Colin Cross | cf8d1c2 | 2014-06-03 13:24:21 -0700 | [diff] [blame] | 1 | /* |
| 2 | * Copyright 2014 Google, Inc |
| 3 | * |
| 4 | * Licensed under the Apache License, Version 2.0 (the "License"); |
| 5 | * you may not use this file except in compliance with the License. |
| 6 | * You may obtain a copy of the License at |
| 7 | * |
| 8 | * http://www.apache.org/licenses/LICENSE-2.0 |
| 9 | * |
| 10 | * Unless required by applicable law or agreed to in writing, software |
| 11 | * distributed under the License is distributed on an "AS IS" BASIS, |
| 12 | * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| 13 | * See the License for the specific language governing permissions and |
| 14 | * limitations under the License. |
| 15 | */ |
| 16 | |
| 17 | //#define LOG_NDEBUG 0 |
| 18 | #define LOG_TAG "libprocessgroup" |
| 19 | |
| 20 | #include <assert.h> |
| 21 | #include <dirent.h> |
Elliott Hughes | 0badbd6 | 2014-12-29 12:24:25 -0800 | [diff] [blame] | 22 | #include <errno.h> |
Colin Cross | cf8d1c2 | 2014-06-03 13:24:21 -0700 | [diff] [blame] | 23 | #include <fcntl.h> |
Chih-Hung Hsieh | fcc8115 | 2014-11-20 17:05:15 -0800 | [diff] [blame] | 24 | #include <inttypes.h> |
Colin Cross | cf8d1c2 | 2014-06-03 13:24:21 -0700 | [diff] [blame] | 25 | #include <stdio.h> |
| 26 | #include <stdlib.h> |
| 27 | #include <string.h> |
| 28 | #include <sys/stat.h> |
| 29 | #include <sys/types.h> |
Tom Cherry | 70a5ed4 | 2017-06-05 19:20:17 -0700 | [diff] [blame^] | 30 | #include <unistd.h> |
Collin Mulliner | f7e79b9 | 2016-06-01 21:03:55 +0000 | [diff] [blame] | 31 | |
| 32 | #include <chrono> |
James Hawkins | 588a2ca | 2016-02-18 14:52:46 -0800 | [diff] [blame] | 33 | #include <memory> |
Elliott Hughes | 8d532e4 | 2016-06-06 21:19:55 -0700 | [diff] [blame] | 34 | #include <mutex> |
Tom Cherry | 70a5ed4 | 2017-06-05 19:20:17 -0700 | [diff] [blame^] | 35 | #include <set> |
Elliott Hughes | 290a228 | 2016-11-14 17:08:47 -0800 | [diff] [blame] | 36 | #include <thread> |
Colin Cross | cf8d1c2 | 2014-06-03 13:24:21 -0700 | [diff] [blame] | 37 | |
Elliott Hughes | 171df0a | 2016-08-02 13:30:30 -0700 | [diff] [blame] | 38 | #include <android-base/logging.h> |
Tom Cherry | 20514c4 | 2017-04-21 13:48:49 -0700 | [diff] [blame] | 39 | #include <android-base/unique_fd.h> |
Colin Cross | cf8d1c2 | 2014-06-03 13:24:21 -0700 | [diff] [blame] | 40 | #include <private/android_filesystem_config.h> |
| 41 | |
| 42 | #include <processgroup/processgroup.h> |
Martijn Coenen | b82bab6 | 2016-01-20 16:39:16 -0800 | [diff] [blame] | 43 | |
Elliott Hughes | 290a228 | 2016-11-14 17:08:47 -0800 | [diff] [blame] | 44 | using namespace std::chrono_literals; |
| 45 | |
Martijn Coenen | 5bb91ab | 2016-03-18 15:28:31 +0100 | [diff] [blame] | 46 | // Uncomment line below use memory cgroups for keeping track of (forked) PIDs |
| 47 | // #define USE_MEMCG 1 |
| 48 | |
Martijn Coenen | b82bab6 | 2016-01-20 16:39:16 -0800 | [diff] [blame] | 49 | #define MEM_CGROUP_PATH "/dev/memcg/apps" |
Martijn Coenen | 623b56a | 2016-02-08 11:42:25 +0100 | [diff] [blame] | 50 | #define MEM_CGROUP_TASKS "/dev/memcg/apps/tasks" |
Martijn Coenen | b82bab6 | 2016-01-20 16:39:16 -0800 | [diff] [blame] | 51 | #define ACCT_CGROUP_PATH "/acct" |
| 52 | |
