3.16.46-rc1 review patch. If anyone has any objections, please let me know.
------------------ From: Sinclair Yeh <[email protected]> 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 <[email protected]> Signed-off-by: Sinclair Yeh <[email protected]> Reviewed-by: Deepak Rawat <[email protected]> [bwh: Backported to 3.16: There's no size check after vmw_user_dmabuf_lookup(), so only check ret == 0.] Signed-off-by: Ben Hutchings <[email protected]> --- --- a/drivers/gpu/drm/vmwgfx/vmwgfx_surface.c +++ b/drivers/gpu/drm/vmwgfx/vmwgfx_surface.c @@ -1245,7 +1245,7 @@ int vmw_gb_surface_define_ioctl(struct d int ret; uint32_t size; const struct svga3d_surface_desc *desc; - uint32_t backup_handle; + uint32_t backup_handle = 0; if (req->mip_levels > DRM_VMW_MAX_MIP_LEVELS) return -EINVAL; @@ -1317,6 +1317,8 @@ 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) + 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,
