Fix a crash due to missing zero-bytes check

Resolves: #1767921

djvulibre-3.5.27-zero-bytes-check.patch

@@ -0,0 +1,28 @@
+From 9658b01431cd7ff6344d7787f855179e73fe81a7 Mon Sep 17 00:00:00 2001
+From: Leon Bottou <leon@bottou.org>
+Date: Mon, 8 Apr 2019 22:55:38 -0400
+Subject: fix bug #298
+
+
+diff --git a/libdjvu/GBitmap.h b/libdjvu/GBitmap.h
+index e8e0c9b..ca89a19 100644
+--- a/libdjvu/GBitmap.h
++++ b/libdjvu/GBitmap.h
+@@ -566,7 +566,7 @@ GBitmap::operator[](int row)
+ {
+   if (!bytes) 
+     uncompress();
+-  if (row<0 || row>=nrows) {
++  if (row<0 || row>=nrows || !bytes) {
+ #ifndef NDEBUG
+     if (zerosize < bytes_per_row + border)
+       G_THROW( ERR_MSG("GBitmap.zero_small") );
+@@ -581,7 +581,7 @@ GBitmap::operator[](int row) const
+ {
+   if (!bytes) 
+     ((GBitmap*)this)->uncompress();
+-  if (row<0 || row>=nrows) {
++  if (row<0 || row>=nrows || !bytes) {
+ #ifndef NDEBUG
+     if (zerosize < bytes_per_row + border)
+       G_THROW( ERR_MSG("GBitmap.zero_small") );

djvulibre.spec

@@ -3,7 +3,7 @@
 Summary: DjVu viewers, encoders, and utilities
 Name: djvulibre
 Version: 3.5.27
-Release: 15%{?dist}
+Release: 16%{?dist}
 License: GPLv2+
 URL: http://djvu.sourceforge.net/
 Source0: http://downloads.sourceforge.net/djvu/%{name}-%{version}.tar.gz
@@ -12,6 +12,7 @@ Patch0: djvulibre-3.5.22-cdefs.patch
 Patch2: djvulibre-3.5.27-buffer-overflow.patch
 Patch3: djvulibre-3.5.27-infinite-loop.patch
 Patch4: djvulibre-3.5.27-stack-overflow.patch
+Patch5: djvulibre-3.5.27-zero-bytes-check.patch
 
 Requires(post): xdg-utils
 Requires(preun): xdg-utils
@@ -67,6 +68,7 @@ Development files for DjVuLibre.
 %patch2 -p1 -b .buffer-overflow
 %patch3 -p1 -b .infinite-loop
 %patch4 -p1 -b .stack-overflow
+%patch5 -p1 -b .zero-bytes-check
 
 
 %build 
@@ -174,6 +176,10 @@ fi
 
 
 %changelog
+* Thu Nov  7 2019 Marek Kasik <mkasik@redhat.com> - 3.5.27-16
+- Fix a crash due to missing zero-bytes check
+- Resolves: #1767921
+
 * Thu Nov  7 2019 Marek Kasik <mkasik@redhat.com> - 3.5.27-15
 - Fix a stack overflow
 - Resolves: #1767868