| 53 | #define PROCESSGROUP_UID_PREFIX "uid_" |
| 54 | #define PROCESSGROUP_PID_PREFIX "pid_" |
| 55 | #define PROCESSGROUP_CGROUP_PROCS_FILE "/cgroup.procs" |
| 56 | #define PROCESSGROUP_MAX_UID_LEN 11 |
| 57 | #define PROCESSGROUP_MAX_PID_LEN 11 |
| 58 | #define PROCESSGROUP_MAX_PATH_LEN \ |
| 59 | ((sizeof(MEM_CGROUP_PATH) > sizeof(ACCT_CGROUP_PATH) ? \ |
| 60 | sizeof(MEM_CGROUP_PATH) : sizeof(ACCT_CGROUP_PATH)) + \ |
| 61 | sizeof(PROCESSGROUP_UID_PREFIX) + 1 + \ |
| 62 | PROCESSGROUP_MAX_UID_LEN + \ |
| 63 | sizeof(PROCESSGROUP_PID_PREFIX) + 1 + \ |
| 64 | PROCESSGROUP_MAX_PID_LEN + \ |
| 65 | sizeof(PROCESSGROUP_CGROUP_PROCS_FILE) + \ |
| 66 | 1) |
| 67 | |
| 68 | std::once_flag init_path_flag; |
Colin Cross | cf8d1c2 | 2014-06-03 13:24:21 -0700 | [diff] [blame] | 69 | |
Tom Cherry | 20514c4 | 2017-04-21 13:48:49 -0700 | [diff] [blame] | 70 | class ProcessGroup { |
| 71 | public: |
| 72 | ProcessGroup() : buf_ptr_(buf_), buf_len_(0) {} |
| 73 | |
| 74 | bool Open(uid_t uid, int pid); |
| 75 | |
| 76 | // Return positive number and sets *pid = next pid in process cgroup on success |
| 77 | // Returns 0 if there are no pids left in the process cgroup |
| 78 | // Returns -errno if an error was encountered |
| 79 | int GetOneAppProcess(pid_t* pid); |
| 80 | |
| 81 | private: |
| 82 | // Returns positive number of bytes filled on success |
| 83 | // Returns 0 if there was nothing to read |
| 84 | // Returns -errno if an error was encountered |
| 85 | int RefillBuffer(); |
| 86 | |
| 87 | android::base::unique_fd fd_; |
| 88 | char buf_[128]; |
| 89 | char* buf_ptr_; |
| 90 | size_t buf_len_; |
Colin Cross | cf8d1c2 | 2014-06-03 13:24:21 -0700 | [diff] [blame] | 91 | }; |
| 92 | |
Martijn Coenen | b82bab6 | 2016-01-20 16:39:16 -0800 | [diff] [blame] | 93 | static const char* getCgroupRootPath() { |
Martijn Coenen | 5bb91ab | 2016-03-18 15:28:31 +0100 | [diff] [blame] | 94 | #ifdef USE_MEMCG |
Martijn Coenen | b82bab6 | 2016-01-20 16:39:16 -0800 | [diff] [blame] | 95 | static const char* cgroup_root_path = NULL; |
| 96 | std::call_once(init_path_flag, [&]() { |
Martijn Coenen | 623b56a | 2016-02-08 11:42:25 +0100 | [diff] [blame] | 97 | // Check if mem cgroup is mounted, only then check for write-access to avoid |
| 98 | // SELinux denials |
| 99 | cgroup_root_path = access(MEM_CGROUP_TASKS, F_OK) || access(MEM_CGROUP_PATH, W_OK) ? |
| 100 | ACCT_CGROUP_PATH : MEM_CGROUP_PATH; |
Martijn Coenen | b82bab6 | 2016-01-20 16:39:16 -0800 | [diff] [blame] | 101 | }); |
| 102 | return cgroup_root_path; |
Martijn Coenen | 5bb91ab | 2016-03-18 15:28:31 +0100 | [diff] [blame] | 103 | #else |
| 104 | return ACCT_CGROUP_PATH; |
| 105 | #endif |
Martijn Coenen | b82bab6 | 2016-01-20 16:39:16 -0800 | [diff] [blame] | 106 | } |
| 107 | |
Colin Cross | cf8d1c2 | 2014-06-03 13:24:21 -0700 | [diff] [blame] | 108 | static int convertUidToPath(char *path, size_t size, uid_t uid) |
| 109 | { |
| 110 | return snprintf(path, size, "%s/%s%d", |
Martijn Coenen | b82bab6 | 2016-01-20 16:39:16 -0800 | [diff] [blame] | 111 | getCgroupRootPath(), |
Colin Cross | cf8d1c2 | 2014-06-03 13:24:21 -0700 | [diff] [blame] | 112 | PROCESSGROUP_UID_PREFIX, |
| 113 | uid); |
| 114 | } |
| 115 | |
