From: Rene Gassmoeller <rene.gassmoeller@mailbox.org>
Date: Thu, 19 Jul 2018 00:42:35 +0000 (-0700)
Subject: Avoid out of bounds memory access
X-Git-Tag: v9.1.0-rc1~907^2~2
X-Git-Url: https://gitweb.dealii.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=0f57a0584d2146f001cec2e4df702458909f2d55;p=dealii.git

Avoid out of bounds memory access
---

diff --git a/source/base/data_out_base.cc b/source/base/data_out_base.cc
index a6f1f86197..ebb4f197cb 100644
--- a/source/base/data_out_base.cc
+++ b/source/base/data_out_base.cc
@@ -401,6 +401,10 @@ namespace DataOutBase
       const std::vector<Patch<dim, spacedim>> &patches,
       Table<2, Number> &                       data_vectors)
     {
+      // If there is nothing to write, just return
+      if (patches.size() == 0)
+        return;
+
       // unlike in the main function, we don't have here the data_names field,
       // so we initialize it with the number of data sets in the first patch.
       // the equivalence of these two definitions is checked in the main
@@ -7594,6 +7598,9 @@ DataOutBase::write_filtered_data(
   // no cells it actually owns, and in that case it is legit if there are no
   // patches
   Assert(patches.size() > 0, ExcNoPatches());
+#else
+  if (patches.size() == 0)
+	  return;
 #endif
 
   compute_sizes<dim, spacedim>(patches, n_node, n_cell);