Make possible to check memory allocations inside chromium

base/process/memory_linux.cc

 // Copyright (c) 2013 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 "base/process/memory.h"
 
 #include <new>
 
 #include "base/file_util.h"
 #include "base/files/file_path.h"
 #include "base/logging.h"
 #include "base/process/internal_linux.h"
 #include "base/strings/string_number_conversions.h"
+#include "third_party/tcmalloc/chromium/src/gperftools/tcmalloc.h"
 
 namespace base {
 
 size_t g_oom_size = 0U;
 
 namespace {
 
 void OnNoMemorySize(size_t size) {
   g_oom_size = size;
 
@@ skipping 92 matching lines @@
 }  // extern C
 
 #else
 
 // TODO(mostynb@opera.com): dlsym dance
 
 #endif  // LIBC_GLIBC && !USE_TCMALLOC
 
 #endif  // !*_SANITIZER
 
+bool UncheckedMalloc(size_t size, void** result) {
+#if defined(ADDRESS_SANITIZER) || defined(MEMORY_SANITIZER) || \
+    defined(THREAD_SANITIZER) || defined(LEAK_SANITIZER) || \
+    (!defined(LIBC_GLIBC) && !defined(USE_TCMALLOC))
+  *result = malloc(size);
+#elif defined(LIBC_GLIBC) && !defined(USE_TCMALLOC)
+  *result = __libc_malloc(size);
+#else // tcmalloc
+  *result = tc_malloc_skip_new_handler(size);
+#endif
+  return *result;
+}
+
+bool UncheckedCalloc(size_t num_items, size_t size, void** result) {
+  const size_t alloc_size = num_items * size;
+
+  // Overflow check
+  if (alloc_size && (alloc_size / size) != num_items)

[willchan no longer on Chromium, 2013/11/12 16:04:19]

Please add another set of parentheses around the != condition so people don't
have to remember the operator precedence rules.

What happens when |size| is 0? I don't know what happens for calloc(), but we
should be consistent at least. Is it OK to crash?

[kbalazs, 2013/11/12 18:40:46]

I made a mistake, the first part of the condition should be size not alloc_size.
Anyway, I will check what is the semantics of calloc in this regard.

+    return NULL;

[willchan no longer on Chromium, 2013/11/12 16:04:19]

Shouldn't this be return false?

+
+  if (!UncheckedMalloc(alloc_size, result))
+    return false;
+
+  memset(result, 0, alloc_size);
+  return true;
+}
+
 void EnableTerminationOnHeapCorruption() {
   // On Linux, there nothing to do AFAIK.
 }
 
 void EnableTerminationOnOutOfMemory() {
 #if defined(OS_ANDROID)
   // Android doesn't support setting a new handler.
   DLOG(WARNING) << "Not feasible.";
 #else
   // Set the new-out of memory handler.
@@ skipping 38 matching lines @@
     int score_len = static_cast<int>(score_str.length());
     return (score_len == file_util::WriteFile(oom_file,
                                               score_str.c_str(),
                                               score_len));
   }
 
   return false;
 }
 
 }  // namespace base