[llvm] r271145 - [SymbolDumper] Validate the string table offset before using it

[David Majnemer via llvm-commits]

Author: majnemer
Date: Sat May 28 15:04:46 2016
New Revision: 271145

URL: http://llvm.org/viewvc/llvm-project?rev=271145&view=rev
Log:
[SymbolDumper] Validate the string table offset before using it

Modified:
    llvm/trunk/lib/DebugInfo/CodeView/SymbolDumper.cpp

Modified: llvm/trunk/lib/DebugInfo/CodeView/SymbolDumper.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/DebugInfo/CodeView/SymbolDumper.cpp?rev=271145&r1=271144&r2=271145&view=diff
==============================================================================
--- llvm/trunk/lib/DebugInfo/CodeView/SymbolDumper.cpp (original)
+++ llvm/trunk/lib/DebugInfo/CodeView/SymbolDumper.cpp Sat May 28 15:04:46 2016
@@ -591,12 +591,12 @@ void CVSymbolDumperImpl::visitDefRangeSu
 
   if (ObjDelegate) {
     StringRef StringTable = ObjDelegate->getStringTable();
-    if (!StringTable.empty()) {
-      W.printString("Program",
-                    StringTable.drop_front(DefRangeSubfield.Header.Program)
-                        .split('\0')
-                        .first);
-    }
+    auto ProgramStringTableOffset = DefRangeSubfield.Header.Program;
+    if (ProgramStringTableOffset >= StringTable.size())
+      return parseError();
+    StringRef Program =
+        StringTable.drop_front(ProgramStringTableOffset).split('\0').first;
+    W.printString("Program", Program);
   }
   W.printNumber("OffsetInParent", DefRangeSubfield.Header.OffsetInParent);
   printLocalVariableAddrRange(DefRangeSubfield.Header.Range,