From: Zack Rusin <zackr@xxxxxxxxxx>
commit 4cf949c7fafe21e085a4ee386bb2dade9067316e upstream.
Invalid userspace dma surface copies could potentially overflow
the memcpy from the surface to the snooped image leading to crashes.
To fix it the dimensions of the copybox have to be validated
against the expected size of the snooped cursor.
Signed-off-by: Zack Rusin <zackr@xxxxxxxxxx>
Fixes: 2ac863719e51 ("vmwgfx: Snoop DMA transfers with non-covering sizes")
Cc: <stable@xxxxxxxxxxxxxxx> # v3.2+
Reviewed-by: Michael Banack <banackm@xxxxxxxxxx>
Reviewed-by: Martin Krastev <krastevm@xxxxxxxxxx>
Link: https://patchwork.freedesktop.org/patch/msgid/20221026031936.1004280-1-zack@xxxxxxx
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/gpu/drm/vmwgfx/vmwgfx_kms.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)
--- a/drivers/gpu/drm/vmwgfx/vmwgfx_kms.c
+++ b/drivers/gpu/drm/vmwgfx/vmwgfx_kms.c
@@ -182,7 +182,8 @@ void vmw_kms_cursor_snoop(struct vmw_sur
if (cmd->dma.guest.ptr.offset % PAGE_SIZE ||
box->x != 0 || box->y != 0 || box->z != 0 ||
box->srcx != 0 || box->srcy != 0 || box->srcz != 0 ||
- box->d != 1 || box_count != 1) {
+ box->d != 1 || box_count != 1 ||
+ box->w > 64 || box->h > 64) {
/* TODO handle none page aligned offsets */
/* TODO handle more dst & src != 0 */
/* TODO handle more then one copy */
