This patch fixes a possible kernel crash when drm_unlock (DRM_IOCTL_UNLOCK) is called by a application that has not had a lock created by it. This crash can be caused by any application from all users.
Issue: VIZ-5485 Signed-off-by: Peter Antoine peter.antoine@intel.com --- drivers/gpu/drm/drm_lock.c | 8 ++++++++ 1 file changed, 8 insertions(+)
diff --git a/drivers/gpu/drm/drm_lock.c b/drivers/gpu/drm/drm_lock.c index f861361..070dd5d 100644 --- a/drivers/gpu/drm/drm_lock.c +++ b/drivers/gpu/drm/drm_lock.c @@ -159,6 +159,14 @@ int drm_legacy_unlock(struct drm_device *dev, void *data, struct drm_file *file_ return -EINVAL; }
+ if (!master->lock.hw_lock) { + DRM_ERROR( + "Device has been unregistered. Hard exit. Process %d\n", + task_pid_nr(current)); + send_sig(SIGTERM, current, 0); + return -EPERM; + } + if (drm_legacy_lock_free(&master->lock, lock->context)) { /* FIXME: Should really bail out here. */ }