drm/amdgpu: validate user pitch alignment

Userspace may request pitch alignment that is not supported by GPU.
Some requests 32, but GPU ignores it and uses default 64 when cpp is
4. If GEM object is allocated based on the smaller alignment, GPU
DMA will go out of bound.

Cc: stable@vger.kernel.org # v4.2+
Reviewed-by: Michel Dänzer <michel.daenzer@amd.com>
Signed-off-by: Yu Zhao <yuzhao@google.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
This commit is contained in:
Yu Zhao 2019-01-07 15:51:14 -07:00 committed by Alex Deucher
parent fadcb8f9fc
commit 89f23b6efe
1 changed files with 10 additions and 0 deletions

View File

@ -531,6 +531,16 @@ amdgpu_display_user_framebuffer_create(struct drm_device *dev,
struct drm_gem_object *obj;
struct amdgpu_framebuffer *amdgpu_fb;
int ret;
struct amdgpu_device *adev = dev->dev_private;
int cpp = drm_format_plane_cpp(mode_cmd->pixel_format, 0);
int pitch = mode_cmd->pitches[0] / cpp;
pitch = amdgpu_align_pitch(adev, pitch, cpp, false);
if (mode_cmd->pitches[0] != pitch) {
DRM_DEBUG_KMS("Invalid pitch: expecting %d but got %d\n",
pitch, mode_cmd->pitches[0]);
return ERR_PTR(-EINVAL);
}
obj = drm_gem_object_lookup(file_priv, mode_cmd->handles[0]);
if (obj == NULL) {