From 4cf949c7fafe21e085a4ee386bb2dade9067316e 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 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 --- 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 0342efdf9063..d434b6ae1092 100644 --- a/drivers/gpu/drm/vmwgfx/vmwgfx_kms.c +++ b/drivers/gpu/drm/vmwgfx/vmwgfx_kms.c @@ -393,7 +393,8 @@ 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 */