drm/amd/amdgpu: Fix missing null check in atombios_i2c.c
Reported by smatch:
amdgpu_atombios_i2c_process_i2c_ch() error: we previously assumed 'buf' could be null
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Ernst Sjöstrand <ernstp@gmail.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
diff --git a/drivers/gpu/drm/amd/amdgpu/atombios_i2c.c b/drivers/gpu/drm/amd/amdgpu/atombios_i2c.c
index b374653..f9b2ce9 100644
--- a/drivers/gpu/drm/amd/amdgpu/atombios_i2c.c
+++ b/drivers/gpu/drm/amd/amdgpu/atombios_i2c.c
@@ -65,8 +65,15 @@ static int amdgpu_atombios_i2c_process_i2c_ch(struct amdgpu_i2c_chan *chan,
args.ucRegIndex = buf[0];
if (num)
num--;
- if (num)
- memcpy(&out, &buf[1], num);
+ if (num) {
+ if (buf) {
+ memcpy(&out, &buf[1], num);
+ } else {
+ DRM_ERROR("hw i2c: missing buf with num > 1\n");
+ r = -EINVAL;
+ goto done;
+ }
+ }
args.lpI2CDataOut = cpu_to_le16(out);
} else {
if (num > ATOM_MAX_HW_I2C_READ) {