| 116 | static int convertUidPidToPath(char *path, size_t size, uid_t uid, int pid) |
| 117 | { |
| 118 | return snprintf(path, size, "%s/%s%d/%s%d", |
Martijn Coenen | b82bab6 | 2016-01-20 16:39:16 -0800 | [diff] [blame] | 119 | getCgroupRootPath(), |
Colin Cross | cf8d1c2 | 2014-06-03 13:24:21 -0700 | [diff] [blame] | 120 | PROCESSGROUP_UID_PREFIX, |
| 121 | uid, |
| 122 | PROCESSGROUP_PID_PREFIX, |
| 123 | pid); |
| 124 | } |
| 125 | |
Tom Cherry | 20514c4 | 2017-04-21 13:48:49 -0700 | [diff] [blame] | 126 | bool ProcessGroup::Open(uid_t uid, int pid) { |
Colin Cross | cf8d1c2 | 2014-06-03 13:24:21 -0700 | [diff] [blame] | 127 | char path[PROCESSGROUP_MAX_PATH_LEN] = {0}; |
| 128 | convertUidPidToPath(path, sizeof(path), uid, pid); |
| 129 | strlcat(path, PROCESSGROUP_CGROUP_PROCS_FILE, sizeof(path)); |
| 130 | |
| 131 | int fd = open(path, O_RDONLY); |
Tom Cherry | 20514c4 | 2017-04-21 13:48:49 -0700 | [diff] [blame] | 132 | if (fd < 0) return false; |
Colin Cross | cf8d1c2 | 2014-06-03 13:24:21 -0700 | [diff] [blame] | 133 | |
Tom Cherry | 20514c4 | 2017-04-21 13:48:49 -0700 | [diff] [blame] | 134 | fd_.reset(fd); |
Colin Cross | cf8d1c2 | 2014-06-03 13:24:21 -0700 | [diff] [blame] | 135 | |
Elliott Hughes | 171df0a | 2016-08-02 13:30:30 -0700 | [diff] [blame] | 136 | LOG(VERBOSE) << "Initialized context for " << path; |
Dianne Hackborn | 2c5e7e1 | 2014-10-13 17:45:22 -0700 | [diff] [blame] | 137 | |
Tom Cherry | 20514c4 | 2017-04-21 13:48:49 -0700 | [diff] [blame] | 138 | return true; |
Colin Cross | cf8d1c2 | 2014-06-03 13:24:21 -0700 | [diff] [blame] | 139 | } |
| 140 | |
Tom Cherry | 20514c4 | 2017-04-21 13:48:49 -0700 | [diff] [blame] | 141 | int ProcessGroup::RefillBuffer() { |
| 142 | memmove(buf_, buf_ptr_, buf_len_); |
| 143 | buf_ptr_ = buf_; |
Colin Cross | cf8d1c2 | 2014-06-03 13:24:21 -0700 | [diff] [blame] | 144 | |
Tom Cherry | 20514c4 | 2017-04-21 13:48:49 -0700 | [diff] [blame] | 145 | ssize_t ret = read(fd_, buf_ptr_ + buf_len_, sizeof(buf_) - buf_len_ - 1); |
Colin Cross | cf8d1c2 | 2014-06-03 13:24:21 -0700 | [diff] [blame] | 146 | if (ret < 0) { |
| 147 | return -errno; |
| 148 | } else if (ret == 0) { |
| 149 | return 0; |
| 150 | } |
| 151 | |
Tom Cherry | 20514c4 | 2017-04-21 13:48:49 -0700 | [diff] [blame] | 152 | buf_len_ += ret; |
| 153 | buf_[buf_len_] = 0; |
| 154 | LOG(VERBOSE) << "Read " << ret << " to buffer: " << buf_; |
Dianne Hackborn | 2c5e7e1 | 2014-10-13 17:45:22 -0700 | [diff] [blame] | 155 | |
Tom Cherry | 20514c4 | 2017-04-21 13:48:49 -0700 | [diff] [blame] | 156 | assert(buf_len_ <= sizeof(buf_)); |
Colin Cross | cf8d1c2 | 2014-06-03 13:24:21 -0700 | [diff] [blame] | 157 | |
| 158 | return ret; |
| 159 | } |
| 160 | |
Tom Cherry | 20514c4 | 2017-04-21 13:48:49 -0700 | [diff] [blame] | 161 | int ProcessGroup::GetOneAppProcess(pid_t* out_pid) { |
| 162 | *out_pid = 0; |
Colin Cross | cf8d1c2 | 2014-06-03 13:24:21 -0700 | [diff] [blame] | 163 | |
Tom Cherry | 20514c4 | 2017-04-21 13:48:49 -0700 | [diff] [blame] | 164 | char* eptr; |
| 165 | while ((eptr = static_cast<char*>(memchr(buf_ptr_, '\n', buf_len_))) == nullptr) { |
| 166 | int ret = RefillBuffer(); |
| 167 | if (ret <= 0) return ret; |
Colin Cross | cf8d1c2 | 2014-06-03 13:24:21 -0700 | [diff] [blame] | 168 | } |
