81 lines
3.1 KiB
C++
81 lines
3.1 KiB
C++
//===- FuzzerExtraCountersWindows.cpp - Extra coverage counters for Win32 -===//
|
|
//
|
|
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
|
|
// See https://llvm.org/LICENSE.txt for license information.
|
|
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
|
|
//
|
|
//===----------------------------------------------------------------------===//
|
|
// Extra coverage counters defined by user code for Windows.
|
|
//===----------------------------------------------------------------------===//
|
|
|
|
#include "FuzzerPlatform.h"
|
|
#include <cstdint>
|
|
|
|
#if LIBFUZZER_WINDOWS
|
|
#include <windows.h>
|
|
|
|
namespace fuzzer {
|
|
|
|
//
|
|
// The __start___libfuzzer_extra_counters variable is align 16, size 16 to
|
|
// ensure the padding between it and the next variable in this section (either
|
|
// __libfuzzer_extra_counters or __stop___libfuzzer_extra_counters) will be
|
|
// located at (__start___libfuzzer_extra_counters +
|
|
// sizeof(__start___libfuzzer_extra_counters)). Otherwise, the calculation of
|
|
// (stop - (start + sizeof(start))) might be skewed.
|
|
//
|
|
// The section name, __libfuzzer_extra_countaaa ends with "aaa", so it sorts
|
|
// before __libfuzzer_extra_counters alphabetically. We want the start symbol to
|
|
// be placed in the section just before the user supplied counters (if present).
|
|
//
|
|
#pragma section(".data$__libfuzzer_extra_countaaa")
|
|
ATTRIBUTE_ALIGNED(16)
|
|
__declspec(allocate(".data$__libfuzzer_extra_countaaa")) uint8_t
|
|
__start___libfuzzer_extra_counters[16] = {0};
|
|
|
|
//
|
|
// Example of what the user-supplied counters should look like. First, the
|
|
// pragma to create the section name. It will fall alphabetically between
|
|
// ".data$__libfuzzer_extra_countaaa" and ".data$__libfuzzer_extra_countzzz".
|
|
// Next, the declspec to allocate the variable inside the specified section.
|
|
// Finally, some array, struct, whatever that is used to track the counter data.
|
|
// The size of this variable is computed at runtime by finding the difference of
|
|
// __stop___libfuzzer_extra_counters and __start___libfuzzer_extra_counters +
|
|
// sizeof(__start___libfuzzer_extra_counters).
|
|
//
|
|
|
|
//
|
|
// #pragma section(".data$__libfuzzer_extra_counters")
|
|
// __declspec(allocate(".data$__libfuzzer_extra_counters"))
|
|
// uint8_t any_name_variable[64 * 1024];
|
|
//
|
|
|
|
//
|
|
// Here, the section name, __libfuzzer_extra_countzzz ends with "zzz", so it
|
|
// sorts after __libfuzzer_extra_counters alphabetically. We want the stop
|
|
// symbol to be placed in the section just after the user supplied counters (if
|
|
// present). Align to 1 so there isn't any padding placed between this and the
|
|
// previous variable.
|
|
//
|
|
#pragma section(".data$__libfuzzer_extra_countzzz")
|
|
ATTRIBUTE_ALIGNED(1)
|
|
__declspec(allocate(".data$__libfuzzer_extra_countzzz")) uint8_t
|
|
__stop___libfuzzer_extra_counters = 0;
|
|
|
|
uint8_t *ExtraCountersBegin() {
|
|
return __start___libfuzzer_extra_counters +
|
|
sizeof(__start___libfuzzer_extra_counters);
|
|
}
|
|
|
|
uint8_t *ExtraCountersEnd() { return &__stop___libfuzzer_extra_counters; }
|
|
|
|
ATTRIBUTE_NO_SANITIZE_ALL
|
|
void ClearExtraCounters() {
|
|
uint8_t *Beg = ExtraCountersBegin();
|
|
SecureZeroMemory(Beg, ExtraCountersEnd() - Beg);
|
|
}
|
|
|
|
} // namespace fuzzer
|
|
|
|
#endif
|