Commit 982b173a authored by Min Li's avatar Min Li Committed by Alex Deucher
Browse files

drm/radeon: fix race condition UAF in radeon_gem_set_domain_ioctl 



Userspace can race to free the gobj(robj converted from), robj should not
be accessed again after drm_gem_object_put, otherwith it will result in
use-after-free.

Reviewed-by: default avatarChristian König <christian.koenig@amd.com>
Signed-off-by: default avatarMin Li <lm0963hack@gmail.com>
Signed-off-by: default avatarAlex Deucher <alexander.deucher@amd.com>
parent 73c12de8

drivers/gpu/drm/radeon/radeon_gem.c

+1 −3
Original line number Diff line number Diff line
@@ -459,7 +459,6 @@ int radeon_gem_set_domain_ioctl(struct drm_device *dev, void *data, 
	struct radeon_device *rdev = dev->dev_private;

	struct drm_radeon_gem_set_domain *args = data;

	struct drm_gem_object *gobj;

	struct radeon_bo *robj;

	int r;



	/* for now if someone requests domain CPU -
@@ -472,13 +471,12 @@ int radeon_gem_set_domain_ioctl(struct drm_device *dev, void *data, 
		up_read(&rdev->exclusive_lock);

		return -ENOENT;

	}

	robj = gem_to_radeon_bo(gobj);



	r = radeon_gem_set_domain(gobj, args->read_domains, args->write_domain);



	drm_gem_object_put(gobj);

	up_read(&rdev->exclusive_lock);

	r = radeon_gem_handle_lockup(robj->rdev, r);

	r = radeon_gem_handle_lockup(rdev, r);

	return r;

}