drm/amdgpu: Fix snprintf usage in amdgpu_gfx_kiq_init_ring
This commit fixes a format truncation issue arosed by the snprintf function potentially writing more characters into the ring->name buffer than it can hold, in the amdgpu_gfx_kiq_init_ring function The issue occurred because the '%d' format specifier could write between 1 and 10 bytes into a region of size between 0 and 8, depending on the values of xcc_id, ring->me, ring->pipe, and ring->queue. The snprintf function could output between 12 and 41 bytes into a destination of size 16, leading to potential truncation. To resolve this, the snprintf line was modified to use the '%hhu' format specifier for xcc_id, ring->me, ring->pipe, and ring->queue. The '%hhu' specifier is used for unsigned char variables and ensures that these values are printed as unsigned decimal integers. Fixes the below with gcc W=1: drivers/gpu/drm/amd/amdgpu/amdgpu_gfx.c: In function ‘amdgpu_gfx_kiq_init_ring’: drivers/gpu/drm/amd/amdgpu/amdgpu_gfx.c:332:61: warning: ‘%d’ directive output may be truncated writing between 1 and 10 bytes into a region of size between 0 and 8 [-Wformat-truncation=] 332 | snprintf(ring->name, sizeof(ring->name), "kiq_%d.%d.%d.%d", | ^~ drivers/gpu/drm/amd/amdgpu/amdgpu_gfx.c:332:50: note: directive argument in the range [0, 2147483647] 332 | snprintf(ring->name, sizeof(ring->name), "kiq_%d.%d.%d.%d", | ^~~~~~~~~~~~~~~~~ drivers/gpu/drm/amd/amdgpu/amdgpu_gfx.c:332:9: note: ‘snprintf’ output between 12 and 41 bytes into a destination of size 16 332 | snprintf(ring->name, sizeof(ring->name), "kiq_%d.%d.%d.%d", | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ 333 | xcc_id, ring->me, ring->pipe, ring->queue); | ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Fixes: 345a36c4 ("drm/amdgpu: prefer snprintf over sprintf") Cc: Alex Deucher <alexander.deucher@amd.com> Cc: Christian König <christian.koenig@amd.com> Signed-off-by: Srinivasan Shanmugam <srinivasan.shanmugam@amd.com> Reviewed-by: Lijo Lazar <lijo.lazar@amd.com> Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
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