asn1/t_x509.c: fix serial number print, harmonize with a_int.c.

PR: 2675
Submitted by: Annie Yousar

crypto/asn1/a_int.c

@@ -386,8 +386,8 @@ long ASN1_INTEGER_get(const ASN1_INTEGER *a)
 	
 	if (a->length > (int)sizeof(long))
 		{
-		/* hmm... a bit ugly */
-		return(0xffffffffL);
+		/* hmm... a bit ugly, return all ones */
+		return -1;
 		}
 	if (a->data == NULL)
 		return 0;

crypto/asn1/t_x509.c

@@ -138,10 +138,10 @@ int X509_print_ex(BIO *bp, X509 *x, unsigned long nmflags, unsigned long cflag)
 		if (BIO_write(bp,"        Serial Number:",22) <= 0) goto err;
 
 		bs=X509_get_serialNumber(x);
-		if (bs->length <= 4)
+		if (bs->length <= sizeof(long))
 			{
 			l=ASN1_INTEGER_get(bs);
-			if (l < 0)
+			if (bs->type == V_ASN1_NEG_INTEGER)
 				{
 				l= -l;
 				neg="-";