drm/amdgpu: Fix truncation by resizing ucode_prefix in imu_v12_0_init_microcode

This commit fixes potential truncation when writing the string _imu.bin
into the fw_name buffer in the imu_v12_0_init_microcode function in the
imu_v12_0.c file

The ucode_prefix size was reduced from 30 to 15 to ensure the snprintf
function does not exceed the size of the fw_name buffer.

Thus fixing the below with gcc W=1:
drivers/gpu/drm/amd/amdgpu/imu_v12_0.c: In function ‘imu_v12_0_init_microcode’:
drivers/gpu/drm/amd/amdgpu/imu_v12_0.c:51:54: warning: ‘_imu.bin’ directive output may be truncated writing 8 bytes into a region of size between 4 and 33 [-Wformat-truncation=]
   51 |         snprintf(fw_name, sizeof(fw_name), "amdgpu/%s_imu.bin", ucode_prefix);
      |                                                      ^~~~~~~~
drivers/gpu/drm/amd/amdgpu/imu_v12_0.c:51:9: note: ‘snprintf’ output between 16 and 45 bytes into a destination of size 40
   51 |         snprintf(fw_name, sizeof(fw_name), "amdgpu/%s_imu.bin", ucode_prefix);
      |         ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Cc: Lijo Lazar <lijo.lazar@amd.com>
Cc: Christian König <christian.koenig@amd.com>
Cc: Alex Deucher <alexander.deucher@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>

diff --git a/drivers/gpu/drm/amd/amdgpu/imu_v12_0.c b/drivers/gpu/drm/amd/amdgpu/imu_v12_0.c
index ec2a4613567a0c9c9b5cbfa95e187c73f738266f..032ae12b2be2fbf25cd259ea2f1b3ac82c796f4c 100644 (file)
--- a/drivers/gpu/drm/amd/amdgpu/imu_v12_0.c
+++ b/drivers/gpu/drm/amd/amdgpu/imu_v12_0.c
@@ -39,7 +39,7 @@ MODULE_FIRMWARE("amdgpu/gc_12_0_1_imu.bin");
 static int imu_v12_0_init_microcode(struct amdgpu_device *adev)
 {
        char fw_name[40];
-       char ucode_prefix[30];
+       char ucode_prefix[15];
        int err;
        const struct imu_firmware_header_v1_0 *imu_hdr;
        struct amdgpu_firmware_info *info = NULL;