You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
113 lines
3.1 KiB
113 lines
3.1 KiB
4 months ago
|
/*
|
||
|
|
* Copyright (C) 2013 The Android Open Source Project
|
||
|
|
*
|
||
|
|
* Licensed under the Apache License, Version 2.0 (the "License");
|
||
|
|
* you may not use this file except in compliance with the License.
|
||
|
|
* You may obtain a copy of the License at
|
||
|
|
*
|
||
|
|
* http://www.apache.org/licenses/LICENSE-2.0
|
||
|
|
*
|
||
|
|
* Unless required by applicable law or agreed to in writing, software
|
||
|
|
* distributed under the License is distributed on an "AS IS" BASIS,
|
||
|
|
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
|
||
|
|
* See the License for the specific language governing permissions and
|
||
|
|
* limitations under the License.
|
||
|
|
*/
|
||
|
|
|
||
|
|
#include <errno.h>
|
||
|
|
#include <stdint.h>
|
||
|
|
#include <string.h>
|
||
|
|
#include <sys/param.h>
|
||
|
|
#include <sys/ptrace.h>
|
||
|
|
#include <sys/types.h>
|
||
|
|
#include <ucontext.h>
|
||
|
|
#include <unistd.h>
|
||
|
|
|
||
|
|
#include <backtrace/Backtrace.h>
|
||
|
|
#include <backtrace/BacktraceMap.h>
|
||
|
|
|
||
|
|
#include "BacktraceLog.h"
|
||
|
|
#include "BacktracePtrace.h"
|
||
|
|
|
||
|
|
#if !defined(__APPLE__)
|
||
|
|
static bool PtraceRead(pid_t tid, uint64_t addr, word_t* out_value) {
|
||
|
|
// ptrace() returns -1 and sets errno when the operation fails.
|
||
|
|
// To disambiguate -1 from a valid result, we clear errno beforehand.
|
||
|
|
errno = 0;
|
||
|
|
*out_value = ptrace(PTRACE_PEEKTEXT, tid, reinterpret_cast<void*>(addr), nullptr);
|
||
|
|
if (*out_value == static_cast<word_t>(-1) && errno) {
|
||
|
|
return false;
|
||
|
|
}
|
||
|
|
return true;
|
||
|
|
}
|
||
|
|
#endif
|
||
|
|
|
||
|
|
bool BacktracePtrace::ReadWord(uint64_t ptr, word_t* out_value) {
|
||
|
|
#if defined(__APPLE__)
|
||
|
|
BACK_LOGW("MacOS does not support reading from another pid.");
|
||
|
|
return false;
|
||
|
|
#else
|
||
|
|
if (!VerifyReadWordArgs(ptr, out_value)) {
|
||
|
|
return false;
|
||
|
|
}
|
||
|
|
|
||
|
|
backtrace_map_t map;
|
||
|
|
FillInMap(ptr, &map);
|
||
|
|
if (!BacktraceMap::IsValid(map) || !(map.flags & PROT_READ)) {
|
||
|
|
return false;
|
||
|
|
}
|
||
|
|
|
||
|
|
return PtraceRead(Tid(), ptr, out_value);
|
||
|
|
#endif
|
||
|
|
}
|
||
|
|
|
||
|
|
size_t BacktracePtrace::Read(uint64_t addr, uint8_t* buffer, size_t bytes) {
|
||
|
|
#if defined(__APPLE__)
|
||
|
|
BACK_LOGW("MacOS does not support reading from another pid.");
|
||
|
|
return 0;
|
||
|
|
#else
|
||
|
|
backtrace_map_t map;
|
||
|
|
FillInMap(addr, &map);
|
||
|
|
if (!BacktraceMap::IsValid(map) || !(map.flags & PROT_READ)) {
|
||
|
|
return 0;
|
||
|
|
}
|
||
|
|
|
||
|
|
bytes = MIN(map.end - addr, bytes);
|
||
|
|
size_t bytes_read = 0;
|
||
|
|
word_t data_word;
|
||
|
|
size_t align_bytes = addr & (sizeof(word_t) - 1);
|
||
|
|
if (align_bytes != 0) {
|
||
|
|
if (!PtraceRead(Tid(), addr & ~(sizeof(word_t) - 1), &data_word)) {
|
||
|
|
return 0;
|
||
|
|
}
|
||
|
|
size_t copy_bytes = MIN(sizeof(word_t) - align_bytes, bytes);
|
||
|
|
memcpy(buffer, reinterpret_cast<uint8_t*>(&data_word) + align_bytes, copy_bytes);
|
||
|
|
addr += copy_bytes;
|
||
|
|
buffer += copy_bytes;
|
||
|
|
bytes -= copy_bytes;
|
||
|
|
bytes_read += copy_bytes;
|
||
|
|
}
|
||
|
|
|
||
|
|
size_t num_words = bytes / sizeof(word_t);
|
||
|
|
for (size_t i = 0; i < num_words; i++) {
|
||
|
|
if (!PtraceRead(Tid(), addr, &data_word)) {
|
||
|
|
return bytes_read;
|
||
|
|
}
|
||
|
|
memcpy(buffer, &data_word, sizeof(word_t));
|
||
|
|
buffer += sizeof(word_t);
|
||
|
|
addr += sizeof(word_t);
|
||
|
|
bytes_read += sizeof(word_t);
|
||
|
|
}
|
||
|
|
|
||
|
|
size_t left_over = bytes & (sizeof(word_t) - 1);
|
||
|
|
if (left_over) {
|
||
|
|
if (!PtraceRead(Tid(), addr, &data_word)) {
|
||
|
|
return bytes_read;
|
||
|
|
}
|
||
|
|
memcpy(buffer, &data_word, left_over);
|
||
|
|
bytes_read += left_over;
|
||
|
|
}
|
||
|
|
return bytes_read;
|
||
|
|
#endif
|
||
|
|
}
|