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>
This commit is contained in:
Ernst Sjöstrand 2017-11-19 18:52:44 +01:00 committed by Alex Deucher
parent e9c227b253
commit 7d0331007a

View File

@ -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)
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) {