);
+    if (!group2)
+        ABORT;
+    if (EC_GROUP_cmp(group, group2, NULL))
+        ABORT;
+
+    fprintf(stderr, " ok\n");
+
+    EC_GROUP_free(group);
+    EC_GROUP_free(group2);
+    ECPARAMETERS_free(ecparameters);
+}
+
 static const char rnd_seed[] =
     "string to make the random number generator think it has entropy";
 
@@ -1737,6 +1764,8 @@ int main(int argc, char *argv[])
     /* test the internal curves */
     internal_curve_test();
 
+    parameter_test();
+
 #ifndef OPENSSL_NO_CRYPTO_MDEBUG
     if (CRYPTO_mem_leaks_fp(stderr) <= 0)
         return 1;