| 169 | |
| 170 | *eptr = '\0'; |
Tom Cherry | 20514c4 | 2017-04-21 13:48:49 -0700 | [diff] [blame] | 171 | char* pid_eptr = nullptr; |
Colin Cross | cf8d1c2 | 2014-06-03 13:24:21 -0700 | [diff] [blame] | 172 | errno = 0; |
Tom Cherry | 20514c4 | 2017-04-21 13:48:49 -0700 | [diff] [blame] | 173 | long pid = strtol(buf_ptr_, &pid_eptr, 10); |
Colin Cross | cf8d1c2 | 2014-06-03 13:24:21 -0700 | [diff] [blame] | 174 | if (errno != 0) { |
| 175 | return -errno; |
| 176 | } |
| 177 | if (pid_eptr != eptr) { |
Tom Cherry | 20514c4 | 2017-04-21 13:48:49 -0700 | [diff] [blame] | 178 | errno = EINVAL; |
| 179 | return -errno; |
Colin Cross | cf8d1c2 | 2014-06-03 13:24:21 -0700 | [diff] [blame] | 180 | } |
| 181 | |
Tom Cherry | 20514c4 | 2017-04-21 13:48:49 -0700 | [diff] [blame] | 182 | buf_len_ -= (eptr - buf_ptr_) + 1; |
| 183 | buf_ptr_ = eptr + 1; |
Colin Cross | cf8d1c2 | 2014-06-03 13:24:21 -0700 | [diff] [blame] | 184 | |
Tom Cherry | 20514c4 | 2017-04-21 13:48:49 -0700 | [diff] [blame] | 185 | *out_pid = static_cast<pid_t>(pid); |
| 186 | return 1; |
Colin Cross | cf8d1c2 | 2014-06-03 13:24:21 -0700 | [diff] [blame] | 187 | } |
| 188 | |
| 189 | static int removeProcessGroup(uid_t uid, int pid) |
| 190 | { |
| 191 | int ret; |
| 192 | char path[PROCESSGROUP_MAX_PATH_LEN] = {0}; |
| 193 | |
| 194 | convertUidPidToPath(path, sizeof(path), uid, pid); |
| 195 | ret = rmdir(path); |
| 196 | |
| 197 | convertUidToPath(path, sizeof(path), uid); |
| 198 | rmdir(path); |
| 199 | |
| 200 | return ret; |
| 201 | } |
| 202 | |
| 203 | static void removeUidProcessGroups(const char *uid_path) |
| 204 | { |
James Hawkins | 588a2ca | 2016-02-18 14:52:46 -0800 | [diff] [blame] | 205 | std::unique_ptr<DIR, decltype(&closedir)> uid(opendir(uid_path), closedir); |
Colin Cross | cf8d1c2 | 2014-06-03 13:24:21 -0700 | [diff] [blame] | 206 | if (uid != NULL) { |
Elliott Hughes | 9f20693 | 2016-09-28 13:29:54 -0700 | [diff] [blame] | 207 | dirent* dir; |
| 208 | while ((dir = readdir(uid.get())) != nullptr) { |
Colin Cross | cf8d1c2 | 2014-06-03 13:24:21 -0700 | [diff] [blame] | 209 | char path[PROCESSGROUP_MAX_PATH_LEN]; |
| 210 | |
| 211 | if (dir->d_type != DT_DIR) { |
| 212 | continue; |
| 213 | } |
| 214 | |
| 215 | if (strncmp(dir->d_name, PROCESSGROUP_PID_PREFIX, strlen(PROCESSGROUP_PID_PREFIX))) { |
| 216 | continue; |
| 217 | } |
| 218 | |
| 219 | snprintf(path, sizeof(path), "%s/%s", uid_path, dir->d_name); |
Tom Cherry | 20514c4 | 2017-04-21 13:48:49 -0700 | [diff] [blame] | 220 | LOG(VERBOSE) << "Removing " << path; |
| 221 | if (rmdir(path) == -1) PLOG(WARNING) << "Failed to remove " << path; |
Colin Cross | cf8d1c2 | 2014-06-03 13:24:21 -0700 | [diff] [blame] | 222 | } |
| 223 | } |
| 224 | } |
| 225 | |
| 226 | void removeAllProcessGroups() |
| 227 | { |
Elliott Hughes | 171df0a | 2016-08-02 13:30:30 -0700 | [diff] [blame] | 228 | LOG(VERBOSE) << "removeAllProcessGroups()"; |
Elliott Hughes | b6e1d15 | 2016-08-03 13:29:04 -0700 | [diff] [blame] | 229 | const char* cgroup_root_path = getCgroupRootPath(); |
James Hawkins | 22b6f7a | 2016-02-19 11:10:30 -0800 | [diff] [blame] | 230 | std::unique_ptr<DIR, decltype(&closedir)> root(opendir(cgroup_root_path), closedir); |
