cirrus: Fix host CPU blits
commitd16136d22af0fcf0d651de04c9e3cbc7137cc6f9
authorBenjamin Herrenschmidt <benh@kernel.crashing.org>
Mon, 7 Jul 2014 00:32:34 +0000 (7 10:32 +1000)
committerGerd Hoffmann <kraxel@redhat.com>
Fri, 11 Jul 2014 08:17:02 +0000 (11 10:17 +0200)
treeb667e257de01f24e77031f64ca21f5c31b414bd5
parente8ee4b68bed36471b014c23209299c84b8d4a01b
cirrus: Fix host CPU blits

Commit b2eb849d4b1fdb6f35d5c46958c7f703cf64cfef
"CVE-2007-1320 - Cirrus LGD-54XX "bitblt" heap overflow" broke
cpu to video blits.

When the ROP function is called from cirrus_bitblt_cputovideo_next(),
we pass 0 for the pitch but only operate on one line at a time. The
added test was tripping because after the initial substraction, the
pitch becomes negative. Make the test only trip when the height is
larger than one (ie. the pitch is actually used).

This fixes HW cursor support in Windows NT4.0 (which otherwise was
a white rectangle) and general display of icons in that OS when using
8bpp mode.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
hw/display/cirrus_vga_rop.h