vnc: Fix tight_detect_smooth_image() for lossless case

VncTight member uint8_t quality is either (uint8_t)-1 for lossless or
less than 10 for lossy.

tight_detect_smooth_image() first promotes it to int, then compares
with -1.  Always unequal, so we always execute the lossy code.  Reads
beyond tight_conf[] and returns crap when quality is actually
lossless.

Compare to (uint8_t)-1 instead, like we do elsewhere.

Spotted by Coverity.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
This commit is contained in:
Markus Armbruster 2014-02-21 16:42:52 +01:00 committed by Gerd Hoffmann
parent f53f3d0a00
commit 2e7bcdb99a

View File

@ -330,7 +330,7 @@ tight_detect_smooth_image(VncState *vs, int w, int h)
} else {
errors = tight_detect_smooth_image16(vs, w, h);
}
if (quality != -1) {
if (quality != (uint8_t)-1) {
return (errors < tight_conf[quality].jpeg_threshold);
}
return (errors < tight_conf[compression].gradient_threshold);