From 6bb9d7ea3fdc22a8a03b989e430d0f4953e59f03 Mon Sep 17 00:00:00 2001
From: DRC <information@libjpeg-turbo.org>
Date: Thu, 14 Jan 2021 18:35:15 -0600
Subject: [PATCH] cjpeg: Fix FPE when compressing 0-width GIF

---
 cderror.h | 5 ++++-
 rdgif.c   | 8 +++++++-
 2 files changed, 11 insertions(+), 2 deletions(-)

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(JTRC_BMP_OS2_MAPPED, "%ux%u 8-bit colormapped OS2 BMP image")
 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 @@ start_input_gif(j_compress_ptr cinfo, cjpeg_source_ptr sinfo)
     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 @@ start_input_gif(j_compress_ptr cinfo, cjpeg_source_ptr sinfo)
     /* 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 */
-- 
2.26.3