summaryrefslogtreecommitdiff
diff options
context:
space:
mode:
authorChristoph M. Becker <cmbecker69@gmx.de>2018-12-30 13:59:26 +0100
committerChristoph M. Becker <cmbecker69@gmx.de>2019-01-07 13:41:51 +0100
commita15af81b5f0058e020eda0f109f51a3c863f5212 (patch)
tree51f93265d490535cc8056ccd2e6347ae78f3f784
parent027f68ff10a439c5c331bcbfdd6eb2a5fca0948a (diff)
downloadphp-git-a15af81b5f0058e020eda0f109f51a3c863f5212.tar.gz
Fix #77270: imagecolormatch Out Of Bounds Write on Heap
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()`. (cherry picked from commit 7a12dad4dd6c370835b13afae214b240082c7538)
-rw-r--r--NEWS1
-rw-r--r--ext/gd/libgd/gd_color_match.c4
-rw-r--r--ext/gd/tests/bug77270.phpt18
3 files changed, 21 insertions, 2 deletions
diff --git a/NEWS b/NEWS
index d208a7dc3b..4ece82c45a 100644
--- a/NEWS
+++ b/NEWS
@@ -29,6 +29,7 @@ PHP NEWS
(cmb)
. Fixed bug #77269 (efree() on uninitialized Heap data in imagescale leads to
use-after-free). (cmb)
+ . Fixed bug #77270 (imagecolormatch Out Of Bounds Write on Heap). (cmb)
- OCI8:
. Fixed bug #76804 (oci_pconnect with OCI_CRED_EXT not working). (KoenigsKind)
diff --git a/ext/gd/libgd/gd_color_match.c b/ext/gd/libgd/gd_color_match.c
index a4e56b1c40..e6f539bc75 100644
--- a/ext/gd/libgd/gd_color_match.c
+++ b/ext/gd/libgd/gd_color_match.c
@@ -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++ ) {
diff --git a/ext/gd/tests/bug77270.phpt b/ext/gd/tests/bug77270.phpt
new file mode 100644
index 0000000000..1c4555a64d
--- /dev/null
+++ b/ext/gd/tests/bug77270.phpt
@@ -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===