src/pam-module.c

   1 /*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
   2
   3 /***
   4   This file is part of systemd.
   5
   6   Copyright 2010 Lennart Poettering
   7
   8   systemd is free software; you can redistribute it and/or modify it
   9   under the terms of the GNU General Public License as published by
  10   the Free Software Foundation; either version 2 of the License, or
  11   (at your option) any later version.
  12
  13   systemd is distributed in the hope that it will be useful, but
  14   WITHOUT ANY WARRANTY; without even the implied warranty of
  15   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  16   General Public License for more details.
  17
  18   You should have received a copy of the GNU General Public License
  19   along with systemd; If not, see <http://www.gnu.org/licenses/>.
  20 ***/
  21
  22 #include <errno.h>
  23 #include <fcntl.h>
  24 #include <sys/file.h>
  25 #include <pwd.h>
  26 #include <endian.h>
  27
  28 #include <security/pam_modules.h>
  29 #include <security/_pam_macros.h>
  30 #include <security/pam_modutil.h>
  31 #include <security/pam_ext.h>
  32 #include <security/pam_misc.h>
  33
  34 #include "util.h"
  35 #include "cgroup-util.h"
  36 #include "macro.h"
  37 #include "sd-daemon.h"
  38 #include "strv.h"
  39
  40 static int parse_argv(pam_handle_t *handle,
  41                       int argc, const char **argv,
  42                       bool *create_session,
  43                       bool *kill_session,
  44                       bool *kill_user,
  45                       char ***controllers,
  46                       char ***reset_controllers,
  47                       char ***kill_only_users,
  48                       char ***kill_exclude_users) {
  49
  50         unsigned i;
  51         bool reset_controller_set = false;
  52         bool kill_exclude_users_set = false;
  53
  54         assert(argc >= 0);
  55         assert(argc == 0 || argv);
  56
  57         for (i = 0; i < (unsigned) argc; i++) {
  58                 int k;
  59
  60                 if (startswith(argv[i], "create-session=")) {
  61                         if ((k = parse_boolean(argv[i] + 15)) < 0) {
  62                                 pam_syslog(handle, LOG_ERR, "Failed to parse create-session= argument.");
  63                                 return k;
  64                         }
  65
  66                         if (create_session)
  67                                 *create_session = k;
  68
  69                 } else if (startswith(argv[i], "kill-session=")) {
  70                         if ((k = parse_boolean(argv[i] + 13)) < 0) {
  71                                 pam_syslog(handle, LOG_ERR, "Failed to parse kill-session= argument.");
  72                                 return k;
  73                         }
  74
  75                         if (kill_session)
  76                                 *kill_session = k;
  77
  78                 } else if (startswith(argv[i], "kill-user=")) {
  79                         if ((k = parse_boolean(argv[i] + 10)) < 0) {
  80                                 pam_syslog(handle, LOG_ERR, "Failed to parse kill-user= argument.");
  81                                 return k;
  82                         }
  83
  84                         if (kill_user)
  85                                 *kill_user = k;
  86
  87                 } else if (startswith(argv[i], "controllers=")) {
  88
  89                         if (controllers) {
  90                                 char **l;
  91
  92                                 if (!(l = strv_split(argv[i] + 12, ","))) {
  93                                         pam_syslog(handle, LOG_ERR, "Out of memory.");
  94                                         return -ENOMEM;
  95                                 }
  96
  97                                 strv_free(*controllers);
  98                                 *controllers = l;
  99                         }
 100
 101                 } else if (startswith(argv[i], "reset-controllers=")) {
 102
 103                         if (reset_controllers) {
 104                                 char **l;
 105
 106                                 if (!(l = strv_split(argv[i] + 18, ","))) {
 107                                         pam_syslog(handle, LOG_ERR, "Out of memory.");
 108                                         return -ENOMEM;
 109                                 }
 110
 111                                 strv_free(*reset_controllers);
 112                                 *reset_controllers = l;
 113                         }
 114
 115                         reset_controller_set = true;
 116
 117                 } else if (startswith(argv[i], "kill-only-users=")) {
 118
 119                         if (kill_only_users) {
 120                                 char **l;
 121
 122                                 if (!(l = strv_split(argv[i] + 16, ","))) {
 123                                         pam_syslog(handle, LOG_ERR, "Out of memory.");
