1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
|
//
// 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.
//
#include "shill/process_manager.h"
#include <signal.h>
#include <stdlib.h>
#include <sys/prctl.h>
#include "shill/event_dispatcher.h"
using base::Closure;
using std::map;
using std::string;
using std::vector;
namespace shill {
namespace {
base::LazyInstance<ProcessManager> g_process_manager =
LAZY_INSTANCE_INITIALIZER;
static const int kTerminationTimeoutSeconds = 2;
bool SetupChild(const map<string, string>& env, bool terminate_with_parent) {
// Setup environment variables.
clearenv();
for (const auto& key_value : env) {
setenv(key_value.first.c_str(), key_value.second.c_str(), 0);
}
if (terminate_with_parent) {
prctl(PR_SET_PDEATHSIG, SIGTERM);
}
return true;
}
} // namespace
ProcessManager::ProcessManager() {}
ProcessManager::~ProcessManager() {}
// static
ProcessManager* ProcessManager::GetInstance() {
return g_process_manager.Pointer();
}
void ProcessManager::Init(EventDispatcher* dispatcher) {
async_signal_handler_.Init();
process_reaper_.Register(&async_signal_handler_);
dispatcher_ = dispatcher;
minijail_ = chromeos::Minijail::GetInstance();
}
pid_t ProcessManager::StartProcess(
const tracked_objects::Location& from_here,
const base::FilePath& program,
const vector<string>& arguments,
const map<string, string>& environment,
bool terminate_with_parent,
const base::Callback<void(int)>& exit_callback) {
// Setup/create child process.
std::unique_ptr<chromeos::Process> process(new chromeos::ProcessImpl());
process->AddArg(program.value());
for (const auto& option : arguments) {
process->AddArg(option);
}
process->SetPreExecCallback(
base::Bind(&SetupChild, environment, terminate_with_parent));
if (!process->Start()) {
LOG(ERROR) << "Failed to start child process for " << program.value();
return -1;
}
// Setup watcher for the child process.
pid_t pid = process->pid();
CHECK(process_reaper_.WatchForChild(
from_here,
pid,
base::Bind(&ProcessManager::OnProcessExited,
weak_factory_.GetWeakPtr(),
pid)));
// Release ownership of the child process from the |process| object, so that
// child process will not get killed on destruction of |process| object.
process->Release();
watched_processes_.emplace(pid, exit_callback);
return pid;
}
pid_t ProcessManager::StartProcessInMinijail(
const tracked_objects::Location& from_here,
const base::FilePath& program,
const std::vector<std::string>& arguments,
const std::string& user,
const std::string& group,
uint64_t capmask,
const base::Callback<void(int)>& exit_callback) {
vector<char*> args;
args.push_back(const_cast<char*>(program.value().c_str()));
for (const auto& arg : arguments) {
args.push_back(const_cast<char*>(arg.c_str()));
}
args.push_back(nullptr);
struct minijail* jail = minijail_->New();
minijail_->DropRoot(jail, user.c_str(), group.c_str());
minijail_->UseCapabilities(jail, capmask);
pid_t pid;
if (!minijail_->RunAndDestroy(jail, args, &pid)) {
LOG(ERROR) << "Unable to spawn " << program.value() << " in a jail.";
return -1;
}
watched_processes_.emplace(pid, exit_callback);
return pid;
}
bool ProcessManager::StopProcess(pid_t pid) {
if (pending_termination_processes_.find(pid) !=
pending_termination_processes_.end()) {
LOG(ERROR) << "Process " << pid << " already being stopped.";
return false;
}
if (watched_processes_.find(pid) == watched_processes_.end()) {
LOG(ERROR) << "Process " << pid << " not being watched";
return false;
}
// Caller not interested in watching this process anymore, since the
// process termination is initiated by the caller.
watched_processes_.erase(pid);
// Attempt to send SIGTERM signal first.
return TerminateProcess(pid, false);
}
void ProcessManager::OnProcessExited(pid_t pid, const siginfo_t& info) {
// Invoke the exit callback if the process is being watched.
auto watched_process = watched_processes_.find(pid);
if (watched_process != watched_processes_.end()) {
base::Callback<void(int)> callback = watched_process->second;
watched_processes_.erase(watched_process);
callback.Run(info.si_status);
return;
}
// Process terminated by us, cancel timeout handler.
auto terminated_process = pending_termination_processes_.find(pid);
if (terminated_process != pending_termination_processes_.end()) {
terminated_process->second->Cancel();
pending_termination_processes_.erase(terminated_process);
return;
}
NOTREACHED() << "Unknown process " << pid << " status " << info.si_status;
}
void ProcessManager::ProcessTerminationTimeoutHandler(pid_t pid,
bool kill_signal) {
CHECK(pending_termination_processes_.find(pid) !=
pending_termination_processes_.end());
pending_termination_processes_.erase(pid);
// Process still not killed after SIGKILL signal.
if (kill_signal) {
LOG(ERROR) << "Timeout waiting for process to be killed.";
return;
}
// Retry using SIGKILL signal.
TerminateProcess(pid, true);
}
bool ProcessManager::TerminateProcess(pid_t pid, bool kill_signal) {
int signal = (kill_signal) ? SIGKILL : SIGTERM;
if (kill(pid, signal) < 0) {
PLOG(ERROR) << "Failed to send " << signal << " signal to process " << pid;
return false;
}
std::unique_ptr<TerminationTimeoutCallback> termination_callback(
new TerminationTimeoutCallback(
base::Bind(&ProcessManager::ProcessTerminationTimeoutHandler,
weak_factory_.GetWeakPtr(),
pid,
kill_signal)));
dispatcher_->PostDelayedTask(termination_callback->callback(),
kTerminationTimeoutSeconds * 1000);
pending_termination_processes_.emplace(pid, std::move(termination_callback));
return true;
}
} // namespace shill
|
