[PATCH 10/10] block: replace sscanf() with kstrtoint() in part_fail_store()

[Jackie Liu <liu.yun@linux.dev>]

From: Jackie Liu <liuyun01@kylinos.cn>

sscanf() is overly lenient for parsing a single integer from sysfs.
Use kstrtoint() which also properly rejects malformed input and
makes the count > 0 guard unnecessary.

Signed-off-by: Jackie Liu <liuyun01@kylinos.cn>
---
 block/genhd.c | 16 +++++++++-------
 1 file changed, 9 insertions(+), 7 deletions(-)

diff --git a/block/genhd.c b/block/genhd.c
index 7d6854fd28e9..369bd8c13bbf 100644
--- a/block/genhd.c
+++ b/block/genhd.c
@@ -1186,14 +1186,16 @@ ssize_t part_fail_store(struct device *dev,
 			struct device_attribute *attr,
 			const char *buf, size_t count)
 {
-	int i;
+	int val;
+
+	if (kstrtoint(buf, 10, &val))
+		return -EINVAL;
+
+	if (val)
+		bdev_set_flag(dev_to_bdev(dev), BD_MAKE_IT_FAIL);
+	else
+		bdev_clear_flag(dev_to_bdev(dev), BD_MAKE_IT_FAIL);
 
-	if (count > 0 && sscanf(buf, "%d", &i) > 0) {
-		if (i)
-			bdev_set_flag(dev_to_bdev(dev), BD_MAKE_IT_FAIL);
-		else
-			bdev_clear_flag(dev_to_bdev(dev), BD_MAKE_IT_FAIL);
-	}
 	return count;
 }
 
-- 
2.51.1