Fix potential missing nul character on resolved symbol names

third_party/tcmalloc/chromium/src/windows/addr2line-pdb.c

 /* Copyright (c) 2008, Google Inc.
  * All rights reserved.
- * 
+ *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are
  * met:
- * 
+ *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
  * copyright notice, this list of conditions and the following disclaimer
  * in the documentation and/or other materials provided with the
  * distribution.
  *     * Neither the name of Google Inc. nor the names of its
  * contributors may be used to endorse or promote products derived from
  * this software without specific prior written permission.
- * 
+ *
  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
  * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  *
  * ---
  * Author: David Vitek
  *
  * Dump function addresses using Microsoft debug symbols.  This works
  * on PDB files.  Note that this program will download symbols to
  * c:\websymbols without asking.
  */
 
 #ifndef WIN32_LEAN_AND_MEAN
 #define WIN32_LEAN_AND_MEAN
-#endif 
+#endif
 
 #ifndef _CRT_SECURE_NO_WARNINGS
 #define _CRT_SECURE_NO_WARNINGS
-#endif 
+#endif
 
 #ifndef _CRT_SECURE_NO_DEPRECATE
 #define _CRT_SECURE_NO_DEPRECATE
 #endif
 
 #include <stdio.h>
 #include <stdlib.h>
 
 #include <windows.h>
 #include <dbghelp.h>
@@ skipping 78 matching lines @@
   buf[sizeof(buf)-1] = '\0';  /* Just to be safe */
   while (fgets(buf, sizeof(buf)-1, stdin)) {
     /* GNU addr2line seems to just do a strtol and ignore any
      * weird characters it gets, so we will too.
      */
     unsigned __int64 reladdr = _strtoui64(buf, NULL, 16);
     ULONG64 buffer[(sizeof(SYMBOL_INFO) +
                     MAX_SYM_NAME*sizeof(TCHAR) +
                     sizeof(ULONG64) - 1)
                    / sizeof(ULONG64)];
+    memset(buffer, 0, sizeof(buffer));
     PSYMBOL_INFO pSymbol = (PSYMBOL_INFO)buffer;
     IMAGEHLP_LINE64 line;
     DWORD dummy;
 
     // Just ignore overflow. In an overflow scenario, the resulting address
     // will be lower than module_base which hasn't been mapped by any prior
     // SymLoadModuleEx() command. This will cause SymFromAddr() and
     // SymGetLineFromAddr64() both to return failures and print the correct
     // ?? and ??:0 message variant.
     ULONG64 absaddr = reladdr + module_base;
 
     pSymbol->SizeOfStruct = sizeof(SYMBOL_INFO);
-    pSymbol->MaxNameLen = MAX_SYM_NAME;
+    // The length of the name is not including the null-terminating character.
+    pSymbol->MaxNameLen = MAX_SYM_NAME - 1;
     if (print_function_name) {
       if (SymFromAddr(process, (DWORD64)absaddr, NULL, pSymbol)) {
         printf("%s\n", pSymbol->Name);
       } else {
         printf("??\n");
       }
     }
     line.SizeOfStruct = sizeof(IMAGEHLP_LINE64);
     if (SymGetLineFromAddr64(process, (DWORD64)absaddr, &dummy, &line)) {
       printf("%s:%d\n", line.FileName, (int)line.LineNumber);
     } else {
       printf("??:0\n");
     }
   }
   SymUnloadModule64(process, module_base);
   SymCleanup(process);
   return rv;
 }