Re: [PATCH] drm/amdgpu: Fix truncation in gfx_v10_0_init_microcode

["Lazar, Lijo" <lijo.lazar@amd.com>]

On 3/22/2024 12:24 PM, Srinivasan Shanmugam wrote:
> The total size of the fw_name buffer is 8 (for "amdgpu/") + 30 (for
> ucode_prefix) + 5 (for "_pfp") + 5 (for "_wks") + 5 (for ".bin") = 53
> characters.
> 
> Fixes the below with gcc W=1:
> drivers/gpu/drm/amd/amdgpu/gfx_v10_0.c: In function ‘gfx_v10_0_early_init’:
> drivers/gpu/drm/amd/amdgpu/gfx_v10_0.c:3982:58: warning: ‘%s’ directive output may be truncated writing up to 4 bytes into a region of size between 0 and 29 [-Wformat-truncation=]
>  3982 |         snprintf(fw_name, sizeof(fw_name), "amdgpu/%s_pfp%s.bin", ucode_prefix, wks);
>       |                                                          ^~
> drivers/gpu/drm/amd/amdgpu/gfx_v10_0.c:3982:9: note: ‘snprintf’ output between 16 and 49 bytes into a destination of size 40
>  3982 |         snprintf(fw_name, sizeof(fw_name), "amdgpu/%s_pfp%s.bin", ucode_prefix, wks);
>       |         ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> drivers/gpu/drm/amd/amdgpu/gfx_v10_0.c:3988:57: warning: ‘%s’ directive output may be truncated writing up to 4 bytes into a region of size between 1 and 30 [-Wformat-truncation=]
>  3988 |         snprintf(fw_name, sizeof(fw_name), "amdgpu/%s_me%s.bin", ucode_prefix, wks);
>       |                                                         ^~
> drivers/gpu/drm/amd/amdgpu/gfx_v10_0.c:3988:9: note: ‘snprintf’ output between 15 and 48 bytes into a destination of size 40
>  3988 |         snprintf(fw_name, sizeof(fw_name), "amdgpu/%s_me%s.bin", ucode_prefix, wks);
>       |         ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> drivers/gpu/drm/amd/amdgpu/gfx_v10_0.c:3994:57: warning: ‘%s’ directive output may be truncated writing up to 4 bytes into a region of size between 1 and 30 [-Wformat-truncation=]
>  3994 |         snprintf(fw_name, sizeof(fw_name), "amdgpu/%s_ce%s.bin", ucode_prefix, wks);
>       |                                                         ^~
> drivers/gpu/drm/amd/amdgpu/gfx_v10_0.c:3994:9: note: ‘snprintf’ output between 15 and 48 bytes into a destination of size 40
>  3994 |         snprintf(fw_name, sizeof(fw_name), "amdgpu/%s_ce%s.bin", ucode_prefix, wks);
>       |         ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> drivers/gpu/drm/amd/amdgpu/gfx_v10_0.c:4001:62: warning: ‘_rlc.bin’ directive output may be truncated writing 8 bytes into a region of size between 4 and 33 [-Wformat-truncation=]
>  4001 |                 snprintf(fw_name, sizeof(fw_name), "amdgpu/%s_rlc.bin", ucode_prefix);
>       |                                                              ^~~~~~~~
> drivers/gpu/drm/amd/amdgpu/gfx_v10_0.c:4001:17: note: ‘snprintf’ output between 16 and 45 bytes into a destination of size 40
>  4001 |                 snprintf(fw_name, sizeof(fw_name), "amdgpu/%s_rlc.bin", ucode_prefix);
>       |                 ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> drivers/gpu/drm/amd/amdgpu/gfx_v10_0.c:4017:58: warning: ‘%s’ directive output may be truncated writing up to 4 bytes into a region of size between 0 and 29 [-Wformat-truncation=]
>  4017 |         snprintf(fw_name, sizeof(fw_name), "amdgpu/%s_mec%s.bin", ucode_prefix, wks);
>       |                                                          ^~
> drivers/gpu/drm/amd/amdgpu/gfx_v10_0.c:4017:9: note: ‘snprintf’ output between 16 and 49 bytes into a destination of size 40
>  4017 |         snprintf(fw_name, sizeof(fw_name), "amdgpu/%s_mec%s.bin", ucode_prefix, wks);
>       |         ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> drivers/gpu/drm/amd/amdgpu/gfx_v10_0.c:4024:54: warning: ‘_mec2’ directive output may be truncated writing 5 bytes into a region of size between 4 and 33 [-Wformat-truncation=]
>  4024 |         snprintf(fw_name, sizeof(fw_name), "amdgpu/%s_mec2%s.bin", ucode_prefix, wks);
>       |                                                      ^~~~~
> drivers/gpu/drm/amd/amdgpu/gfx_v10_0.c:4024:9: note: ‘snprintf’ output between 17 and 50 bytes into a destination of size 40
>  4024 |         snprintf(fw_name, sizeof(fw_name), "amdgpu/%s_mec2%s.bin", ucode_prefix, wks);
>       |         ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> 
> Cc: Alex Deucher <alexander.deucher@amd.com>
> Cc: Christian König <christian.koenig@amd.com>
> Suggested-by: Lijo Lazar <lijo.lazar@amd.com>
> Signed-off-by: Srinivasan Shanmugam <srinivasan.shanmugam@amd.com>

Reviewed-by: Lijo Lazar <lijo.lazar@amd.com>

Thanks,
Lijo
> ---
>  drivers/gpu/drm/amd/amdgpu/gfx_v10_0.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/gpu/drm/amd/amdgpu/gfx_v10_0.c b/drivers/gpu/drm/amd/amdgpu/gfx_v10_0.c
> index f90905ef32c7..d524f1a353ed 100644
> --- a/drivers/gpu/drm/amd/amdgpu/gfx_v10_0.c
> +++ b/drivers/gpu/drm/amd/amdgpu/gfx_v10_0.c
> @@ -3964,7 +3964,7 @@ static void gfx_v10_0_check_gfxoff_flag(struct amdgpu_device *adev)
>  
>  static int gfx_v10_0_init_microcode(struct amdgpu_device *adev)
>  {
> -	char fw_name[40];
> +	char fw_name[53];
>  	char ucode_prefix[30];
>  	const char *wks = "";
>  	int err;