vmware_vga: Check cursor dimensions passed from guest to avoid buffer overflow
Check that the cursor dimensions passed from the guest for the
DEFINE_CURSOR command don't overflow the available space in the
cursor.image[] or cursor.mask[] arrays before copying data from the
guest into those arrays.
Signed-off-by: Roland Dreier <rolandd@cisco.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
diff --git a/hw/vmware_vga.c b/hw/vmware_vga.c
index cdc1a05..e709369 100644
--- a/hw/vmware_vga.c
+++ b/hw/vmware_vga.c
@@ -562,6 +562,13 @@
cursor.height = y = vmsvga_fifo_read(s);
vmsvga_fifo_read(s);
cursor.bpp = vmsvga_fifo_read(s);
+
+ if (SVGA_BITMAP_SIZE(x, y) > sizeof cursor.mask ||
+ SVGA_PIXMAP_SIZE(x, y, cursor.bpp) > sizeof cursor.image) {
+ args = SVGA_BITMAP_SIZE(x, y) + SVGA_PIXMAP_SIZE(x, y, cursor.bpp);
+ goto badcmd;
+ }
+
for (args = 0; args < SVGA_BITMAP_SIZE(x, y); args ++)
cursor.mask[args] = vmsvga_fifo_read_raw(s);
for (args = 0; args < SVGA_PIXMAP_SIZE(x, y, cursor.bpp); args ++)
