[CIFS] oid should also be checked against class in cifs asn

The oid coming back from asn1_header_decode is a primitive object so
class should be checked to be universal.
Acked-by: Love Hörnquist Åstrand <lha@kth.se>
Signed-off-by: Steve French <sfrench@us.ibm.com>

fs/cifs/asn1.c

@@ -494,7 +494,8 @@ decode_negTokenInit(unsigned char *security_blob, int length,
 		/*      remember to free obj->oid */
 		rc = asn1_header_decode(&ctx, &end, &cls, &con, &tag);
 		if (rc) {
-			if ((tag == ASN1_OJI) && (con == ASN1_PRI)) {
+			if ((tag == ASN1_OJI) && (con == ASN1_PRI) &&
+			    (cls == ASN1_UNI)) {
 				rc = asn1_oid_decode(&ctx, end, &oid, &oidlen);
 				if (rc) {
 					rc = compare_oid(oid, oidlen,