0023-Don-t-crash-on-broken-GIF-images.patch

   1 From f1b76c126c476c155af8c404b97c42cd1a709333 Mon Sep 17 00:00:00 2001
   2 From: Lars Knoll <lars.knoll@digia.com>
   3 Date: Thu, 24 Apr 2014 15:33:27 +0200
   4 Subject: [PATCH 23/74] Don't crash on broken GIF images
   5
   6 Broken GIF images could set invalid width and height
   7 values inside the image, leading to Qt creating a null
   8 QImage for it. In that case we need to abort decoding
   9 the image and return an error.
  10
  11 Initial patch by Rich Moore.
  12
  13 Backport of Id82a4036f478bd6e49c402d6598f57e7e5bb5e1e from Qt 5
  14
  15 Task-number: QTBUG-38367
  16 Change-Id: I0680740018aaa8356d267b7af3f01fac3697312a
  17 Security-advisory: CVE-2014-0190
  18 Reviewed-by: Richard J. Moore <rich@kde.org>
  19 ---
  20  src/gui/image/qgifhandler.cpp | 7 +++++++
  21  1 file changed, 7 insertions(+)
  22
  23 diff --git a/src/gui/image/qgifhandler.cpp b/src/gui/image/qgifhandler.cpp
  24 index 3324f04..5199dd3 100644
  25 --- a/src/gui/image/qgifhandler.cpp
  26 +++ b/src/gui/image/qgifhandler.cpp
  27 @@ -359,6 +359,13 @@ int QGIFFormat::decode(QImage *image, const uchar *buffer, int length,
  28                      memset(bits, 0, image->byteCount());
  29                  }
  30
  31 +                // Check if the previous attempt to create the image failed. If it
  32 +                // did then the image is broken and we should give up.
  33 +                if (image->isNull()) {
  34 +                    state = Error;
  35 +                    return -1;
  36 +                }
  37 +
  38                  disposePrevious(image);
  39                  disposed = false;
  40
  41 --
  42 1.9.3
  43