[llvm] r358852 - llvm-undname: Fix stack overflow on invalid found by oss-fuzz

[Nico Weber via llvm-commits]

Author: nico
Date: Sun Apr 21 07:25:07 2019
New Revision: 358852

URL: http://llvm.org/viewvc/llvm-project?rev=358852&view=rev
Log:
llvm-undname: Fix stack overflow on invalid found by oss-fuzz

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=358852&r1=358851&r2=358852&view=diff
==============================================================================
--- llvm/trunk/lib/Demangle/MicrosoftDemangle.cpp (original)
+++ llvm/trunk/lib/Demangle/MicrosoftDemangle.cpp Sun Apr 21 07:25:07 2019
@@ -1292,7 +1292,7 @@ Demangler::demangleStringLiteral(StringV
 
     unsigned BytesDecoded = 0;
     while (!MangledName.consumeFront('@')) {
-      if (MangledName.size() < 1)
+      if (MangledName.size() < 1 || BytesDecoded >= MaxStringByteLength)
         goto StringLiteralError;
       StringBytes[BytesDecoded++] = demangleCharLiteral(MangledName);
     }

Modified: llvm/trunk/test/Demangle/invalid-manglings.test
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/Demangle/invalid-manglings.test?rev=358852&r1=358851&r2=358852&view=diff
==============================================================================
--- llvm/trunk/test/Demangle/invalid-manglings.test (original)
+++ llvm/trunk/test/Demangle/invalid-manglings.test Sun Apr 21 07:25:07 2019
@@ -159,3 +159,8 @@
 ; CHECK-EMPTY:
 ; CHECK-NEXT: ??_C at _1301234567@a
 ; CHECK-NEXT: error: Invalid mangled name
+
+??_C at _0601234567@abcdefghijklmnopqrtsuvwxyzABCDEFGHIJKLMNOPQRTSUVWXYZabcdefghijklmnopqrtsuvwxyzABCDEFGHIJKLMNOPQRTSUVWXYZabcdefghijklmnopqrtsuvwxyz
+; CHECK-EMPTY:
+; CHECK-NEXT: ??_C at _0601234567@abcdefghijklmnopqrtsuvwxyzABCDEFGHIJKLMNOPQRTSUVWXYZabcdefghijklmnopqrtsuvwxyzABCDEFGHIJKLMNOPQRTSUVWXYZabcdefghijklmnopqrtsuvwxyz
+; CHECK-NEXT: error: Invalid mangled name