ACPR/android_system_core
1
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity Actions
android_system_core/init/service.h
Jiyong Park 6866041ff0 Proper mount namespace configuration for bionic 
This CL fixes the design problem of the previous mechanism for providing
the bootstrap bionic and the runtime bionic to the same path.

Previously, bootstrap bionic was self-bind-mounted; i.e.
/system/bin/libc.so is bind-mounted to itself. And the runtime bionic
was bind-mounted on top of the bootstrap bionic. This has not only caused
problems like `adb sync` not working(b/122737045), but also is quite
difficult to understand due to the double-and-self mounting.

This is the new design:

Most importantly, these four are all distinct:
1) bootstrap bionic (/system/lib/bootstrap/libc.so)
2) runtime bionic (/apex/com.android.runtime/lib/bionic/libc.so)
3) mount point for 1) and 2) (/bionic/lib/libc.so)
4) symlink for 3) (/system/lib/libc.so -> /bionic/lib/libc.so)

Inside the mount namespace of the pre-apexd processes, 1) is
bind-mounted to 3). Likewise, inside the mount namespace of the
post-apexd processes, 2) is bind-mounted to 3). In other words, there is
no self-mount, and no double-mount.

Another change is that mount points are under /bionic and the legacy
paths become symlinks to the mount points. This is to make sure that
there is no bind mounts under /system, which is breaking some apps.

Finally, code for creating mount namespaces, mounting bionic, etc are
refactored to mount_namespace.cpp

Bug: 120266448
Bug: 123275379
Test: m, device boots, adb sync/push/pull works,
especially with following paths:
/bionic/lib64/libc.so
/bionic/bin/linker64
/system/lib64/bootstrap/libc.so
/system/bin/bootstrap/linker64
Change-Id: Icdfbdcc1efca540ac854d4df79e07ee61fca559f
2019-01-30 19:18:22 +09:00

