KEYS: Return more accurate error codes

We were using the wrong variable here so the error codes weren't being returned
properly.  The original code returns -ENOKEY.

Signed-off-by: Dan Carpenter <error27@gmail.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>
diff --git a/security/keys/process_keys.c b/security/keys/process_keys.c
index 06c2ccf..20a38fe 100644
--- a/security/keys/process_keys.c
+++ b/security/keys/process_keys.c
@@ -508,7 +508,7 @@
 
 			ret = install_thread_keyring();
 			if (ret < 0) {
-				key = ERR_PTR(ret);
+				key_ref = ERR_PTR(ret);
 				goto error;
 			}
 			goto reget_creds;
@@ -526,7 +526,7 @@
 
 			ret = install_process_keyring();
 			if (ret < 0) {
-				key = ERR_PTR(ret);
+				key_ref = ERR_PTR(ret);
 				goto error;
 			}
 			goto reget_creds;
@@ -585,7 +585,7 @@
 
 	case KEY_SPEC_GROUP_KEYRING:
 		/* group keyrings are not yet supported */
-		key = ERR_PTR(-EINVAL);
+		key_ref = ERR_PTR(-EINVAL);
 		goto error;
 
 	case KEY_SPEC_REQKEY_AUTH_KEY: