Base: account for calloc aborting in security unittests

base/security_unittest.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 <fcntl.h>
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
 #include <sys/stat.h>
 #include <sys/types.h>
@@ skipping 19 matching lines @@
 
 // This function acts as a compiler optimization barrier. We use it to
 // prevent the compiler from making an expression a compile-time constant.
 // We also use it so that the compiler doesn't discard certain return values
 // as something we don't need (see the comment with calloc below).
 template <typename Type>
 Type HideValueFromCompiler(volatile Type value) {
   return value;
 }
 
-// Check that we can not allocate a memory range that cannot be indexed
-// via an int. This is used to mitigate vulnerabilities in libraries that use
-// int instead of size_t.
-// See crbug.com/169327.
-
-// - NO_TCMALLOC because we only patched tcmalloc
+// - NO_TCMALLOC (should be defined if we compile with linux_use_tcmalloc=0)
 // - ADDRESS_SANITIZER because it has its own memory allocator
-// - IOS does not seem to honor nothrow in new properly
+// - IOS does not use tcmalloc
 // - OS_MACOSX does not use tcmalloc
 #if !defined(NO_TCMALLOC) && !defined(ADDRESS_SANITIZER) && \
     !defined(OS_IOS) && !defined(OS_MACOSX)
-  #define ALLOC_TEST(function) function
+  #define TCMALLOC_TEST(function) function
 #else
-  #define ALLOC_TEST(function) DISABLED_##function
+  #define TCMALLOC_TEST(function) DISABLED_##function
 #endif
 
 // TODO(jln): switch to std::numeric_limits<int>::max() when we switch to
 // C++11.
 const size_t kTooBigAllocSize = INT_MAX;
 
 // Detect runtime TCMalloc bypasses.
 bool IsTcMallocBypassed() {
 #if defined(OS_LINUX) || defined(OS_CHROMEOS)
   // This should detect a TCMalloc bypass from Valgrind.
   char* g_slice = getenv("G_SLICE");
   if (g_slice && !strcmp(g_slice, "always-malloc"))
     return true;
 #endif
   return false;
 }
 
+bool CallocDiesOnOOM() {
+// The wrapper function in base/process_util_linux.cc that is used when we
+// compile without TCMalloc will just die on OOM instead of returning NULL.
+#if defined(OS_LINUX) && defined(NO_TCMALLOC)
+  return true;
+#else
+  return false;
+#endif
+}
+
 // Fake test that allow to know the state of TCMalloc by looking at bots.
-TEST(SecurityTest, ALLOC_TEST(IsTCMallocDynamicallyBypassed)) {
+TEST(SecurityTest, TCMALLOC_TEST(IsTCMallocDynamicallyBypassed)) {
   printf("Malloc is dynamically bypassed: %s\n",
          IsTcMallocBypassed() ? "yes." : "no.");
 }
 
-TEST(SecurityTest, ALLOC_TEST(MemoryAllocationRestrictionsMalloc)) {
+// The MemoryAllocationRestrictions* tests test that we can not allocate a
+// memory range that cannot be indexed via an int. This is used to mitigate
+// vulnerabilities in libraries that use int instead of size_t.  See
+// crbug.com/169327.
+
+TEST(SecurityTest, TCMALLOC_TEST(MemoryAllocationRestrictionsMalloc)) {
   if (!IsTcMallocBypassed()) {
     scoped_ptr<char, base::FreeDeleter> ptr(static_cast<char*>(
         HideValueFromCompiler(malloc(kTooBigAllocSize))));
     ASSERT_TRUE(!ptr);
   }
 }
 
-TEST(SecurityTest, ALLOC_TEST(MemoryAllocationRestrictionsCalloc)) {
+TEST(SecurityTest, TCMALLOC_TEST(MemoryAllocationRestrictionsCalloc)) {
   if (!IsTcMallocBypassed()) {
     scoped_ptr<char, base::FreeDeleter> ptr(static_cast<char*>(
         HideValueFromCompiler(calloc(kTooBigAllocSize, 1))));
     ASSERT_TRUE(!ptr);
   }
 }
 
-TEST(SecurityTest, ALLOC_TEST(MemoryAllocationRestrictionsRealloc)) {
+TEST(SecurityTest, TCMALLOC_TEST(MemoryAllocationRestrictionsRealloc)) {
   if (!IsTcMallocBypassed()) {
     char* orig_ptr = static_cast<char*>(malloc(1));
     ASSERT_TRUE(orig_ptr);
     scoped_ptr<char, base::FreeDeleter> ptr(static_cast<char*>(
         HideValueFromCompiler(realloc(orig_ptr, kTooBigAllocSize))));
     ASSERT_TRUE(!ptr);
     // If realloc() did not succeed, we need to free orig_ptr.
     free(orig_ptr);
   }
 }
 
 typedef struct {
   char large_array[kTooBigAllocSize];
 } VeryLargeStruct;
 
-TEST(SecurityTest, ALLOC_TEST(MemoryAllocationRestrictionsNew)) {
+TEST(SecurityTest, TCMALLOC_TEST(MemoryAllocationRestrictionsNew)) {
   if (!IsTcMallocBypassed()) {
     scoped_ptr<VeryLargeStruct> ptr(
         HideValueFromCompiler(new (nothrow) VeryLargeStruct));
     ASSERT_TRUE(!ptr);
   }
 }
 
-TEST(SecurityTest, ALLOC_TEST(MemoryAllocationRestrictionsNewArray)) {
+TEST(SecurityTest, TCMALLOC_TEST(MemoryAllocationRestrictionsNewArray)) {
   if (!IsTcMallocBypassed()) {
     scoped_ptr<char[]> ptr(
         HideValueFromCompiler(new (nothrow) char[kTooBigAllocSize]));
     ASSERT_TRUE(!ptr);
   }
 }
 
 // The tests bellow check for overflows in new[] and calloc().
 