 124                                         return -ENOMEM;
 125                                 }
 126
 127                                 strv_free(*kill_only_users);
 128                                 *kill_only_users = l;
 129                         }
 130
 131                 } else if (startswith(argv[i], "kill-exclude-users=")) {
 132
 133                         if (kill_exclude_users) {
 134                                 char **l;
 135
 136                                 if (!(l = strv_split(argv[i] + 19, ","))) {
 137                                         pam_syslog(handle, LOG_ERR, "Out of memory.");
 138                                         return -ENOMEM;
 139                                 }
 140
 141                                 strv_free(*kill_exclude_users);
 142                                 *kill_exclude_users = l;
 143                         }
 144
 145                         kill_exclude_users_set = true;
 146
 147                 } else {
 148                         pam_syslog(handle, LOG_ERR, "Unknown parameter '%s'.", argv[i]);
 149                         return -EINVAL;
 150                 }
 151         }
 152
 153         if (!reset_controller_set && reset_controllers) {
 154                 char **l;
 155
 156                 if (!(l = strv_new("cpu", NULL))) {
 157                         pam_syslog(handle, LOG_ERR, "Out of memory");
 158                         return -ENOMEM;
 159                 }
 160
 161                 *reset_controllers = l;
 162         }
 163
 164         if (controllers)
 165                 strv_remove(*controllers, "name=systemd");
 166
 167         if (reset_controllers)
 168                 strv_remove(*reset_controllers, "name=systemd");
 169
 170         if (kill_session && *kill_session && kill_user)
 171                 *kill_user = true;
 172
 173         if (!kill_exclude_users_set && kill_exclude_users) {
 174                 char **l;
 175
 176                 if (!(l = strv_new("root", NULL))) {
 177                         pam_syslog(handle, LOG_ERR, "Out of memory");
 178                         return -ENOMEM;
 179                 }
 180
 181                 *kill_exclude_users = l;
 182         }
 183
 184         return 0;
 185 }
 186
 187 static int open_file_and_lock(const char *fn) {
 188         int fd;
 189
 190         assert(fn);
 191
 192         if ((fd = open(fn, O_RDWR|O_CLOEXEC|O_NOCTTY|O_NOFOLLOW|O_CREAT, 0600)) < 0)
 193                 return -errno;
 194
 195         /* The BSD socket semantics are a lot nicer than those of
 196          * POSIX locks. Which is why we use flock() here. BSD locking
 197          * does not work across NFS which however is not needed here
 198          * as the filesystems in question should be local, and only
 199          * locally accessible, and most likely even tmpfs. */
 200
 201         if (flock(fd, LOCK_EX) < 0)
 202                 return -errno;
 203
 204         return fd;
 205 }
 206
 207 enum {
 208         SESSION_ID_AUDIT = 'a',
 209         SESSION_ID_COUNTER = 'c',
 210         SESSION_ID_RANDOM = 'r'
 211 };
 212
 213 static uint64_t get_session_id(int *mode) {
 214         char *s;
 215         int fd;
 216
 217         assert(mode);
 218
 219         /* First attempt: let's use the session ID of the audit
 220          * system, if it is available. */
 221         if (read_one_line_file("/proc/self/sessionid", &s) >= 0) {
 222                 uint32_t u;
 223                 int r;
 224
 225                 r = safe_atou32(s, &u);
 226                 free(s);
 227
 228                 if (r >= 0 && u != (uint32_t) -1 && u > 0) {
 229                         *mode = SESSION_ID_AUDIT;
 230                         return (uint64_t) u;
 231                 }
 232         }
 233
 234         /* Second attempt, use our own counter. */
 235         if ((fd = open_file_and_lock(RUNTIME_DIR "/user/.pam-systemd-session")) >= 0) {
 236                 uint64_t counter;
 237                 ssize_t r;
 238
 239                 /* We do a bit of endianess swapping here, just to be
 240                  * sure. /var should be machine specific anyway, and
 241                  * /var/run even mounted from tmpfs, so this
 242                  * byteswapping should really not be necessary. But
 243                  * then again, you never know, so let's avoid any
 244                  * risk. */
 245
 246                 if (loop_read(fd, &counter, sizeof(counter), false) != sizeof(counter))
 247                         counter = 1;
 248                 else
 249                         counter = le64toh(counter) + 1;
 250
 251                 if (lseek(fd, 0, SEEK_SET) == 0) {
 252                         uint64_t swapped = htole64(counter);
 253
 254                         r = loop_write(fd, &swapped, sizeof(swapped), false);
 255
 256                         if (r != sizeof(swapped))
 257                                 r = -EIO;
