From: Tina Zhang tina.zhang@intel.com
commit b549c252b1292aea959cd9b83537fcb9384a6112 upstream.
Deleting dmabuf item's list head after releasing its container can lead to KASAN-reported issue:
BUG: KASAN: use-after-free in __list_del_entry_valid+0x15/0xf0 Read of size 8 at addr ffff88818a4598a8 by task kworker/u8:3/13119
So fix this issue by puting deleting dmabuf_objs ahead of releasing its container.
Fixes: dfb6ae4e14bd6 ("drm/i915/gvt: Handle orphan dmabuf_objs") Signed-off-by: Tina Zhang tina.zhang@intel.com Reviewed-by: Zhenyu Wang zhenyuw@linux.intel.com Signed-off-by: Zhenyu Wang zhenyuw@linux.intel.com Link: http://patchwork.freedesktop.org/patch/msgid/20200225053527.8336-2-tina.zhan... Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org Signed-off-by: Yang Yingliang yangyingliang@huawei.com --- drivers/gpu/drm/i915/gvt/dmabuf.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/gpu/drm/i915/gvt/dmabuf.c b/drivers/gpu/drm/i915/gvt/dmabuf.c index 51ed99a..6053f5a 100644 --- a/drivers/gpu/drm/i915/gvt/dmabuf.c +++ b/drivers/gpu/drm/i915/gvt/dmabuf.c @@ -95,12 +95,12 @@ static void dmabuf_gem_object_free(struct kref *kref) dmabuf_obj = container_of(pos, struct intel_vgpu_dmabuf_obj, list); if (dmabuf_obj == obj) { + list_del(pos); intel_gvt_hypervisor_put_vfio_device(vgpu); idr_remove(&vgpu->object_idr, dmabuf_obj->dmabuf_id); kfree(dmabuf_obj->info); kfree(dmabuf_obj); - list_del(pos); break; } }