 #if defined(OS_IOS) || defined(OS_WIN)
@@ skipping 49 matching lines @@
     OverflowTestsSoftExpectTrue(!array_pointer);
   }
   {
     scoped_ptr<char[][kArraySize2]> array_pointer(new (nothrow)
         char[kDynamicArraySize][kArraySize2]);
     OverflowTestsSoftExpectTrue(!array_pointer);
   }
 }
 #endif
 
+// Call calloc(), eventually free the memory and return whether or not
+// calloc() did succeed.
+bool CallocReturnsNull(size_t nmemb, size_t size) {
+  scoped_ptr<char, base::FreeDeleter> array_pointer(
+      static_cast<char*>(calloc(nmemb, size)));
+  // We need the call to HideValueFromCompiler(): we have seen LLVM
+  // optimize away the call to calloc() entirely and assume
+  // the pointer to not be NULL.
+  return HideValueFromCompiler(array_pointer.get()) == NULL;
+}
+
 // Test if calloc() can overflow. Disable on ASAN for now since the
-// overflow seems present there.
+// overflow seems present there (crbug.com/175554).
 TEST(SecurityTest, DISABLE_ON_ASAN(CallocOverflow)) {
   const size_t kArraySize = 4096;
   const size_t kMaxSizeT = numeric_limits<size_t>::max();
   const size_t kArraySize2 = kMaxSizeT / kArraySize + 10;
-  {
-    scoped_ptr<char> array_pointer(
-        static_cast<char*>(calloc(kArraySize, kArraySize2)));
-    // We need the call to HideValueFromCompiler(): we have seen LLVM
-    // optimize away the call to calloc() entirely and assume
-    // the pointer to not be NULL.
-    EXPECT_TRUE(HideValueFromCompiler(array_pointer.get()) == NULL);
-  }
-  {
-    scoped_ptr<char> array_pointer(
-        static_cast<char*>(calloc(kArraySize2, kArraySize)));
-    // We need the call to HideValueFromCompiler(): we have seen LLVM
-    // optimize away the call to calloc() entirely and assume
-    // the pointer to not be NULL.
-    EXPECT_TRUE(HideValueFromCompiler(array_pointer.get()) == NULL);
+  if (!CallocDiesOnOOM()) {
+    EXPECT_TRUE(CallocReturnsNull(kArraySize, kArraySize2));
+    EXPECT_TRUE(CallocReturnsNull(kArraySize2, kArraySize));
+  } else {
+    // It's also ok for calloc to just terminate the process.
+#if defined(GTEST_HAS_DEATH_TEST)
+    EXPECT_DEATH(CallocReturnsNull(kArraySize, kArraySize2), "");
+    EXPECT_DEATH(CallocReturnsNull(kArraySize2, kArraySize), "");
+#endif  // GTEST_HAS_DEATH_TEST
   }
 }
 
 #if (defined(OS_LINUX) || defined(OS_CHROMEOS)) && defined(__x86_64__)
 // Useful for debugging.
 void PrintProcSelfMaps() {
   int fd = open("/proc/self/maps", O_RDONLY);
   file_util::ScopedFD fd_closer(&fd);
   ASSERT_GE(fd, 0);
   char buffer[1<<13];
   int ret;
   ret = read(fd, buffer, sizeof(buffer) - 1);
   ASSERT_GT(ret, 0);
   buffer[ret - 1] = 0;
   fprintf(stdout, "%s\n", buffer);
 }
 
 // Check if ptr1 and ptr2 are separated by less than size chars.
 bool ArePointersToSameArea(void* ptr1, void* ptr2, size_t size) {
   ptrdiff_t ptr_diff = reinterpret_cast<char*>(std::max(ptr1, ptr2)) -
                        reinterpret_cast<char*>(std::min(ptr1, ptr2));
   return static_cast<size_t>(ptr_diff) <= size;
 }
 
 // Check if TCMalloc uses an underlying random memory allocator.
-TEST(SecurityTest, ALLOC_TEST(RandomMemoryAllocations)) {
+TEST(SecurityTest, TCMALLOC_TEST(RandomMemoryAllocations)) {
   if (IsTcMallocBypassed())
     return;
   size_t kPageSize = 4096;  // We support x86_64 only.
   // Check that malloc() returns an address that is neither the kernel's
   // un-hinted mmap area, nor the current brk() area. The first malloc() may
   // not be at a random address because TCMalloc will first exhaust any memory
   // that it has allocated early on, before starting the sophisticated
   // allocators.
   void* default_mmap_heap_address =
       mmap(0, kPageSize, PROT_READ|PROT_WRITE,
@@ skipping 29 matching lines @@
   // kRandomMask, so we use it as an additional detection mechanism.
   const uintptr_t kRandomMask = 0x3fffffffffffULL;
   bool impossible_random_address =
       reinterpret_cast<uintptr_t>(ptr.get()) & ~kRandomMask;
   EXPECT_FALSE(impossible_random_address);
 }
 
 #endif  // (defined(OS_LINUX) || defined(OS_CHROMEOS)) && defined(__x86_64__)
 
 }  // namespace