[PATCH] drm/amdgpu: Fix format character cut-off issues in amdgpu_vcn_early_init()

[Christian König]

Am 20.03.24 um 09:45 schrieb Srinivasan Shanmugam:
> The issue was present in the lines where 'fw_name' was being formatted.
> This fix ensures that the output is not truncated
>
> Fixes the below with gcc W=1:
> drivers/gpu/drm/amd/amdgpu/amdgpu_vcn.c: In function ‘amdgpu_vcn_early_init’:
> drivers/gpu/drm/amd/amdgpu/amdgpu_vcn.c:102:66: warning: ‘snprintf’ output may be truncated before the last format character [-Wformat-truncation=]
>    102 |                 snprintf(fw_name, sizeof(fw_name), "amdgpu/%s.bin", ucode_prefix);
>        |                                                                  ^
> drivers/gpu/drm/amd/amdgpu/amdgpu_vcn.c:102:17: note: ‘snprintf’ output between 12 and 41 bytes into a destination of size 40
>    102 |                 snprintf(fw_name, sizeof(fw_name), "amdgpu/%s.bin", ucode_prefix);
>        |                 ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> drivers/gpu/drm/amd/amdgpu/amdgpu_vcn.c:102:66: warning: ‘snprintf’ output may be truncated before the last format character [-Wformat-truncation=]
>    102 |                 snprintf(fw_name, sizeof(fw_name), "amdgpu/%s.bin", ucode_prefix);
>        |                                                                  ^
> drivers/gpu/drm/amd/amdgpu/amdgpu_vcn.c:102:17: note: ‘snprintf’ output between 12 and 41 bytes into a destination of size 40
>    102 |                 snprintf(fw_name, sizeof(fw_name), "amdgpu/%s.bin", ucode_prefix);
>        |                 ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> drivers/gpu/drm/amd/amdgpu/amdgpu_vcn.c:105:73: warning: ‘.bin’ directive output may be truncated writing 4 bytes into a region of size between 2 and 31 [-Wformat-truncation=]
>    105 |                         snprintf(fw_name, sizeof(fw_name), "amdgpu/%s_%d.bin", ucode_prefix, i);
>        |                                                                         ^~~~
> drivers/gpu/drm/amd/amdgpu/amdgpu_vcn.c:105:25: note: ‘snprintf’ output between 14 and 43 bytes into a destination of size 40
>    105 |                         snprintf(fw_name, sizeof(fw_name), "amdgpu/%s_%d.bin", ucode_prefix, i);
>        |                         ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
>
> Cc: Alex Deucher <alexander.deucher at amd.com>
> Cc: Christian König <christian.koenig at amd.com>
> Suggested-by: Lijo Lazar <lijo.lazar at amd.com>
> Signed-off-by: Srinivasan Shanmugam <srinivasan.shanmugam at amd.com>

Acked-by: Christian König <christian.koenig at amd.com>

> ---
>   drivers/gpu/drm/amd/amdgpu/amdgpu_vcn.c | 2 +-
>   1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_vcn.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_vcn.c
> index 9c514a606a2f..f994ee6c548d 100644
> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_vcn.c
> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_vcn.c
> @@ -94,7 +94,7 @@ static void amdgpu_vcn_idle_work_handler(struct work_struct *work);
>   int amdgpu_vcn_early_init(struct amdgpu_device *adev)
>   {
>   	char ucode_prefix[30];
> -	char fw_name[40];
> +	char fw_name[42];
>   	int r, i;
>   
>   	for (i = 0; i < adev->vcn.num_vcn_inst; i++) {