321 lines
12 KiB
C++
Raw Blame History

/*
* Copyright (C) 2015 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.
*/
#ifndef _INIT_SERVICE_H
#define _INIT_SERVICE_H
#include <signal.h>
#include <sys/resource.h>
#include <sys/types.h>
#include <chrono>
#include <memory>
#include <optional>
#include <set>
#include <string>
#include <vector>
#include <android-base/chrono_utils.h>
#include <cutils/iosched_policy.h>
#include "action.h"
#include "capabilities.h"
#include "descriptors.h"
#include "keyword_map.h"
#include "parser.h"
#include "subcontext.h"
#define SVC_DISABLED 0x001 // do not autostart with class
#define SVC_ONESHOT 0x002 // do not restart on exit
#define SVC_RUNNING 0x004 // currently active
#define SVC_RESTARTING 0x008 // waiting to restart
#define SVC_CONSOLE 0x010 // requires console
#define SVC_CRITICAL 0x020 // will reboot into bootloader if keeps crashing
#define SVC_RESET 0x040 // Use when stopping a process,
// but not disabling so it can be restarted with its class.
#define SVC_RC_DISABLED 0x080 // Remember if the disabled flag was set in the rc script.
#define SVC_RESTART 0x100 // Use to safely restart (stop, wait, start) a service.
#define SVC_DISABLED_START 0x200 // A start was requested but it was disabled at the time.
#define SVC_EXEC 0x400 // This service was started by either 'exec' or 'exec_start' and stops
// init from processing more commands until it completes
#define SVC_SHUTDOWN_CRITICAL 0x800 // This service is critical for shutdown and
// should not be killed during shutdown
#define SVC_TEMPORARY 0x1000 // This service was started by 'exec' and should be removed from the
// service list once it is reaped.
#define NR_SVC_SUPP_GIDS 12 // twelve supplementary groups
namespace android {
namespace init {
class Service {
public:
Service(const std::string& name, Subcontext* subcontext_for_restart_commands,
const std::vector<std::string>& args);
Service(const std::string& name, unsigned flags, uid_t uid, gid_t gid,
const std::vector<gid_t>& supp_gids, const CapSet& capabilities,
unsigned namespace_flags, const std::string& seclabel,
Subcontext* subcontext_for_restart_commands, const std::vector<std::string>& args);
static std::unique_ptr<Service> MakeTemporaryOneshotService(const std::vector<std::string>& args);
bool IsRunning() { return (flags_ & SVC_RUNNING) != 0; }
Result<Success> ParseLine(std::vector<std::string>&& args);
Result<Success> ExecStart();
Result<Success> Start();
Result<Success> StartIfNotDisabled();
Result<Success> Enable();
void Reset();
void Stop();
void Terminate();
void Timeout();
void Restart();
void Reap(const siginfo_t& siginfo);
void DumpState() const;
void SetShutdownCritical() { flags_ |= SVC_SHUTDOWN_CRITICAL; }
bool IsShutdownCritical() const { return (flags_ & SVC_SHUTDOWN_CRITICAL) != 0; }
void UnSetExec() {
is_exec_service_running_ = false;
flags_ &= ~SVC_EXEC;
}
void AddReapCallback(std::function<void(const siginfo_t& siginfo)> callback) {
reap_callbacks_.emplace_back(std::move(callback));
}
static bool is_exec_service_running() { return is_exec_service_running_; }
const std::string& name() const { return name_; }
const std::set<std::string>& classnames() const { return classnames_; }
unsigned flags() const { return flags_; }
pid_t pid() const { return pid_; }
android::base::boot_clock::time_point time_started() const { return time_started_; }
int crash_count() const { return crash_count_; }
uid_t uid() const { return uid_; }
gid_t gid() const { return gid_; }
unsigned namespace_flags() const { return namespace_flags_; }
const std::vector<gid_t>& supp_gids() const { return supp_gids_; }
const std::string& seclabel() const { return seclabel_; }
const std::vector<int>& keycodes() const { return keycodes_; }
IoSchedClass ioprio_class() const { return ioprio_class_; }
int ioprio_pri() const { return ioprio_pri_; }
const std::set<std::string>& interfaces() const { return interfaces_; }
int priority() const { return priority_; }
int oom_score_adjust() const { return oom_score_adjust_; }
bool is_override() const { return override_; }
bool process_cgroup_empty() const { return process_cgroup_empty_; }
unsigned long start_order() const { return start_order_; }
void set_sigstop(bool value) { sigstop_ = value; }
std::chrono::seconds restart_period() const { return restart_period_; }
std::optional<std::chrono::seconds> timeout_period() const { return timeout_period_; }
const std::vector<std::string>& args() const { return args_; }
bool is_updatable() const { return updatable_; }
private:
using OptionParser = Result<Success> (Service::*)(std::vector<std::string>&& args);
class OptionParserMap;
Result<Success> SetUpMountNamespace() const;
Result<Success> SetUpPidNamespace() const;
Result<Success> EnterNamespaces() const;
void NotifyStateChange(const std::string& new_state) const;
void StopOrReset(int how);
void ZapStdio() const;
void OpenConsole() const;
void KillProcessGroup(int signal);
void SetProcessAttributes();
Result<Success> ParseCapabilities(std::vector<std::string>&& args);
Result<Success> ParseClass(std::vector<std::string>&& args);
Result<Success> ParseConsole(std::vector<std::string>&& args);
Result<Success> ParseCritical(std::vector<std::string>&& args);
Result<Success> ParseDisabled(std::vector<std::string>&& args);
Result<Success> ParseEnterNamespace(std::vector<std::string>&& args);
Result<Success> ParseGroup(std::vector<std::string>&& args);
Result<Success> ParsePriority(std::vector<std::string>&& args);