Colin Cross | cf8d1c2 | 2014-06-03 13:24:21 -0700 | [diff] [blame] | 231 | if (root == NULL) { |
Tom Cherry | 20514c4 | 2017-04-21 13:48:49 -0700 | [diff] [blame] | 232 | PLOG(ERROR) << "Failed to open " << cgroup_root_path; |
Colin Cross | c15dd04 | 2014-08-20 14:11:13 -0700 | [diff] [blame] | 233 | } else { |
Elliott Hughes | 9f20693 | 2016-09-28 13:29:54 -0700 | [diff] [blame] | 234 | dirent* dir; |
| 235 | while ((dir = readdir(root.get())) != nullptr) { |
Colin Cross | cf8d1c2 | 2014-06-03 13:24:21 -0700 | [diff] [blame] | 236 | char path[PROCESSGROUP_MAX_PATH_LEN]; |
| 237 | |
| 238 | if (dir->d_type != DT_DIR) { |
| 239 | continue; |
| 240 | } |
| 241 | if (strncmp(dir->d_name, PROCESSGROUP_UID_PREFIX, strlen(PROCESSGROUP_UID_PREFIX))) { |
| 242 | continue; |
| 243 | } |
| 244 | |
Martijn Coenen | b82bab6 | 2016-01-20 16:39:16 -0800 | [diff] [blame] | 245 | snprintf(path, sizeof(path), "%s/%s", cgroup_root_path, dir->d_name); |
Colin Cross | cf8d1c2 | 2014-06-03 13:24:21 -0700 | [diff] [blame] | 246 | removeUidProcessGroups(path); |
Tom Cherry | 20514c4 | 2017-04-21 13:48:49 -0700 | [diff] [blame] | 247 | LOG(VERBOSE) << "Removing " << path; |
| 248 | if (rmdir(path) == -1) PLOG(WARNING) << "Failed to remove " << path; |
Colin Cross | cf8d1c2 | 2014-06-03 13:24:21 -0700 | [diff] [blame] | 249 | } |
Colin Cross | cf8d1c2 | 2014-06-03 13:24:21 -0700 | [diff] [blame] | 250 | } |
| 251 | } |
| 252 | |
Tom Cherry | 20514c4 | 2017-04-21 13:48:49 -0700 | [diff] [blame] | 253 | // Returns number of processes killed on success |
| 254 | // Returns 0 if there are no processes in the process cgroup left to kill |
| 255 | // Returns -errno on error |
Keun-young Park | fac4b63 | 2017-03-28 17:25:24 -0700 | [diff] [blame] | 256 | static int doKillProcessGroupOnce(uid_t uid, int initialPid, int signal) { |
Tom Cherry | 20514c4 | 2017-04-21 13:48:49 -0700 | [diff] [blame] | 257 | ProcessGroup process_group; |
| 258 | if (!process_group.Open(uid, initialPid)) { |
| 259 | PLOG(WARNING) << "Failed to open process cgroup uid " << uid << " pid " << initialPid; |
| 260 | return -errno; |
| 261 | } |
| 262 | |
Tom Cherry | 70a5ed4 | 2017-06-05 19:20:17 -0700 | [diff] [blame^] | 263 | // We separate all of the pids in the cgroup into those pids that are also the leaders of |
| 264 | // process groups (stored in the pgids set) and those that are not (stored in the pids set). |
| 265 | std::set<pid_t> pgids; |
| 266 | pgids.emplace(initialPid); |
| 267 | std::set<pid_t> pids; |
| 268 | |
Tom Cherry | 20514c4 | 2017-04-21 13:48:49 -0700 | [diff] [blame] | 269 | int ret; |
Colin Cross | cf8d1c2 | 2014-06-03 13:24:21 -0700 | [diff] [blame] | 270 | pid_t pid; |
Tom Cherry | 20514c4 | 2017-04-21 13:48:49 -0700 | [diff] [blame] | 271 | int processes = 0; |
| 272 | while ((ret = process_group.GetOneAppProcess(&pid)) > 0 && pid >= 0) { |
Colin Cross | cf8d1c2 | 2014-06-03 13:24:21 -0700 | [diff] [blame] | 273 | processes++; |
Dianne Hackborn | 2c5e7e1 | 2014-10-13 17:45:22 -0700 | [diff] [blame] | 274 | if (pid == 0) { |
| 275 | // Should never happen... but if it does, trying to kill this |
| 276 | // will boomerang right back and kill us! Let's not let that happen. |
