4.11-stable review patch. If anyone has any objections, please let me know.
------------------
From: Sinclair Yeh <syeh@xxxxxxxxxx>
commit 07678eca2cf9c9a18584e546c2b2a0d0c9a3150c upstream.
When vmw_gb_surface_define_ioctl() is called with an existing buffer,
we end up returning an uninitialized variable in the backup_handle.
The fix is to first initialize backup_handle to 0 just to be sure, and
second, when a user-provided buffer is found, we will use the
req->buffer_handle as the backup_handle.
Reported-by: Murray McAllister <murray.mcallister@xxxxxxxxxxxxxxx>
Signed-off-by: Sinclair Yeh <syeh@xxxxxxxxxx>
Reviewed-by: Deepak Rawat <drawat@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/gpu/drm/vmwgfx/vmwgfx_surface.c | 18 +++++++++++-------
1 file changed, 11 insertions(+), 7 deletions(-)
--- a/drivers/gpu/drm/vmwgfx/vmwgfx_surface.c
+++ b/drivers/gpu/drm/vmwgfx/vmwgfx_surface.c
@@ -1275,7 +1275,7 @@ int vmw_gb_surface_define_ioctl(struct d
struct ttm_object_file *tfile = vmw_fpriv(file_priv)->tfile;
int ret;
uint32_t size;
- uint32_t backup_handle;
+ uint32_t backup_handle = 0;
if (req->multisample_count != 0)
return -EINVAL;
@@ -1318,12 +1318,16 @@ int vmw_gb_surface_define_ioctl(struct d
ret = vmw_user_dmabuf_lookup(tfile, req->buffer_handle,
&res->backup,
&user_srf->backup_base);
- if (ret == 0 && res->backup->base.num_pages * PAGE_SIZE <
- res->backup_size) {
- DRM_ERROR("Surface backup buffer is too small.\n");
- vmw_dmabuf_unreference(&res->backup);
- ret = -EINVAL;
- goto out_unlock;
+ if (ret == 0) {
+ if (res->backup->base.num_pages * PAGE_SIZE <
+ res->backup_size) {
+ DRM_ERROR("Surface backup buffer is too small.\n");
+ vmw_dmabuf_unreference(&res->backup);
+ ret = -EINVAL;
+ goto out_unlock;
+ } else {
+ backup_handle = req->buffer_handle;
+ }
}
} else if (req->drm_surface_flags & drm_vmw_surface_flag_create_buffer)
ret = vmw_user_dmabuf_alloc(dev_priv, tfile,