Message ID | 20160616064119.GA23129@mwanda (mailing list archive) |
---|---|
State | New, archived |
Headers | show |
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 ? re, wh > > - if (adev->pp_enabled) { > - struct pp_states_info data; > - amdgpu_dpm_get_pp_num_states(adev, &data); > - state = data.states[idx]; > - /* only set user selected power states */ > - if (state != POWER_STATE_TYPE_INTERNAL_BOOT && > - state != POWER_STATE_TYPE_DEFAULT) { > - amdgpu_dpm_dispatch_task(adev, > - AMD_PP_EVENT_ENABLE_USER_STATE, &state, NULL); > - adev->pp_force_state_enabled = true; > - } > + amdgpu_dpm_get_pp_num_states(adev, &data); > + state = data.states[idx]; > + /* only set user selected power states */ > + if (state != POWER_STATE_TYPE_INTERNAL_BOOT && > + state != POWER_STATE_TYPE_DEFAULT) { > + amdgpu_dpm_dispatch_task(adev, > + AMD_PP_EVENT_ENABLE_USER_STATE, &state, NULL); > + adev->pp_force_state_enabled = true; > } > } > fail: > -- > To unsubscribe from this list: send the line "unsubscribe kernel-janitors" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html >
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. regards, dan carpenter
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 >
Sure, I'll resend. Unsigned is a little cleaner. There is no new error code/message or change in behavior though either way. regards, dan carpenter
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; } - if (adev->pp_enabled) { - struct pp_states_info data; - amdgpu_dpm_get_pp_num_states(adev, &data); - state = data.states[idx]; - /* only set user selected power states */ - if (state != POWER_STATE_TYPE_INTERNAL_BOOT && - state != POWER_STATE_TYPE_DEFAULT) { - amdgpu_dpm_dispatch_task(adev, - AMD_PP_EVENT_ENABLE_USER_STATE, &state, NULL); - adev->pp_force_state_enabled = true; - } + amdgpu_dpm_get_pp_num_states(adev, &data); + state = data.states[idx]; + /* only set user selected power states */ + if (state != POWER_STATE_TYPE_INTERNAL_BOOT && + state != POWER_STATE_TYPE_DEFAULT) { + amdgpu_dpm_dispatch_task(adev, + AMD_PP_EVENT_ENABLE_USER_STATE, &state, NULL); + adev->pp_force_state_enabled = true; } } fail:
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>