platform_bionic/libc/malloc_debug/GuardData.cpp
Christopher Ferris 2b2b25b878 Refactor Config from a struct to a class.
This should make it easier to add new options, and to add options that
are complex. For example, I want to modify the behavior of
record_allocs_file so that it also enables record_allocs to a default
state.

Test: All unit tests pass.
Test: Enable the backtrace option and restart.
Change-Id: Idf5cdeed06ade3bc2c8ae39d228734bf65209b4f
2017-04-06 15:30:42 -07:00

100 lines
3.9 KiB
C++

/*
* Copyright (C) 2015 The Android Open Source Project
* 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.
*
* 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.
*/
#include <stdint.h>
#include <string.h>
#include <vector>
#include "backtrace.h"
#include "Config.h"
#include "debug_disable.h"
#include "debug_log.h"
#include "DebugData.h"
#include "malloc_debug.h"
#include "GuardData.h"
GuardData::GuardData(DebugData* debug_data, int init_value, size_t num_bytes)
: OptionData(debug_data) {
// Create a buffer for fast comparisons of the front guard.
cmp_mem_.resize(num_bytes);
memset(cmp_mem_.data(), init_value, cmp_mem_.size());
}
void GuardData::LogFailure(const Header* header, const void* pointer, const void* data) {
error_log(LOG_DIVIDER);
error_log("+++ ALLOCATION %p SIZE %zu HAS A CORRUPTED %s GUARD", pointer,
header->real_size(), GetTypeName());
// Log all of the failing bytes.
const uint8_t* expected = cmp_mem_.data();
int pointer_idx = reinterpret_cast<uintptr_t>(data) - reinterpret_cast<uintptr_t>(pointer);
const uint8_t* real = reinterpret_cast<const uint8_t*>(data);
for (size_t i = 0; i < cmp_mem_.size(); i++, pointer_idx++) {
if (real[i] != expected[i]) {
error_log(" allocation[%d] = 0x%02x (expected 0x%02x)", pointer_idx, real[i], expected[i]);
}
}
error_log("Backtrace at time of failure:");
std::vector<uintptr_t> frames(64);
size_t frame_num = backtrace_get(frames.data(), frames.size());
frames.resize(frame_num);
backtrace_log(frames.data(), frames.size());
error_log(LOG_DIVIDER);
}
FrontGuardData::FrontGuardData(DebugData* debug_data, const Config& config, size_t* offset)
: GuardData(debug_data, config.front_guard_value(), config.front_guard_bytes()) {
// Create a buffer for fast comparisons of the front guard.
cmp_mem_.resize(config.front_guard_bytes());
memset(cmp_mem_.data(), config.front_guard_value(), cmp_mem_.size());
// Assumes that front_bytes is a multiple of MINIMUM_ALIGNMENT_BYTES.
offset_ = *offset;
*offset += config.front_guard_bytes();
}
bool FrontGuardData::Valid(const Header* header) {
return GuardData::Valid(debug_->GetFrontGuard(header));
}
void FrontGuardData::LogFailure(const Header* header) {
GuardData::LogFailure(header, debug_->GetPointer(header), debug_->GetFrontGuard(header));
}
RearGuardData::RearGuardData(DebugData* debug_data, const Config& config)
: GuardData(debug_data, config.rear_guard_value(), config.rear_guard_bytes()) {
}
bool RearGuardData::Valid(const Header* header) {
return GuardData::Valid(debug_->GetRearGuard(header));
}
void RearGuardData::LogFailure(const Header* header) {
GuardData::LogFailure(header, debug_->GetPointer(header), debug_->GetRearGuard(header));
}