Elliott Hughes | 171df0a | 2016-08-02 13:30:30 -0700 | [diff] [blame] | 277 | LOG(WARNING) << "Yikes, we've been told to kill pid 0! How about we don't do that?"; |
Dianne Hackborn | 2c5e7e1 | 2014-10-13 17:45:22 -0700 | [diff] [blame] | 278 | continue; |
| 279 | } |
Tom Cherry | 70a5ed4 | 2017-06-05 19:20:17 -0700 | [diff] [blame^] | 280 | pid_t pgid = getpgid(pid); |
| 281 | if (pgid == -1) PLOG(ERROR) << "getpgid(" << pid << ") failed"; |
| 282 | if (pgid == pid) { |
| 283 | pgids.emplace(pid); |
| 284 | } else { |
| 285 | pids.emplace(pid); |
| 286 | } |
| 287 | } |
| 288 | |
| 289 | // Erase all pids that will be killed when we kill the process groups. |
| 290 | for (auto it = pids.begin(); it != pids.end();) { |
| 291 | pid_t pgid = getpgid(pid); |
| 292 | if (pgids.count(pgid) == 1) { |
| 293 | it = pids.erase(it); |
| 294 | } else { |
| 295 | ++it; |
| 296 | } |
| 297 | } |
| 298 | |
| 299 | // Kill all process groups. |
| 300 | for (const auto pgid : pgids) { |
| 301 | LOG(VERBOSE) << "Killing process group " << -pgid << " in uid " << uid |
| 302 | << " as part of process cgroup " << initialPid; |
| 303 | |
| 304 | if (kill(-pgid, signal) == -1) { |
| 305 | PLOG(WARNING) << "kill(" << -pgid << ", " << signal << ") failed"; |
| 306 | } |
| 307 | } |
| 308 | |
| 309 | // Kill remaining pids. |
| 310 | for (const auto pid : pids) { |
Tom Cherry | 20514c4 | 2017-04-21 13:48:49 -0700 | [diff] [blame] | 311 | LOG(VERBOSE) << "Killing pid " << pid << " in uid " << uid << " as part of process cgroup " |
| 312 | << initialPid; |
Tom Cherry | 70a5ed4 | 2017-06-05 19:20:17 -0700 | [diff] [blame^] | 313 | |
Elliott Hughes | 171df0a | 2016-08-02 13:30:30 -0700 | [diff] [blame] | 314 | if (kill(pid, signal) == -1) { |
| 315 | PLOG(WARNING) << "kill(" << pid << ", " << signal << ") failed"; |
Colin Cross | cf8d1c2 | 2014-06-03 13:24:21 -0700 | [diff] [blame] | 316 | } |
| 317 | } |
| 318 | |
Tom Cherry | 20514c4 | 2017-04-21 13:48:49 -0700 | [diff] [blame] | 319 | return ret >= 0 ? processes : ret; |
Colin Cross | cf8d1c2 | 2014-06-03 13:24:21 -0700 | [diff] [blame] | 320 | } |
| 321 | |
Tom Cherry | 20514c4 | 2017-04-21 13:48:49 -0700 | [diff] [blame] | 322 | static int killProcessGroup(uid_t uid, int initialPid, int signal, int retries) { |
Collin Mulliner | f7e79b9 | 2016-06-01 21:03:55 +0000 | [diff] [blame] | 323 | std::chrono::steady_clock::time_point start = std::chrono::steady_clock::now(); |
Colin Cross | cf8d1c2 | 2014-06-03 13:24:21 -0700 | [diff] [blame] | 324 | |
Tom Cherry | 20514c4 | 2017-04-21 13:48:49 -0700 | [diff] [blame] | 325 | int retry = retries; |
Collin Mulliner | f7e79b9 | 2016-06-01 21:03:55 +0000 | [diff] [blame] | 326 | int processes; |
Keun-young Park | fac4b63 | 2017-03-28 17:25:24 -0700 | [diff] [blame] | 327 | while ((processes = doKillProcessGroupOnce(uid, initialPid, signal)) > 0) { |
Tom Cherry | 20514c4 | 2017-04-21 13:48:49 -0700 | [diff] [blame] | 328 | LOG(VERBOSE) << "Killed " << processes << " processes for processgroup " << initialPid; |
Yusuke Sato | d503930 | 2015-06-16 13:51:14 -0700 | [diff] [blame] | 329 | if (retry > 0) { |
Elliott Hughes | 290a228 | 2016-11-14 17:08:47 -0800 | [diff] [blame] | 330 | std::this_thread::sleep_for(5ms); |
Yusuke Sato | d503930 | 2015-06-16 13:51:14 -0700 | [diff] [blame] | 331 | --retry; |
