[SymbolDumper] Validate the string table offset before using it

llvm-svn: 271142

1 files changed, 6 insertions, 5 deletions

diff --git a/llvm/lib/DebugInfo/CodeView/SymbolDumper.cpp b/llvm/lib/DebugInfo/CodeView/SymbolDumper.cpp
index e2dc9d5b76d..4afcdf189f2 100644
--- a/llvm/lib/DebugInfo/CodeView/SymbolDumper.cpp
+++ b/llvm/lib/DebugInfo/CodeView/SymbolDumper.cpp
@@ -610,11 +610,12 @@ void CVSymbolDumperImpl::visitDefRangeSym(SymbolKind Kind,
 
   if (ObjDelegate) {
     StringRef StringTable = ObjDelegate->getStringTable();
-    if (!StringTable.empty()) {
-      W.printString(
-          "Program",
-          StringTable.drop_front(DefRange.Header.Program).split('\0').first);
-    }
+    auto ProgramStringTableOffset = DefRange.Header.Program;
+    if (ProgramStringTableOffset >= StringTable.size())
+      return parseError();
+    StringRef Program =
+        StringTable.drop_front(ProgramStringTableOffset).split('\0').first;
+    W.printString("Program", Program);
   }
   printLocalVariableAddrRange(DefRange.Header.Range,
                               DefRange.getRelocationOffset());