Result<Success> ParseInterface(std::vector<std::string>&& args);
Result<Success> ParseIoprio(std::vector<std::string>&& args);
Result<Success> ParseKeycodes(std::vector<std::string>&& args);
Result<Success> ParseOneshot(std::vector<std::string>&& args);
Result<Success> ParseOnrestart(std::vector<std::string>&& args);
Result<Success> ParseOomScoreAdjust(std::vector<std::string>&& args);
Result<Success> ParseOverride(std::vector<std::string>&& args);
Result<Success> ParseMemcgLimitInBytes(std::vector<std::string>&& args);
Result<Success> ParseMemcgLimitPercent(std::vector<std::string>&& args);
Result<Success> ParseMemcgLimitProperty(std::vector<std::string>&& args);
Result<Success> ParseMemcgSoftLimitInBytes(std::vector<std::string>&& args);
Result<Success> ParseMemcgSwappiness(std::vector<std::string>&& args);
Result<Success> ParseNamespace(std::vector<std::string>&& args);
Result<Success> ParseProcessRlimit(std::vector<std::string>&& args);
Result<Success> ParseRestartPeriod(std::vector<std::string>&& args);
Result<Success> ParseSeclabel(std::vector<std::string>&& args);
Result<Success> ParseSetenv(std::vector<std::string>&& args);
Result<Success> ParseShutdown(std::vector<std::string>&& args);
Result<Success> ParseSigstop(std::vector<std::string>&& args);
Result<Success> ParseSocket(std::vector<std::string>&& args);
Result<Success> ParseTimeoutPeriod(std::vector<std::string>&& args);
Result<Success> ParseFile(std::vector<std::string>&& args);
Result<Success> ParseUser(std::vector<std::string>&& args);
Result<Success> ParseWritepid(std::vector<std::string>&& args);
Result<Success> ParseUpdatable(std::vector<std::string>&& args);
template <typename T>
Result<Success> AddDescriptor(std::vector<std::string>&& args);
static unsigned long next_start_order_;
static bool is_exec_service_running_;
std::string name_;
std::set<std::string> classnames_;
std::string console_;
unsigned flags_;
pid_t pid_;
android::base::boot_clock::time_point time_started_; // time of last start
android::base::boot_clock::time_point time_crashed_; // first crash within inspection window
int crash_count_; // number of times crashed within window
uid_t uid_;
gid_t gid_;
std::vector<gid_t> supp_gids_;
CapSet capabilities_;
unsigned namespace_flags_;
// Pair of namespace type, path to namespace.
std::vector<std::pair<int, std::string>> namespaces_to_enter_;
std::string seclabel_;
std::vector<std::unique_ptr<DescriptorInfo>> descriptors_;
std::vector<std::pair<std::string, std::string>> environment_vars_;
Action onrestart_; // Commands to execute on restart.
std::vector<std::string> writepid_files_;
std::set<std::string> interfaces_; // e.g. some.package.foo@1.0::IBaz/instance-name
// keycodes for triggering this service via /dev/input/input*
std::vector<int> keycodes_;
IoSchedClass ioprio_class_;
int ioprio_pri_;
int priority_;
int oom_score_adjust_;
int swappiness_ = -1;
int soft_limit_in_bytes_ = -1;
int limit_in_bytes_ = -1;
int limit_percent_ = -1;
std::string limit_property_;
bool process_cgroup_empty_ = false;
bool override_ = false;
unsigned long start_order_;
std::vector<std::pair<int, rlimit>> rlimits_;
bool sigstop_ = false;
std::chrono::seconds restart_period_ = 5s;
std::optional<std::chrono::seconds> timeout_period_;
bool updatable_ = false;
std::vector<std::string> args_;
std::vector<std::function<void(const siginfo_t& siginfo)>> reap_callbacks_;
bool pre_apexd_ = false;
};
class ServiceList {
public:
static ServiceList& GetInstance();
// Exposed for testing
ServiceList();
void AddService(std::unique_ptr<Service> service);
void RemoveService(const Service& svc);
template <typename T, typename F = decltype(&Service::name)>
Service* FindService(T value, F function = &Service::name) const {
auto svc = std::find_if(services_.begin(), services_.end(),
[&function, &value](const std::unique_ptr<Service>& s) {
return std::invoke(function, s) == value;
});
if (svc != services_.end()) {
return svc->get();
}
return nullptr;
}
Service* FindInterface(const std::string& interface_name) {
for (const auto& svc : services_) {
if (svc->interfaces().count(interface_name) > 0) {
return svc.get();
}
}
return nullptr;
}
void DumpState() const;
auto begin() const { return services_.begin(); }
auto end() const { return services_.end(); }
const std::vector<std::unique_ptr<Service>>& services() const { return services_; }
const std::vector<Service*> services_in_shutdown_order() const;
void MarkServicesUpdate();
bool IsServicesUpdated() const { return services_update_finished_; }
void DelayService(const Service& service);
private:
std::vector<std::unique_ptr<Service>> services_;
bool services_update_finished_ = false;
std::vector<std::string> delayed_service_names_;
};
class ServiceParser : public SectionParser {
public:
ServiceParser(ServiceList* service_list, std::vector<Subcontext>* subcontexts)
: service_list_(service_list), subcontexts_(subcontexts), service_(nullptr) {}
Result<Success> ParseSection(std::vector<std::string>&& args, const std::string& filename,
int line) override;
Result<Success> ParseLineSection(std::vector<std::string>&& args, int line) override;
Result<Success> EndSection() override;
void EndFile() override { filename_ = ""; }
private:
bool IsValidName(const std::string& name) const;
ServiceList* service_list_;
std::vector<Subcontext>* subcontexts_;
std::unique_ptr<Service> service_;
std::string filename_;
};
} // namespace init
} // namespace android
#endif
Reference in a new issue View git blame Copy permalink