On 4/23/2024 7:13 AM, Srinivasan Shanmugam wrote:
> The buffer size is determined by the declaration char fw_name[30]; This
> means fw_name can hold up to 30 characters, including the null character
> that marks the end of the string.
>
> The string to be written is "amdgpu/%s_mec.bin" or "amdgpu/%s_rlc.bin",
> where %s will be replaced by the value of chip_name.
>
> The length of the string "amdgpu/%s_mec.bin" or "amdgpu/%s_rlc.bin"
> without the %s is 16 characters.
>
> The warning message is saying that the chip_name could be up to 29
> characters long. If we add the 16 characters from the string
> "amdgpu/%s_mec.bin" or "amdgpu/%s_rlc.bin", we get a total of 45
> characters.
>
> This is potentially longer than the buffer size of 30 characters.
>
> if chip_name is longer than 14 characters (30 buffer size - 16
> characters from the string), the resulting string will not fit into the
> fw_name buffer, Thus increasing fw_name buffer size to 50
>
> Fixes the below with gcc W=1:
> drivers/gpu/drm/amd/amdgpu/gfx_v9_4_3.c: In function ‘gfx_v9_4_3_early_init’:
> drivers/gpu/drm/amd/amdgpu/gfx_v9_4_3.c:379:52: warning: ‘%s’ directive output may be truncated writing up to 29 bytes into a region of size 23 [-Wformat-truncation=]
> 379 | snprintf(fw_name, sizeof(fw_name), "amdgpu/%s_rlc.bin", chip_name);
> | ^~
> ......
> 439 | r = gfx_v9_4_3_init_rlc_microcode(adev, ucode_prefix);
> | ~~~~~~~~~~~~
> drivers/gpu/drm/amd/amdgpu/gfx_v9_4_3.c:379:9: note: ‘snprintf’ output between 16 and 45 bytes into a destination of size 30
> 379 | snprintf(fw_name, sizeof(fw_name), "amdgpu/%s_rlc.bin", chip_name);
> | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> drivers/gpu/drm/amd/amdgpu/gfx_v9_4_3.c:413:52: warning: ‘%s’ directive output may be truncated writing up to 29 bytes into a region of size 23 [-Wformat-truncation=]
> 413 | snprintf(fw_name, sizeof(fw_name), "amdgpu/%s_mec.bin", chip_name);
> | ^~
> ......
> 443 | r = gfx_v9_4_3_init_cp_compute_microcode(adev, ucode_prefix);
> | ~~~~~~~~~~~~
> drivers/gpu/drm/amd/amdgpu/gfx_v9_4_3.c:413:9: note: ‘snprintf’ output between 16 and 45 bytes into a destination of size 30
> 413 | snprintf(fw_name, sizeof(fw_name), "amdgpu/%s_mec.bin", chip_name);
> | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
>
> Fixes: 86301129698b ("drm/amdgpu: split gc v9_4_3 functionality from gc v9_0")
> Cc: Hawking Zhang <Hawking.Zhang@xxxxxxx>
> Cc: Christian König <christian.koenig@xxxxxxx>
> Cc: Alex Deucher <alexander.deucher@xxxxxxx>
> Cc: Lijo Lazar <lijo.lazar@xxxxxxx>
> Signed-off-by: Srinivasan Shanmugam <srinivasan.shanmugam@xxxxxxx>
> ---
> drivers/gpu/drm/amd/amdgpu/gfx_v9_4_3.c | 4 ++--
> 1 file changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/gpu/drm/amd/amdgpu/gfx_v9_4_3.c b/drivers/gpu/drm/amd/amdgpu/gfx_v9_4_3.c
> index 0e429b7ed036..1c46d5f6677f 100644
> --- a/drivers/gpu/drm/amd/amdgpu/gfx_v9_4_3.c
> +++ b/drivers/gpu/drm/amd/amdgpu/gfx_v9_4_3.c
> @@ -370,7 +370,7 @@ static void gfx_v9_4_3_free_microcode(struct amdgpu_device *adev)
> static int gfx_v9_4_3_init_rlc_microcode(struct amdgpu_device *adev,
> const char *chip_name)
> {
> - char fw_name[30];
> + char fw_name[50];
Thanks for the patch. You may solve this by changing ucode_prefix to 15
in gfx_v9_4_3_init_microcode.
Thanks,
Lijo
> int err;
> const struct rlc_firmware_header_v2_0 *rlc_hdr;
> uint16_t version_major;
> @@ -407,7 +407,7 @@ static void gfx_v9_4_3_check_if_need_gfxoff(struct amdgpu_device *adev)
> static int gfx_v9_4_3_init_cp_compute_microcode(struct amdgpu_device *adev,
> const char *chip_name)
> {
> - char fw_name[30];
> + char fw_name[50];
> int err;
>
> snprintf(fw_name, sizeof(fw_name), "amdgpu/%s_mec.bin", chip_name);
