> On Sep 21, 2021, at 4:21 AM, Chaitanya Kulkarni <chaitanyak@xxxxxxxxxx> wrote:
>
> From: Chaitanya Kulkarni <kch@xxxxxxxxxx>
>
> 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 dio
> attribute.
>
> Signed-off-by: Chaitanya Kulkarni <kch@xxxxxxxxxx>
> ---
> 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 63f64341c19c..fedb8d63b4c6 100644
> --- a/drivers/block/loop.c
> +++ b/drivers/block/loop.c
> @@ -882,7 +882,7 @@ static ssize_t loop_attr_dio_show(struct loop_device *lo, char *buf)
> {
> int dio = (lo->lo_flags & LO_FLAGS_DIRECT_IO);
>
> - return sprintf(buf, "%s\n", dio ? "1" : "0");
> + return sysfs_emit(buf, "%s\n", dio ? "1" : "0");
> }
>
> LOOP_ATTR_RO(backing_file);
> --
> 2.29.0
>
After fixing small nits noted in patch 1 you can add
Reviewed-by: Himanshu Madhani <himanshu.madhani@xxxxxxxxxx>
--
Himanshu Madhani Oracle Linux Engineering
