On Thu, Mar 01, 2018 at 06:43:21PM +0530, Sharma, Shashank wrote:
> Regards
>
> Shashank
>
>
> On 2/24/2018 12:55 AM, Ville Syrjala wrote:
> > From: Ville Syrjälä <ville.syrjala@xxxxxxxxxxxxxxx>
> >
> > While we want to potentially support multiple different gamma/degamma
> > LUT sizes we can (and should) at least check that the blob length
> > is a multiple of the LUT entry size.
> I dint understand the exact idea behind doing this, how is this going to
> benefit ? May be a bit more description ?
The benefit is rejecting garbage fed in from userspace.
> >
> > Signed-off-by: Ville Syrjälä <ville.syrjala@xxxxxxxxxxxxxxx>
> > ---
> > drivers/gpu/drm/drm_atomic.c | 15 +++++++++++----
> > 1 file changed, 11 insertions(+), 4 deletions(-)
> >
> > diff --git a/drivers/gpu/drm/drm_atomic.c b/drivers/gpu/drm/drm_atomic.c
> > index 8945357212ba..933edec0299d 100644
> > --- a/drivers/gpu/drm/drm_atomic.c
> > +++ b/drivers/gpu/drm/drm_atomic.c
> > @@ -413,6 +413,7 @@ drm_atomic_replace_property_blob_from_id(struct drm_device *dev,
> > struct drm_property_blob **blob,
> > uint64_t blob_id,
> > ssize_t expected_size,
> > + ssize_t expected_size_mod,
> > bool *replaced)
> > {
> > struct drm_property_blob *new_blob = NULL;
> > @@ -422,7 +423,13 @@ drm_atomic_replace_property_blob_from_id(struct drm_device *dev,
> > if (new_blob == NULL)
> > return -EINVAL;
> >
> > - if (expected_size > 0 && expected_size != new_blob->length) {
> > + if (expected_size > 0 &&
> > + new_blob->length != expected_size) {
> > + drm_property_blob_put(new_blob);
> > + return -EINVAL;
> > + }
> One line needed here, matching the previous if() pattern
What line? Don't understand.
> > + if (expected_size_mod > 0 &&
> > + new_blob->length % expected_size_mod != 0) {
> > drm_property_blob_put(new_blob);
> > return -EINVAL;
> > }
> > @@ -470,7 +477,7 @@ int drm_atomic_crtc_set_property(struct drm_crtc *crtc,
> > ret = drm_atomic_replace_property_blob_from_id(dev,
> > &state->degamma_lut,
> > val,
> > - -1,
> > + -1, sizeof(struct drm_color_lut),
> > &replaced);
> > state->color_mgmt_changed |= replaced;
> > return ret;
> > @@ -478,7 +485,7 @@ int drm_atomic_crtc_set_property(struct drm_crtc *crtc,
> > ret = drm_atomic_replace_property_blob_from_id(dev,
> > &state->ctm,
> > val,
> > - sizeof(struct drm_color_ctm),
> > + sizeof(struct drm_color_ctm), -1,
> > &replaced);
> > state->color_mgmt_changed |= replaced;
> > return ret;
> > @@ -486,7 +493,7 @@ int drm_atomic_crtc_set_property(struct drm_crtc *crtc,
> > ret = drm_atomic_replace_property_blob_from_id(dev,
> > &state->gamma_lut,
> > val,
> > - -1,
> > + -1, sizeof(struct drm_color_lut),
> > &replaced);
> > state->color_mgmt_changed |= replaced;
> > return ret;
--
Ville Syrjälä
Intel OTC
_______________________________________________
dri-devel mailing list
dri-devel@xxxxxxxxxxxxxxxxxxxxx
https://lists.freedesktop.org/mailman/listinfo/dri-devel
