From 94b283341f9f3f0ed56a360533766377a01540e0 Mon Sep 17 00:00:00 2001 From: Zack Rusin Date: Tue, 25 Oct 2022 23:19:35 -0400 Subject: [PATCH] drm/vmwgfx: Validate the box size for the snooped cursor 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 Fixes: 2ac863719e51 ("vmwgfx: Snoop DMA transfers with non-covering sizes") Cc: # v3.2+ Reviewed-by: Michael Banack Reviewed-by: Martin Krastev Link: https://patchwork.freedesktop.org/patch/msgid/20221026031936.1004280-1-zack@kde.org Signed-off-by: Greg Kroah-Hartman --- drivers/gpu/drm/vmwgfx/vmwgfx_kms.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/drivers/gpu/drm/vmwgfx/vmwgfx_kms.c b/drivers/gpu/drm/vmwgfx/vmwgfx_kms.c index 0b800c3540492..2492d3a19f36c 100644 --- 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_surface *srf, 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 */