JBIG2Stream::readSymbolDictSeg: Return early if one of the bitmaps is null

Doesn't seem to regress any of the valid files i have and saves some
broken ones that loop for hours

1 files changed, 5 insertions, 1 deletions

diff --git a/poppler/JBIG2Stream.cc b/poppler/JBIG2Stream.cc
index 308bf772..db46b1ae 100644
--- a/poppler/JBIG2Stream.cc
+++ b/poppler/JBIG2Stream.cc
@@ -15,7 +15,7 @@
 //
 // Copyright (C) 2006 Raj Kumar <rkumar@archive.org>
 // Copyright (C) 2006 Paul Walmsley <paul@booyaka.com>
-// Copyright (C) 2006-2010, 2012, 2014-2020 Albert Astals Cid <aacid@kde.org>
+// Copyright (C) 2006-2010, 2012, 2014-2021 Albert Astals Cid <aacid@kde.org>
 // Copyright (C) 2009 David Benjamin <davidben@mit.edu>
 // Copyright (C) 2011 Edward Jiang <ejiang@google.com>
 // Copyright (C) 2012 William Bader <williambader@hotmail.com>
@@ -1756,6 +1756,10 @@ bool JBIG2Stream::readSymbolDictSeg(unsigned int segNum, unsigned int length, un
                 // non-ref/agg coding
             } else {
                 bitmaps[numInputSyms + i] = readGenericBitmap(false, symWidth, symHeight, sdTemplate, false, false, nullptr, sdATX, sdATY, 0).release();
+                if (unlikely(!bitmaps[numInputSyms + i])) {
+                    error(errSyntaxError, curStr->getPos(), "NULL bitmap in readGenericBitmap");
+                    goto syntaxError;
+                }
             }
 
             ++i;