2019-05-11 06:14:04

by Murray McAllister

Subject: [PATCH] drm/vmwgfx: NULL pointer dereference from vmw_cmd_dx_view_define()

If SVGA_3D_CMD_DX_DEFINE_RENDERTARGET_VIEW is called with a surface
ID of SVGA3D_INVALID_ID, the srf struct will remain NULL after
vmw_cmd_res_check(), leading to a null pointer dereference in
vmw_view_add().

Signed-off-by: Murray McAllister <[email protected]>
---
drivers/gpu/drm/vmwgfx/vmwgfx_execbuf.c | 4 ++++
1 file changed, 4 insertions(+)

diff --git a/drivers/gpu/drm/vmwgfx/vmwgfx_execbuf.c b/drivers/gpu/drm/vmwgfx/vmwgfx_execbuf.c
index 2ff7ba04d8c8..447afd086206 100644
--- a/drivers/gpu/drm/vmwgfx/vmwgfx_execbuf.c
+++ b/drivers/gpu/drm/vmwgfx/vmwgfx_execbuf.c
@@ -2414,6 +2414,10 @@ static int vmw_cmd_dx_view_define(struct vmw_private *dev_priv,
return -EINVAL;

cmd = container_of(header, typeof(*cmd), header);
+ if (unlikely(cmd->sid == SVGA3D_INVALID_ID)) {
+ DRM_ERROR("Invalid surface id.\n");
+ return -EINVAL;
+ }
ret = vmw_cmd_res_check(dev_priv, sw_context, vmw_res_surface,
VMW_RES_DIRTY_NONE, user_surface_converter,
&cmd->sid, &srf);
--
2.20.1

2019-05-13 13:54:54

by Thomas Hellstrom

Subject: Re: [PATCH] drm/vmwgfx: NULL pointer dereference from vmw_cmd_dx_view_define()

On Sat, 2019-05-11 at 18:01 +1200, Murray McAllister wrote:
> If SVGA_3D_CMD_DX_DEFINE_RENDERTARGET_VIEW is called with a surface
> ID of SVGA3D_INVALID_ID, the srf struct will remain NULL after
> vmw_cmd_res_check(), leading to a null pointer dereference in
> vmw_view_add().
>
> Signed-off-by: Murray McAllister <[email protected]>

Thanks, I'll add this to the next -fixes pull.
Thomas


> ---
> drivers/gpu/drm/vmwgfx/vmwgfx_execbuf.c | 4 ++++
> 1 file changed, 4 insertions(+)
>
> diff --git a/drivers/gpu/drm/vmwgfx/vmwgfx_execbuf.c
> b/drivers/gpu/drm/vmwgfx/vmwgfx_execbuf.c
> index 2ff7ba04d8c8..447afd086206 100644
> --- a/drivers/gpu/drm/vmwgfx/vmwgfx_execbuf.c
> +++ b/drivers/gpu/drm/vmwgfx/vmwgfx_execbuf.c
> @@ -2414,6 +2414,10 @@ static int vmw_cmd_dx_view_define(struct
> vmw_private *dev_priv,
> return -EINVAL;
>
> cmd = container_of(header, typeof(*cmd), header);
> + if (unlikely(cmd->sid == SVGA3D_INVALID_ID)) {
> + DRM_ERROR("Invalid surface id.\n");
> + return -EINVAL;
> + }
> ret = vmw_cmd_res_check(dev_priv, sw_context, vmw_res_surface,
> VMW_RES_DIRTY_NONE,
> user_surface_converter,
> &cmd->sid, &srf);