[PATCH 1/9] loop: use sysfs_emit() in the sysfs offset show

[Chaitanya Kulkarni <chaitanya.kulkarni@xxxxxxx>]

Output defects can exist in sysfs content using sprintf and snprintf.

sprintf does not know the PAGE_SIZE maximum of the temporary buffer
used for outputting sysfs content and it's possible to overrun the
PAGE_SIZE buffer length.

Use a generic sysfs_emit function that knows that the size of the
temporary buffer and ensures that no overrun is done for offset
attribute.

Signed-off-by: Chaitanya Kulkarni <chaitanya.kulkarni@xxxxxxx>
---
 drivers/block/loop.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/block/loop.c b/drivers/block/loop.c
index 081eb9aaeba8..847faa6c48fc 100644
--- a/drivers/block/loop.c
+++ b/drivers/block/loop.c
@@ -807,7 +807,7 @@ static ssize_t loop_attr_backing_file_show(struct loop_device *lo, char *buf)
 
 static ssize_t loop_attr_offset_show(struct loop_device *lo, char *buf)
 {
-	return sprintf(buf, "%llu\n", (unsigned long long)lo->lo_offset);
+	return sysfs_emit(buf, "%llu\n", (unsigned long long)lo->lo_offset);
 }
 
 static ssize_t loop_attr_sizelimit_show(struct loop_device *lo, char *buf)
-- 
2.22.1