Am 16.06.2016 um 09:54 schrieb Dan Carpenter:
On Thu, Jun 16, 2016 at 09:26:03AM +0200, walter harms wrote:
Am 16.06.2016 08:41, schrieb Dan Carpenter:
There is no limit on high "idx" can go. It should be less than ARRAY_SIZE(data.states) which is 16.
The "data" variable wasn't declared in that scope so I shifted the code around a bit to make it work.
Fixes: f3898ea12fc1 ('drm/amd/powerplay: add some sysfs interfaces for powerplay.') Signed-off-by: Dan Carpenter dan.carpenter@oracle.com
diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_pm.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_pm.c index 589b36e..ce9e97f 100644 --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_pm.c +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_pm.c @@ -275,25 +275,23 @@ static ssize_t amdgpu_set_pp_force_state(struct device *dev,
if (strlen(buf) == 1) adev->pp_force_state_enabled = false;
- else {
ret = kstrtol(buf, 0, &idx);
- else if (adev->pp_enabled) {
struct pp_states_info data;
if (ret) {
ret = kstrtol(buf, 0, &idx);if (ret || idx >= ARRAY_SIZE(data.states)) { count = -EINVAL; goto fail;i would also expect a check idx < 0, does it mean this can not happen ? otherwise maybe kstrtoul is a solution ?
The original code could underflow, but my code can't. ARRAY_SIZE() means the comparison is type promoted to size_t which is unsigned long.
That's probably true, but not very obvious (not that I understand much of the power related code anyway).
Using kstrtoul() in the first place would make it a bit less obscure and probably generate a nice error code when somebody really tries to use a negative index here.
Cheers, Christian.
regards, dan carpenter