Re: [PATCH V2 1/2] OPP: debugfs: Fix warning with W=1 builds

[Dhruva Gole]

Hi,

On 04/03/24 16:52, Viresh Kumar wrote:
> We currently get the following warning:
>
> debugfs.c:105:54: error: '%d' directive output may be truncated writing between 1 and 11 bytes into a region of size 8 [-Werror=format-truncation=]
>                   snprintf(name, sizeof(name), "supply-%d", i);
>                                                        ^~
> debugfs.c:105:46: note: directive argument in the range [-2147483644, 2147483646]
>                   snprintf(name, sizeof(name), "supply-%d", i);
>                                                ^~~~~~~~~~~
> debugfs.c:105:17: note: 'snprintf' output between 9 and 19 bytes into a destination of size 15
>                   snprintf(name, sizeof(name), "supply-%d", i);
>
> Fix this and another potential issues it by allocating larger arrays.

Just to keep in mind while applying maybe: s/another/other

> Use the exact string format to allocate the arrays without getting into
> these issues again.
> Reported-by: kernel test robot <lkp@xxxxxxxxx>
> Closes: https://lore.kernel.org/oe-kbuild-all/202402141313.81ltVF5g-lkp@xxxxxxxxx/
> Signed-off-by: Viresh Kumar <viresh.kumar@xxxxxxxxxx>
> ---
> V2: Use string name while allocating memory for the array to fix potential
> issues later on.
>
>   drivers/opp/debugfs.c | 8 ++++----
>   1 file changed, 4 insertions(+), 4 deletions(-)
>
> diff --git a/drivers/opp/debugfs.c b/drivers/opp/debugfs.c
> index ec030b19164a..27c3748347af 100644
> --- a/drivers/opp/debugfs.c
> +++ b/drivers/opp/debugfs.c
> @@ -56,11 +56,11 @@ static void opp_debug_create_bw(struct dev_pm_opp *opp,
>   				struct dentry *pdentry)
>   {
>   	struct dentry *d;
> -	char name[20];
> +	char name[] = "icc-path-XXXXXXXXXX"; /* Integers can take 10 chars max */

LGTM!

>   	int i;
>   
>   	for (i = 0; i < opp_table->path_count; i++) {
> -		snprintf(name, sizeof(name), "icc-path-%.1d", i);
> +		snprintf(name, sizeof(name), "icc-path-%d", i);
>   
>   		/* Create per-path directory */
>   		d = debugfs_create_dir(name, pdentry);
> @@ -78,7 +78,7 @@ static void opp_debug_create_clks(struct dev_pm_opp *opp,
>   				  struct opp_table *opp_table,
>   				  struct dentry *pdentry)
>   {
> -	char name[12];
> +	char name[] = "rate_hz_XXXXXXXXXX"; /* Integers can take 10 chars max */
>   	int i;
>   
>   	if (opp_table->clk_count == 1) {
> @@ -100,7 +100,7 @@ static void opp_debug_create_supplies(struct dev_pm_opp *opp,
>   	int i;
>   
>   	for (i = 0; i < opp_table->regulator_count; i++) {
> -		char name[15];
> +		char name[] = "supply-XXXXXXXXXX"; /* Integers can take 10 chars max */

Feels like a better solution to me than the previous revision, thanks!


Reviewed-by: Dhruva Gole <d-gole@xxxxxx>

>   
>   		snprintf(name, sizeof(name), "supply-%d", i);
>   

--
Thanks and Regards,
Dhruva Gole