From: Lenny Maiorani <lenny@colorado.edu>
Date: Thu, 28 Apr 2011 18:59:43 +0000 (+0000)
Subject: Eliminates an assert in the strncpy/strncat checker caused by not validating a cast... 
X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=508c627db67ea4b53439fbcd688145f24d9c0400;p=clang

Eliminates an assert in the strncpy/strncat checker caused by not validating a cast was successful. If the value of an argument was unknown, the cast would result in a NULL pointer which was later being dereferenced.

This fixes Bugzilla #9806.


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@130422 91177308-0d34-0410-b5e6-96231b3b80d8
---

diff --git a/lib/StaticAnalyzer/Checkers/CStringChecker.cpp b/lib/StaticAnalyzer/Checkers/CStringChecker.cpp
index 8e9c7899b0..534b887f3b 100644
--- a/lib/StaticAnalyzer/Checkers/CStringChecker.cpp
+++ b/lib/StaticAnalyzer/Checkers/CStringChecker.cpp
@@ -1017,8 +1017,15 @@ void CStringChecker::evalStrcpyCommon(CheckerContext &C, const CallExpr *CE,
     const Expr *lenExpr = CE->getArg(2);
     SVal lenVal = state->getSVal(lenExpr);
 
+    // Cast the length to a NonLoc SVal. If it is not a NonLoc then give up.
     NonLoc *strLengthNL = dyn_cast<NonLoc>(&strLength);
+    if (!strLengthNL)
+      return;
+
+    // Cast the max length to a NonLoc SVal. If it is not a NonLoc then give up.
     NonLoc *lenValNL = dyn_cast<NonLoc>(&lenVal);
+    if (!lenValNL)
+      return;
 
     QualType cmpTy = C.getSValBuilder().getContext().IntTy;
     const GRState *stateTrue, *stateFalse;