[llvm] r271130 - Tighten some of the name map checks further

[David Majnemer via llvm-commits]

Author: majnemer
Date: Sat May 28 13:03:37 2016
New Revision: 271130

URL: http://llvm.org/viewvc/llvm-project?rev=271130&view=rev
Log:
Tighten some of the name map checks further

Modified:
    llvm/trunk/lib/DebugInfo/PDB/Raw/NameMap.cpp

Modified: llvm/trunk/lib/DebugInfo/PDB/Raw/NameMap.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/DebugInfo/PDB/Raw/NameMap.cpp?rev=271130&r1=271129&r2=271130&view=diff
==============================================================================
--- llvm/trunk/lib/DebugInfo/PDB/Raw/NameMap.cpp (original)
+++ llvm/trunk/lib/DebugInfo/PDB/Raw/NameMap.cpp Sat May 28 13:03:37 2016
@@ -50,7 +50,11 @@ Error NameMap::load(codeview::StreamRead
                       make_error<RawError>(raw_error_code::corrupt_file,
                                            "Expected name map max strings"));
 
-  const uint32_t MaxNumberOfWords = UINT32_MAX / sizeof(uint32_t);
+  if (MaxNumberOfStrings > (UINT32_MAX / sizeof(uint32_t)))
+    return make_error<RawError>(raw_error_code::corrupt_file,
+                                "Implausible number of strings");
+
+  const uint32_t MaxNumberOfWords = UINT32_MAX / (sizeof(uint32_t) * 8);
 
   // This appears to be a hash table which uses bitfields to determine whether
   // or not a bucket is 'present'.