[poppler] poppler/GfxState.cc

[Albert Astals Cid]

 poppler/GfxState.cc |   20 ++++++++++++++++----
 1 file changed, 16 insertions(+), 4 deletions(-)

New commits:
commit 6169bfb1ecd289a8235be0b8884a550f5d1ad926
Author: Albert Astals Cid <aacid at kde.org>
Date:   Tue May 22 19:56:34 2018 +0200

    GfxState.cc: Fix potential division by zero
    
    fixes oss-fuzz/8465

diff --git a/poppler/GfxState.cc b/poppler/GfxState.cc
index 5d7cc6ba..97c6d0d1 100644
--- a/poppler/GfxState.cc
+++ b/poppler/GfxState.cc
@@ -72,9 +72,13 @@
 
 GBool Matrix::invertTo(Matrix *other) const
 {
-  double det;
+  const double det_denominator = determinant();
+  if (unlikely(det_denominator == 0)) {
+      *other = {1, 0, 0, 1, 0, 0};
+      return gFalse;
+  }
 
-  det = 1 / determinant();
+  const double det = 1 / det_denominator;
   other->m[0] = m[3] * det;
   other->m[1] = -m[1] * det;
   other->m[2] = -m[2] * det;
@@ -6745,10 +6749,18 @@ void GfxState::setPath(GfxPath *pathA) {
 void GfxState::getUserClipBBox(double *xMin, double *yMin,
 			       double *xMax, double *yMax) {
   double ictm[6];
-  double xMin1, yMin1, xMax1, yMax1, det, tx, ty;
+  double xMin1, yMin1, xMax1, yMax1, tx, ty;
 
   // invert the CTM
-  det = 1 / (ctm[0] * ctm[3] - ctm[1] * ctm[2]);
+  const double det_denominator = (ctm[0] * ctm[3] - ctm[1] * ctm[2]);
+  if (unlikely(det_denominator == 0)) {
+      *xMin = 0;
+      *yMin = 0;
+      *xMax = 0;
+      *yMax = 0;
+      return;
+  }
+  const double det = 1 / det_denominator;
   ictm[0] = ctm[3] * det;
   ictm[1] = -ctm[1] * det;
   ictm[2] = -ctm[2] * det;