From: Zack Rusin zackr@vmware.com

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@vmware.com Fixes: 2ac863719e51 ("vmwgfx: Snoop DMA transfers with non-covering sizes") Cc: stable@vger.kernel.org # v3.2+ Reviewed-by: Michael Banack banackm@vmware.com Reviewed-by: Martin Krastev krastevm@vmware.com --- 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 */