On Thu, May 23, 2024 at 06:51:08PM +0300, Jani Nikula wrote:
> Enabling -Wformat-truncation yields the following warning:
>
> ../drivers/gpu/drm/imx/ipuv3/imx-ldb.c: In function ‘imx_ldb_probe’:
> ../drivers/gpu/drm/imx/ipuv3/imx-ldb.c:658:57: error: ‘_sel’ directive output may be truncated writing 4 bytes into a region of size between 3 and 13 [-Werror=format-truncation=]
> 658 | snprintf(clkname, sizeof(clkname), "di%d_sel", i);
> | ^~~~
> ../drivers/gpu/drm/imx/ipuv3/imx-ldb.c:658:17: note: ‘snprintf’ output between 8 and 18 bytes into a destination of size 16
> 658 | snprintf(clkname, sizeof(clkname), "di%d_sel", i);
> | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
If only the compiler could count to three...
>
> Silence the warning by checking the snprintf() return value.
>
> Signed-off-by: Jani Nikula <jani.nikula@xxxxxxxxx>
>
> ---
>
> Cc: Philipp Zabel <p.zabel@xxxxxxxxxxxxxx>
> Cc: Shawn Guo <shawnguo@xxxxxxxxxx>
> Cc: Sascha Hauer <s.hauer@xxxxxxxxxxxxxx>
> Cc: Pengutronix Kernel Team <kernel@xxxxxxxxxxxxxx>
> Cc: Fabio Estevam <festevam@xxxxxxxxx>
> Cc: dri-devel@xxxxxxxxxxxxxxxxxxxxx
> Cc: imx@xxxxxxxxxxxxxxx
> ---
> drivers/gpu/drm/imx/ipuv3/imx-ldb.c | 6 +++++-
> 1 file changed, 5 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/gpu/drm/imx/ipuv3/imx-ldb.c b/drivers/gpu/drm/imx/ipuv3/imx-ldb.c
> index 71d70194fcbd..46f779fe60ee 100644
> --- a/drivers/gpu/drm/imx/ipuv3/imx-ldb.c
> +++ b/drivers/gpu/drm/imx/ipuv3/imx-ldb.c
> @@ -654,8 +654,12 @@ static int imx_ldb_probe(struct platform_device *pdev)
> */
> for (i = 0; i < 4; i++) {
> char clkname[16];
> + int len;
> +
> + len = snprintf(clkname, sizeof(clkname), "di%d_sel", i);
> + if (len >= sizeof(clkname))
> + dev_err(dev, "clkname truncated\n");
>
> - snprintf(clkname, sizeof(clkname), "di%d_sel", i);
> imx_ldb->clk_sel[i] = devm_clk_get(imx_ldb->dev, clkname);
> if (IS_ERR(imx_ldb->clk_sel[i])) {
> ret = PTR_ERR(imx_ldb->clk_sel[i]);
> --
> 2.39.2
--
Ville Syrjälä
Intel
