cjpeg: Fix FPE when compressing 0-width GIF
Fixes #493
diff --git a/ChangeLog.md b/ChangeLog.md
index 92bf27e..61a9095 100644
--- a/ChangeLog.md
+++ b/ChangeLog.md
@@ -15,6 +15,10 @@
encoders to generate incorrect results when using the Clang compiler with
Visual Studio.
+4. Fixed a floating point exception that occurred when attempting to compress a
+specially-crafted malformed GIF image with a specified image width of 0 using
+cjpeg.
+
2.0.90 (2.1 beta1)
==================
diff --git a/cderror.h b/cderror.h
index a386b69..2844346 100644
--- a/cderror.h
+++ b/cderror.h
@@ -1,9 +1,11 @@
/*
* cderror.h
*
+ * This file was part of the Independent JPEG Group's software:
* Copyright (C) 1994-1997, Thomas G. Lane.
* Modified 2009-2017 by Guido Vollbeding.
- * This file is part of the Independent JPEG Group's software.
+ * libjpeg-turbo Modifications:
+ * Copyright (C) 2021, D. R. Commander.
* For conditions of distribution and use, see the accompanying README.ijg
* file.
*
@@ -60,6 +62,7 @@
JMESSAGE(JERR_GIF_BUG, "GIF output got confused")
JMESSAGE(JERR_GIF_CODESIZE, "Bogus GIF codesize %d")
JMESSAGE(JERR_GIF_COLORSPACE, "GIF output must be grayscale or RGB")
+JMESSAGE(JERR_GIF_EMPTY, "Empty GIF image")
JMESSAGE(JERR_GIF_IMAGENOTFOUND, "Too few images in GIF file")
JMESSAGE(JERR_GIF_NOT, "Not a GIF file")
JMESSAGE(JTRC_GIF, "%ux%ux%d GIF image")
diff --git a/rdgif.c b/rdgif.c
index e1ea56c..8a379fe 100644
--- a/rdgif.c
+++ b/rdgif.c
@@ -1,9 +1,11 @@
/*
* rdgif.c
*
+ * This file was part of the Independent JPEG Group's software:
* Copyright (C) 1991-1997, Thomas G. Lane.
* Modified 2019 by Guido Vollbeding.
- * This file is part of the Independent JPEG Group's software.
+ * libjpeg-turbo Modifications:
+ * Copyright (C) 2021, D. R. Commander.
* For conditions of distribution and use, see the accompanying README.ijg
* file.
*
@@ -404,6 +406,8 @@
ERREXIT(cinfo, JERR_INPUT_EOF);
width = LM_to_uint(hdrbuf, 0);
height = LM_to_uint(hdrbuf, 2);
+ if (width == 0 || height == 0)
+ ERREXIT(cinfo, JERR_GIF_EMPTY);
/* we ignore the color resolution, sort flag, and background color index */
aspectRatio = UCH(hdrbuf[6]);
if (aspectRatio != 0 && aspectRatio != 49)
@@ -446,6 +450,8 @@
/* we ignore top/left position info, also sort flag */
width = LM_to_uint(hdrbuf, 4);
height = LM_to_uint(hdrbuf, 6);
+ if (width == 0 || height == 0)
+ ERREXIT(cinfo, JERR_GIF_EMPTY);
source->is_interlaced = (BitSet(hdrbuf[8], INTERLACE) != 0);
/* Read local colormap if header indicates it is present */
