crashpad/util/linux/memory_map.h
Joshua Peraza d108fd04a5 linux: Add PtraceConnection::ReadFileContents
Some files, such as /proc/[pid]/maps, may not be accessible to the
handler. This enables the handler access to the contents of those files
via the broker.

This change reads maps and auxv using ReadFileContents.

Bug: crashpad:30
Change-Id: Ia19b498bae473c616ea794ab51c3f22afd5795be
Reviewed-on: https://chromium-review.googlesource.com/989406
Reviewed-by: Mark Mentovai <mark@chromium.org>
2018-04-03 22:08:29 +00:00

102 lines
3.7 KiB
C++

// Copyright 2017 The Crashpad Authors. All rights reserved.
//
// 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.
#ifndef CRASHPAD_UTIL_LINUX_MEMORY_MAP_H_
#define CRASHPAD_UTIL_LINUX_MEMORY_MAP_H_
#include <sys/types.h>
#include <string>
#include <vector>
#include "util/linux/address_types.h"
#include "util/linux/checked_linux_address_range.h"
#include "util/linux/ptrace_connection.h"
#include "util/misc/initialization_state_dcheck.h"
namespace crashpad {
//! \brief Accesses information about mapped memory in another process.
//!
//! The target process must be stopped to guarantee correct mappings. If the
//! target process is not stopped, mappings may be invalid after the return from
//! Initialize(), and even mappings existing at the time Initialize() was called
//! may not be found.
class MemoryMap {
public:
//! \brief Information about a mapped region of memory.
struct Mapping {
Mapping();
bool Equals(const Mapping& other) const;
std::string name;
CheckedLinuxAddressRange range;
off_t offset;
dev_t device;
ino_t inode;
bool readable;
bool writable;
bool executable;
bool shareable;
};
MemoryMap();
~MemoryMap();
//! \brief Initializes this object with information about the mapped memory
//! regions in the process connected via \a connection.
//!
//! This method must be called successfully prior to calling any other method
//! in this class. This method may only be called once.
//!
//! \param[in] connection A connection to the process create a map for.
//!
//! \return `true` on success, `false` on failure with a message logged.
bool Initialize(PtraceConnection* connection);
//! \return The Mapping containing \a address or `nullptr` if no match is
//! found. The caller does not take ownership of this object. It is scoped
//! to the lifetime of the MemoryMap object that it was obtained from.
const Mapping* FindMapping(LinuxVMAddress address) const;
//! \return The Mapping with the lowest base address whose name is \a name or
//! `nullptr` if no match is found. The caller does not take ownership of
//! this object. It is scoped to the lifetime of the MemoryMap object that
//! it was obtained from.
const Mapping* FindMappingWithName(const std::string& name) const;
//! \brief Find the first Mapping in a series of mappings for the same file.
//!
//! Executables and libaries are typically loaded into several mappings with
//! varying permissions for different segments. This method searches for the
//! mapping with the highest address at or below \a mapping, which maps the
//! same file as \a mapping from file offset 0.
//!
//! If \a mapping is not found, `nullptr` is returned. If \a mapping is found
//! but does not map a file, \a mapping is returned.
//!
//! \param[in] mapping A Mapping whose series to find the start of.
//! \return The first Mapping in the series or `nullptr` on failure with a
//! message logged.
const Mapping* FindFileMmapStart(const Mapping& mapping) const;
private:
std::vector<Mapping> mappings_;
InitializationStateDcheck initialized_;
};
} // namespace crashpad
#endif // CRASHPAD_UTIL_LINUX_MEMORY_MAP_H_