etnaviv: fix gem object list corruption

All manipulations of the gem_object list need to be protected by
the list mutex, as GEM objects can be created and freed in parallel.
This fixes a kernel memory corruption.

CC: stable@vger.kernel.org
Signed-off-by: Lucas Stach <l.stach@pengutronix.de>

1 files changed, 3 insertions, 0 deletions

diff --git a/drivers/gpu/drm/etnaviv/etnaviv_gem.c b/drivers/gpu/drm/etnaviv/etnaviv_gem.c
index 9a3bea738330..87b95eeedd9e 100644
--- a/drivers/gpu/drm/etnaviv/etnaviv_gem.c
+++ b/drivers/gpu/drm/etnaviv/etnaviv_gem.c
@@ -551,12 +551,15 @@ static const struct etnaviv_gem_ops etnaviv_gem_shmem_ops = {
 void etnaviv_gem_free_object(struct drm_gem_object *obj)
 {
         struct etnaviv_gem_object *etnaviv_obj = to_etnaviv_bo(obj);
+        struct etnaviv_drm_private *priv = obj->dev->dev_private;
         struct etnaviv_vram_mapping *mapping, *tmp;
 
         /* object should not be active */
         WARN_ON(is_active(etnaviv_obj));
 
+        mutex_lock(&priv->gem_lock);
         list_del(&etnaviv_obj->gem_node);
+        mutex_unlock(&priv->gem_lock);
 
         list_for_each_entry_safe(mapping, tmp, &etnaviv_obj->vram_list,
                                  obj_node) {