[llvm] r358367 - llvm-undname: Fix oss-fuzz-foudn crash-on-invalid with incomplete special table nodes

[Nico Weber via llvm-commits]

Author: nico
Date: Sun Apr 14 16:32:37 2019
New Revision: 358367

URL: http://llvm.org/viewvc/llvm-project?rev=358367&view=rev
Log:
llvm-undname: Fix oss-fuzz-foudn crash-on-invalid with incomplete special table nodes

Modified:
    llvm/trunk/lib/Demangle/MicrosoftDemangle.cpp
    llvm/trunk/test/Demangle/invalid-manglings.test

Modified: llvm/trunk/lib/Demangle/MicrosoftDemangle.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Demangle/MicrosoftDemangle.cpp?rev=358367&r1=358366&r2=358367&view=diff
==============================================================================
--- llvm/trunk/lib/Demangle/MicrosoftDemangle.cpp (original)
+++ llvm/trunk/lib/Demangle/MicrosoftDemangle.cpp Sun Apr 14 16:32:37 2019
@@ -276,6 +276,10 @@ Demangler::demangleSpecialTableSymbolNod
   SpecialTableSymbolNode *STSN = Arena.alloc<SpecialTableSymbolNode>();
   STSN->Name = QN;
   bool IsMember = false;
+  if (MangledName.empty()) {
+    Error = true;
+    return nullptr;
+  }
   char Front = MangledName.popFront();
   if (Front != '6' && Front != '7') {
     Error = true;

Modified: llvm/trunk/test/Demangle/invalid-manglings.test
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/Demangle/invalid-manglings.test?rev=358367&r1=358366&r2=358367&view=diff
==============================================================================
--- llvm/trunk/test/Demangle/invalid-manglings.test (original)
+++ llvm/trunk/test/Demangle/invalid-manglings.test Sun Apr 14 16:32:37 2019
@@ -119,3 +119,13 @@
 ; CHECK-EMPTY:
 ; CHECK-NEXT: ?foo@?$?_
 ; CHECK-NEXT: error: Invalid mangled name
+
+??_R4
+; CHECK-EMPTY:
+; CHECK-NEXT: ??_R4
+; CHECK-NEXT: error: Invalid mangled name
+
+??_R4foo@@
+; CHECK-EMPTY:
+; CHECK-NEXT: ??_R4foo@@
+; CHECK-NEXT: error: Invalid mangled name