From 30b8a98a1ab30d3622d2fa34794dd3ef0e01eca2 Mon Sep 17 00:00:00 2001 From: Tina Zhang Date: Tue, 25 Feb 2020 13:35:27 +0800 Subject: [PATCH] drm/i915/gvt: Fix orphan vgpu dmabuf_objs' lifetime 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 Reviewed-by: Zhenyu Wang Signed-off-by: Zhenyu Wang Link: http://patchwork.freedesktop.org/patch/msgid/20200225053527.8336-2-tina.zhang@intel.com Signed-off-by: Greg Kroah-Hartman --- 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 4bfaefdf548d..c0347956f7cf 100644 --- a/drivers/gpu/drm/i915/gvt/dmabuf.c +++ b/drivers/gpu/drm/i915/gvt/dmabuf.c @@ -96,12 +96,12 @@ 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; } }