Check for failures, to avoid memory leak

Thanks to Jiecheng Wu, Zuxing Gu for the report.
Reviewed-by: NAndy Polyakov <appro@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/6791)

crypto/ec/ec_ameth.c

@@ -92,19 +92,19 @@ static int eckey_pub_encode(X509_PUBKEY *pk, const EVP_PKEY *pkey)
 static EC_KEY *eckey_type2param(int ptype, const void *pval)
 {
     EC_KEY *eckey = NULL;
+    EC_GROUP *group = NULL;
+
     if (ptype == V_ASN1_SEQUENCE) {
         const ASN1_STRING *pstr = pval;
-        const unsigned char *pm = NULL;
-        int pmlen;
-        pm = pstr->data;
-        pmlen = pstr->length;
+        const unsigned char *pm = pstr->data;
+        int pmlen = pstr->length;
+
         if ((eckey = d2i_ECParameters(NULL, &pm, pmlen)) == NULL) {
             ECerr(EC_F_ECKEY_TYPE2PARAM, EC_R_DECODE_ERROR);
             goto ecerr;
         }
     } else if (ptype == V_ASN1_OBJECT) {
         const ASN1_OBJECT *poid = pval;
-        EC_GROUP *group;
 
         /*
          * type == V_ASN1_OBJECT => the parameters are given by an asn1 OID
@@ -129,6 +129,7 @@ static EC_KEY *eckey_type2param(int ptype, const void *pval)
 
  ecerr:
     EC_KEY_free(eckey);
+    EC_GROUP_free(group);
     return NULL;
 }
 

crypto/x509v3/v3_tlsf.c

@@ -122,13 +122,12 @@ static TLS_FEATURE *v2i_TLS_FEATURE(const X509V3_EXT_METHOD *method,
             }
         }
 
-        ai = ASN1_INTEGER_new();
-        if (ai == NULL) {
+        if ((ai = ASN1_INTEGER_new()) == NULL
+                || !ASN1_INTEGER_set(ai, tlsextid)
+                || sk_ASN1_INTEGER_push(tlsf, ai) <= 0) {
             X509V3err(X509V3_F_V2I_TLS_FEATURE, ERR_R_MALLOC_FAILURE);
             goto err;
         }
-        ASN1_INTEGER_set(ai, tlsextid);
-        sk_ASN1_INTEGER_push(tlsf, ai);
     }
     return tlsf;