diff --git a/drivers/mmc/card/mmc_test.c b/drivers/mmc/card/mmc_test.c
index e27806d6458c..2888fdccd7ad 100644
--- a/drivers/mmc/card/mmc_test.c
+++ b/drivers/mmc/card/mmc_test.c
@@ -2024,9 +2024,10 @@ static ssize_t mmc_test_store(struct device *dev,
 {
 	struct mmc_card *card = mmc_dev_to_card(dev);
 	struct mmc_test_card *test;
-	int testcase;
+	long testcase;
 
-	testcase = simple_strtol(buf, NULL, 10);
+	if (strict_strtol(buf, 10, &testcase))
+		return -EINVAL;
 
 	test = kzalloc(sizeof(struct mmc_test_card), GFP_KERNEL);
 	if (!test)