From: Jean-Marc Lasgouttes <lasgouttes@lyx.org>
Date: Tue, 28 Mar 2017 09:17:35 +0000 (+0200)
Subject: Limit the amount of derivatives in external CAS
X-Git-Tag: 2.3.0alpha1~161
X-Git-Url: https://git.lyx.org/gitweb/?a=commitdiff_plain;h=bc7704a78e32e67253847fdd3d163005fa615209;p=features.git

Limit the amount of derivatives in external CAS

The (arbitrary) limit is 1000.

Pointed out by coverity. A bad value could lock LyX.
---

diff --git a/src/mathed/MathExtern.cpp b/src/mathed/MathExtern.cpp
index ee2004b508..da43bd4e35 100644
--- a/src/mathed/MathExtern.cpp
+++ b/src/mathed/MathExtern.cpp
@@ -896,6 +896,10 @@ void extractDiff(MathData & ar)
 				int mult = 1;
 				if (extractNumber(script->up(), mult)) {
 					//lyxerr << "mult: " << mult << endl;
+					if (mult > 1000) {
+						lyxerr << "Cannot differentiate more than 1000 times !" << endl;
+						continue;
+					}
 					for (int i = 0; i < mult; ++i)
 						diff->addDer(MathData(buf, dt + 1, st));
 				}