Colin Cross | cf8d1c2 | 2014-06-03 13:24:21 -0700 | [diff] [blame] | 332 | } else { |
Colin Cross | cf8d1c2 | 2014-06-03 13:24:21 -0700 | [diff] [blame] | 333 | break; |
| 334 | } |
| 335 | } |
| 336 | |
Tom Cherry | 20514c4 | 2017-04-21 13:48:49 -0700 | [diff] [blame] | 337 | if (processes < 0) { |
| 338 | PLOG(ERROR) << "Error encountered killing process cgroup uid " << uid << " pid " |
| 339 | << initialPid; |
| 340 | return -1; |
| 341 | } |
Collin Mulliner | f7e79b9 | 2016-06-01 21:03:55 +0000 | [diff] [blame] | 342 | |
Tom Cherry | 20514c4 | 2017-04-21 13:48:49 -0700 | [diff] [blame] | 343 | std::chrono::steady_clock::time_point end = std::chrono::steady_clock::now(); |
Elliott Hughes | 171df0a | 2016-08-02 13:30:30 -0700 | [diff] [blame] | 344 | auto ms = std::chrono::duration_cast<std::chrono::milliseconds>(end - start).count(); |
Tom Cherry | 20514c4 | 2017-04-21 13:48:49 -0700 | [diff] [blame] | 345 | |
| 346 | // We only calculate the number of 'processes' when killing the processes. |
| 347 | // In the retries == 0 case, we only kill the processes once and therefore |
| 348 | // will not have waited then recalculated how many processes are remaining |
| 349 | // after the first signals have been sent. |
| 350 | // Logging anything regarding the number of 'processes' here does not make sense. |
Dianne Hackborn | 2c5e7e1 | 2014-10-13 17:45:22 -0700 | [diff] [blame] | 351 | |
Colin Cross | cf8d1c2 | 2014-06-03 13:24:21 -0700 | [diff] [blame] | 352 | if (processes == 0) { |
Tom Cherry | 20514c4 | 2017-04-21 13:48:49 -0700 | [diff] [blame] | 353 | if (retries > 0) { |
| 354 | LOG(INFO) << "Successfully killed process cgroup uid " << uid << " pid " << initialPid |
| 355 | << " in " << static_cast<int>(ms) << "ms"; |
| 356 | } |
Colin Cross | cf8d1c2 | 2014-06-03 13:24:21 -0700 | [diff] [blame] | 357 | return removeProcessGroup(uid, initialPid); |
| 358 | } else { |
Tom Cherry | 20514c4 | 2017-04-21 13:48:49 -0700 | [diff] [blame] | 359 | if (retries > 0) { |
| 360 | LOG(ERROR) << "Failed to kill process cgroup uid " << uid << " pid " << initialPid |
| 361 | << " in " << static_cast<int>(ms) << "ms, " << processes |
| 362 | << " processes remain"; |
| 363 | } |
Colin Cross | cf8d1c2 | 2014-06-03 13:24:21 -0700 | [diff] [blame] | 364 | return -1; |
| 365 | } |
| 366 | } |
| 367 | |
Keun-young Park | fac4b63 | 2017-03-28 17:25:24 -0700 | [diff] [blame] | 368 | int killProcessGroup(uid_t uid, int initialPid, int signal) { |
Tom Cherry | 20514c4 | 2017-04-21 13:48:49 -0700 | [diff] [blame] | 369 | return killProcessGroup(uid, initialPid, signal, 40 /*retries*/); |
Keun-young Park | fac4b63 | 2017-03-28 17:25:24 -0700 | [diff] [blame] | 370 | } |
| 371 | |
| 372 | int killProcessGroupOnce(uid_t uid, int initialPid, int signal) { |
Tom Cherry | 20514c4 | 2017-04-21 13:48:49 -0700 | [diff] [blame] | 373 | return killProcessGroup(uid, initialPid, signal, 0 /*retries*/); |
Keun-young Park | fac4b63 | 2017-03-28 17:25:24 -0700 | [diff] [blame] | 374 | } |
| 375 | |
Elliott Hughes | 171df0a | 2016-08-02 13:30:30 -0700 | [diff] [blame] | 376 | static bool mkdirAndChown(const char *path, mode_t mode, uid_t uid, gid_t gid) |
Colin Cross | cf8d1c2 | 2014-06-03 13:24:21 -0700 | [diff] [blame] | 377 | { |
