clones/php-src
1
0
Fork 0
mirror of https://github.com/php/php-src.git synced 2024-09-22 02:17:32 +00:00
Code Issues Packages Projects Releases Wiki Activity

Fix #77270: imagecolormatch Out Of Bounds Write on Heap

Browse Source 
At least some of the image reading functions may return images which
use color indexes greater than or equal to im->colorsTotal.  We cater
to this by always using a buffer size which is sufficient for
`gdMaxColors` in `gdImageColorMatch()`.
This commit is contained in:
Christoph M. Becker 2018-12-30 13:59:26 +01:00 committed by Stanislav Malyshev
parent 4feb9e66ff
commit 567c9f5842
2 changed files with 20 additions and 2 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

4
ext/gd/libgd/gd_color.c
View File

@ -33,8 +33,8 @@ int gdImageColorMatch (gdImagePtr im1, gdImagePtr im2)
return -4; /* At least 1 color must be allocated */
}
buf = (unsigned long *)safe_emalloc(sizeof(unsigned long), 5 * im2->colorsTotal, 0);
memset( buf, 0, sizeof(unsigned long) * 5 * im2->colorsTotal );
buf = (unsigned long *)safe_emalloc(sizeof(unsigned long), 5 * gdMaxColors, 0);
memset( buf, 0, sizeof(unsigned long) * 5 * gdMaxColors );
for (x=0; x<im1->sx; x++) {
for( y=0; y<im1->sy; y++ ) {

18
ext/gd/tests/bug77270.phpt Normal file
View File

@ -0,0 +1,18 @@
--TEST--
Bug #77270 (imagecolormatch Out Of Bounds Write on Heap)
--SKIPIF--
<?php
if (!extension_loaded('gd')) die('skip gd extension not available');
if (!GD_BUNDLED && version_compare(GD_VERSION, '2.2.5', '<=')) die('skip upstream bugfix has not been released');
?>
--FILE--
<?php
$img1 = imagecreatetruecolor(0xfff, 0xfff);
$img2 = imagecreate(0xfff, 0xfff);
imagecolorallocate($img2, 0, 0, 0);
imagesetpixel($img2, 0, 0, 255);
imagecolormatch($img1, $img2);
?>
===DONE===
--EXPECT--
===DONE===