s390/dasd: Remove variable sized array

Dynamic stack allocations are considered bad. Get rid of this one
occurrence and use kstrdup() instead.

Also, set the return codes so that we have only one exit where we can
call kfree().
Signed-off-by: NJan Höppner <hoeppner@linux.vnet.ibm.com>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

drivers/s390/block/dasd_devmap.c

@@ -315,45 +315,58 @@ static int __init dasd_parse_range(const char *range)
 	char *features_str = NULL;
 	char *from_str = NULL;
 	char *to_str = NULL;
-	size_t len = strlen(range) + 1;
-	char tmp[len];
+	int rc = 0;
+	char *tmp;
 
-	strlcpy(tmp, range, len);
+	tmp = kstrdup(range, GFP_KERNEL);
+	if (!tmp)
+		return -ENOMEM;
 
-	if (dasd_evaluate_range_param(tmp, &from_str, &to_str, &features_str))
-		goto out_err;
+	if (dasd_evaluate_range_param(tmp, &from_str, &to_str, &features_str)) {
+		rc = -EINVAL;
+		goto out;
+	}
 
-	if (dasd_busid(from_str, &from_id0, &from_id1, &from))
-		goto out_err;
+	if (dasd_busid(from_str, &from_id0, &from_id1, &from)) {
+		rc = -EINVAL;
+		goto out;
+	}
 
 	to = from;
 	to_id0 = from_id0;
 	to_id1 = from_id1;
 	if (to_str) {
-		if (dasd_busid(to_str, &to_id0, &to_id1, &to))
-			goto out_err;
+		if (dasd_busid(to_str, &to_id0, &to_id1, &to)) {
+			rc = -EINVAL;
+			goto out;
+		}
 		if (from_id0 != to_id0 || from_id1 != to_id1 || from > to) {
 			pr_err("%s is not a valid device range\n", range);
-			goto out_err;
+			rc = -EINVAL;
+			goto out;
 		}
 	}
 
 	features = dasd_feature_list(features_str);
-	if (features < 0)
-		goto out_err;
+	if (features < 0) {
+		rc = -EINVAL;
+		goto out;
+	}
 	/* each device in dasd= parameter should be set initially online */
 	features |= DASD_FEATURE_INITIAL_ONLINE;
 	while (from <= to) {
 		sprintf(bus_id, "%01x.%01x.%04x", from_id0, from_id1, from++);
 		devmap = dasd_add_busid(bus_id, features);
-		if (IS_ERR(devmap))
-			return PTR_ERR(devmap);
+		if (IS_ERR(devmap)) {
+			rc = PTR_ERR(devmap);
+			goto out;
+		}
 	}
 
-	return 0;
+out:
+	kfree(tmp);
 
-out_err:
-	return -EINVAL;
+	return rc;
 }
 
 /*