6.6-stable review patch. If anyone has any objections, please let me know.
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From: Srinivasan Shanmugam srinivasan.shanmugam@amd.com
[ Upstream commit acce6479e30f73ab0872e93a75aed1fb791d04ec ]
The function gfx_v9_4_3_init_microcode in gfx_v9_4_3.c was generating about potential truncation of output when using the snprintf function. The issue was due to the size of the buffer 'ucode_prefix' being too small to accommodate the maximum possible length of the string being written into it.
The string being written is "amdgpu/%s_mec.bin" or "amdgpu/%s_rlc.bin", where %s is replaced by the value of 'chip_name'. The length of this string without the %s is 16 characters. The warning message indicated that 'chip_name' could be up to 29 characters long, resulting in a total of 45 characters, which exceeds the buffer size of 30 characters.
To resolve this issue, the size of the 'ucode_prefix' buffer has been reduced from 30 to 15. This ensures that the maximum possible length of the string being written into the buffer will not exceed its size, thus preventing potential buffer overflow and truncation issues.
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@amd.com Cc: Christian König christian.koenig@amd.com Cc: Alex Deucher alexander.deucher@amd.com Cc: Lijo Lazar lijo.lazar@amd.com Signed-off-by: Srinivasan Shanmugam srinivasan.shanmugam@amd.com Suggested-by: Lijo Lazar lijo.lazar@amd.com Reviewed-by: Lijo Lazar lijo.lazar@amd.com Signed-off-by: Alex Deucher alexander.deucher@amd.com Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/gpu/drm/amd/amdgpu/gfx_v9_4_3.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
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 7c9a7ab9df3bb..af46823e43367 100644 --- a/drivers/gpu/drm/amd/amdgpu/gfx_v9_4_3.c +++ b/drivers/gpu/drm/amd/amdgpu/gfx_v9_4_3.c @@ -425,7 +425,7 @@ static int gfx_v9_4_3_init_cp_compute_microcode(struct amdgpu_device *adev,
static int gfx_v9_4_3_init_microcode(struct amdgpu_device *adev) { - char ucode_prefix[30]; + char ucode_prefix[15]; int r;
amdgpu_ucode_ip_version_decode(adev, GC_HWIP, ucode_prefix, sizeof(ucode_prefix));