Elliott Hughes | 171df0a | 2016-08-02 13:30:30 -0700 | [diff] [blame] | 378 | if (mkdir(path, mode) == -1 && errno != EEXIST) { |
| 379 | return false; |
Colin Cross | cf8d1c2 | 2014-06-03 13:24:21 -0700 | [diff] [blame] | 380 | } |
| 381 | |
Elliott Hughes | 171df0a | 2016-08-02 13:30:30 -0700 | [diff] [blame] | 382 | if (chown(path, uid, gid) == -1) { |
| 383 | int saved_errno = errno; |
Colin Cross | cf8d1c2 | 2014-06-03 13:24:21 -0700 | [diff] [blame] | 384 | rmdir(path); |
Elliott Hughes | 171df0a | 2016-08-02 13:30:30 -0700 | [diff] [blame] | 385 | errno = saved_errno; |
| 386 | return false; |
Colin Cross | cf8d1c2 | 2014-06-03 13:24:21 -0700 | [diff] [blame] | 387 | } |
| 388 | |
Elliott Hughes | 171df0a | 2016-08-02 13:30:30 -0700 | [diff] [blame] | 389 | return true; |
Colin Cross | cf8d1c2 | 2014-06-03 13:24:21 -0700 | [diff] [blame] | 390 | } |
| 391 | |
| 392 | int createProcessGroup(uid_t uid, int initialPid) |
| 393 | { |
| 394 | char path[PROCESSGROUP_MAX_PATH_LEN] = {0}; |
Colin Cross | cf8d1c2 | 2014-06-03 13:24:21 -0700 | [diff] [blame] | 395 | |
| 396 | convertUidToPath(path, sizeof(path), uid); |
| 397 | |
Elliott Hughes | 171df0a | 2016-08-02 13:30:30 -0700 | [diff] [blame] | 398 | if (!mkdirAndChown(path, 0750, AID_SYSTEM, AID_SYSTEM)) { |
Tom Cherry | 20514c4 | 2017-04-21 13:48:49 -0700 | [diff] [blame] | 399 | PLOG(ERROR) << "Failed to make and chown " << path; |
Elliott Hughes | 171df0a | 2016-08-02 13:30:30 -0700 | [diff] [blame] | 400 | return -errno; |
Colin Cross | cf8d1c2 | 2014-06-03 13:24:21 -0700 | [diff] [blame] | 401 | } |
| 402 | |
| 403 | convertUidPidToPath(path, sizeof(path), uid, initialPid); |
| 404 | |
Elliott Hughes | 171df0a | 2016-08-02 13:30:30 -0700 | [diff] [blame] | 405 | if (!mkdirAndChown(path, 0750, AID_SYSTEM, AID_SYSTEM)) { |
Tom Cherry | 20514c4 | 2017-04-21 13:48:49 -0700 | [diff] [blame] | 406 | PLOG(ERROR) << "Failed to make and chown " << path; |
Elliott Hughes | 171df0a | 2016-08-02 13:30:30 -0700 | [diff] [blame] | 407 | return -errno; |
Colin Cross | cf8d1c2 | 2014-06-03 13:24:21 -0700 | [diff] [blame] | 408 | } |
| 409 | |
| 410 | strlcat(path, PROCESSGROUP_CGROUP_PROCS_FILE, sizeof(path)); |
| 411 | |
| 412 | int fd = open(path, O_WRONLY); |
Elliott Hughes | 171df0a | 2016-08-02 13:30:30 -0700 | [diff] [blame] | 413 | if (fd == -1) { |
| 414 | int ret = -errno; |
Tom Cherry | 20514c4 | 2017-04-21 13:48:49 -0700 | [diff] [blame] | 415 | PLOG(ERROR) << "Failed to open " << path; |
Colin Cross | cf8d1c2 | 2014-06-03 13:24:21 -0700 | [diff] [blame] | 416 | return ret; |
| 417 | } |
| 418 | |
| 419 | char pid[PROCESSGROUP_MAX_PID_LEN + 1] = {0}; |
| 420 | int len = snprintf(pid, sizeof(pid), "%d", initialPid); |
| 421 | |
Elliott Hughes | 171df0a | 2016-08-02 13:30:30 -0700 | [diff] [blame] | 422 | int ret = 0; |
| 423 | if (write(fd, pid, len) < 0) { |
Colin Cross | cf8d1c2 | 2014-06-03 13:24:21 -0700 | [diff] [blame] | 424 | ret = -errno; |
Tom Cherry | 20514c4 | 2017-04-21 13:48:49 -0700 | [diff] [blame] | 425 | PLOG(ERROR) << "Failed to write '" << pid << "' to " << path; |
Colin Cross | cf8d1c2 | 2014-06-03 13:24:21 -0700 | [diff] [blame] | 426 | } |
| 427 | |
| 428 | close(fd); |
| 429 | return ret; |
| 430 | } |