selinux: minor tweaks to selinux_add_opt()

Two minor edits to selinux_add_opt(): use "sizeof(*ptr)" instead of
"sizeof(type)" in the kzalloc() call, and rename the "Einval" jump
target to "err" for the sake of consistency.
Signed-off-by: Paul Moore <paul@paul-moore.com>

security/selinux/hooks.c

@@ -972,14 +972,14 @@ static int selinux_add_opt(int token, const char *s, void **mnt_opts)
 	struct selinux_mnt_opts *opts = *mnt_opts;
 	bool is_alloc_opts = false;
 
-	if (token == Opt_seclabel)	/* eaten and completely ignored */
+	if (token == Opt_seclabel)
+		/* eaten and completely ignored */
 		return 0;
-
 	if (!s)
 		return -ENOMEM;
 
 	if (!opts) {
-		opts = kzalloc(sizeof(struct selinux_mnt_opts), GFP_KERNEL);
+		opts = kzalloc(sizeof(*opts), GFP_KERNEL);
 		if (!opts)
 			return -ENOMEM;
 		*mnt_opts = opts;
@@ -989,27 +989,29 @@ static int selinux_add_opt(int token, const char *s, void **mnt_opts)
 	switch (token) {
 	case Opt_context:
 		if (opts->context || opts->defcontext)
-			goto Einval;
+			goto err;
 		opts->context = s;
 		break;
 	case Opt_fscontext:
 		if (opts->fscontext)
-			goto Einval;
+			goto err;
 		opts->fscontext = s;
 		break;
 	case Opt_rootcontext:
 		if (opts->rootcontext)
-			goto Einval;
+			goto err;
 		opts->rootcontext = s;
 		break;
 	case Opt_defcontext:
 		if (opts->context || opts->defcontext)
-			goto Einval;
+			goto err;
 		opts->defcontext = s;
 		break;
 	}
+
 	return 0;
-Einval:
+
+err:
 	if (is_alloc_opts) {
 		kfree(opts);
 		*mnt_opts = NULL;