SandboxedExtensionUnpacker::ValidateSignature should check for an empty signa...

chrome/browser/extensions/sandboxed_extension_unpacker.cc

 // Copyright (c) 2010 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "chrome/browser/extensions/sandboxed_extension_unpacker.h"
 
 #include <set>
 
 #include "base/base64.h"
 #include "base/crypto/signature_verifier.h"
@@ skipping 210 matching lines @@
   }
   if (header.key_size > kMaxPublicKeySize ||
       header.signature_size > kMaxSignatureSize) {
     ReportFailure("Excessively large key or signature");
     return false;
   }
   if (header.key_size == 0) {
     ReportFailure("Key length is zero");
     return false;
   }
+  if (header.signature_size == 0) {
+    ReportFailure("Signature length is zero");
+    return false;
+  }
 
   std::vector<uint8> key;
   key.resize(header.key_size);
   len = fread(&key.front(), sizeof(uint8), header.key_size, file.get());
   if (len < header.key_size) {
     ReportFailure("Invalid public key");
     return false;
   }
 
   std::vector<uint8> signature;
@@ skipping 170 matching lines @@
     if (!file_util::WriteFile(path,
                               catalog_json.c_str(),
                               catalog_json.size())) {
       ReportFailure("Error saving catalog.");
       return false;
     }
   }
 
   return true;
 }