The commit e133e737 didn't correctly fix the overflow issue.
- unsigned int required_size; + u64 required_size; ... required_size = mode_cmd->pitch * mode_cmd->height; - if (unlikely(required_size > dev_priv->vram_size)) { + if (unlikely(required_size > (u64) dev_priv->vram_size)) {
Since pitch and height are u32, their product is still 32-bit and would overflow. Converting the result to u64 cannot help. A correct way is to convert pitch and height to u64 before the multiplication.
required_size = (u64)mode_cmd->pitch * (u64)mode_cmd->height;
This fix calls vmw_kms_validate_mode_vram() for validation.
Signed-off-by: Xi Wang xi.wang@gmail.com Cc: Thomas Hellstrom thellstrom@vmware.com Cc: Dave Airlie airlied@redhat.com --- drivers/gpu/drm/vmwgfx/vmwgfx_kms.c | 6 +++--- 1 files changed, 3 insertions(+), 3 deletions(-)
diff --git a/drivers/gpu/drm/vmwgfx/vmwgfx_kms.c b/drivers/gpu/drm/vmwgfx/vmwgfx_kms.c index 37d4054..582a4d7 100644 --- a/drivers/gpu/drm/vmwgfx/vmwgfx_kms.c +++ b/drivers/gpu/drm/vmwgfx/vmwgfx_kms.c @@ -1003,7 +1003,6 @@ static struct drm_framebuffer *vmw_kms_fb_create(struct drm_device *dev, struct vmw_surface *surface = NULL; struct vmw_dma_buffer *bo = NULL; struct ttm_base_object *user_obj; - u64 required_size; int ret;
/** @@ -1012,8 +1011,9 @@ static struct drm_framebuffer *vmw_kms_fb_create(struct drm_device *dev, * requested framebuffer. */
- required_size = mode_cmd->pitch * mode_cmd->height; - if (unlikely(required_size > (u64) dev_priv->vram_size)) { + if (!vmw_kms_validate_mode_vram(dev_priv, + mode_cmd->pitch, + mode_cmd->height)) { DRM_ERROR("VRAM size is too small for requested mode.\n"); return ERR_PTR(-ENOMEM); }