 258                 } else
 259                         r = -errno;
 260
 261                 close_nointr_nofail(fd);
 262
 263                 if (r >= 0) {
 264                         *mode = SESSION_ID_COUNTER;
 265                         return counter;
 266                 }
 267         }
 268
 269         *mode = SESSION_ID_RANDOM;
 270
 271         /* Last attempt, pick a random value */
 272         return (uint64_t) random_ull();
 273 }
 274 static int get_user_data(
 275                 pam_handle_t *handle,
 276                 const char **ret_username,
 277                 struct passwd **ret_pw) {
 278
 279         const char *username = NULL;
 280         struct passwd *pw = NULL;
 281         int r;
 282         bool have_loginuid = false;
 283         char *s;
 284
 285         assert(handle);
 286         assert(ret_username);
 287         assert(ret_pw);
 288
 289         if (read_one_line_file("/proc/self/loginuid", &s) >= 0) {
 290                 uint32_t u;
 291
 292                 r = safe_atou32(s, &u);
 293                 free(s);
 294
 295                 if (r >= 0 && u != (uint32_t) -1 && u > 0) {
 296                         have_loginuid = true;
 297                         pw = pam_modutil_getpwuid(handle, u);
 298                 }
 299         }
 300
 301         if (!have_loginuid) {
 302                 if ((r = pam_get_user(handle, &username, NULL)) != PAM_SUCCESS) {
 303                         pam_syslog(handle, LOG_ERR, "Failed to get user name.");
 304                         return r;
 305                 }
 306
 307                 if (!username || !*username) {
 308                         pam_syslog(handle, LOG_ERR, "User name not valid.");
 309                         return PAM_AUTH_ERR;
 310                 }
 311
 312                 pw = pam_modutil_getpwnam(handle, username);
 313         }
 314
 315         if (!pw) {
 316                 pam_syslog(handle, LOG_ERR, "Failed to get user data.");
 317                 return PAM_USER_UNKNOWN;
 318         }
 319
 320         *ret_pw = pw;
 321         *ret_username = username ? username : pw->pw_name;
 322
 323         return PAM_SUCCESS;
 324 }
 325
 326 static int create_user_group(
 327                 pam_handle_t *handle,
 328                 const char *controller,
 329                 const char *group,
 330                 struct passwd *pw,
 331                 bool attach,
 332                 bool remember) {
 333
 334         int r;
 335
 336         assert(handle);
 337         assert(group);
 338
 339         if (attach)
 340                 r = cg_create_and_attach(controller, group, 0);
 341         else
 342                 r = cg_create(controller, group);
 343
 344         if (r < 0) {
 345                 pam_syslog(handle, LOG_ERR, "Failed to create cgroup: %s", strerror(-r));
 346                 return PAM_SESSION_ERR;
 347         }
 348
 349         if (r > 0 && remember) {
 350                 /* Remember that it was us who created this group, and
 351                  * that hence we need to remove it too. This is a
 352                  * protection against removing the cgroup when run
 353                  * recursively. */
 354                 if ((r = pam_set_data(handle, "systemd.created", INT_TO_PTR(1), NULL)) != PAM_SUCCESS) {
 355                         pam_syslog(handle, LOG_ERR, "Failed to install created variable.");
 356                         return r;
 357                 }
 358         }
 359
 360         if ((r = cg_set_task_access(controller, group, 0644, pw->pw_uid, pw->pw_gid)) < 0 ||
 361             (r = cg_set_group_access(controller, group, 0755, pw->pw_uid, pw->pw_gid)) < 0) {
 362                 pam_syslog(handle, LOG_ERR, "Failed to change access modes: %s", strerror(-r));
 363                 return PAM_SESSION_ERR;
 364         }
 365
 366         return PAM_SUCCESS;
 367 }
 368
 369 static int reset_group(
 370                 pam_handle_t *handle,
 371                 const char *controller) {
 372
 373         int r;
 374
 375         assert(handle);
 376
 377         if ((r = cg_attach(controller, "/", 0)) < 0) {
 378                 pam_syslog(handle, LOG_ERR, "Failed to reset cgroup for controller %s: %s", controller, strerror(-r));
 379                 return PAM_SESSION_ERR;
 380         }
 381
 382         return PAM_SUCCESS;
 383 }
 384
 385 _public_ PAM_EXTERN int pam_sm_open_session(
 386                 pam_handle_t *handle,
 387                 int flags,
 388                 int argc, const char **argv) {
 389
 390         const char *username = NULL;
 391         struct passwd *pw;
 392         int r;
 393         char *buf = NULL;
 394         int lock_fd = -1;
 395         bool create_session = true;
 396         char **controllers = NULL, **reset_controllers = NULL, **c;
 397
 398         assert(handle);
 399
 400         /* pam_syslog(handle, LOG_DEBUG, "pam-systemd initializing"); */
 401
 402         /* Make this a NOP on non-systemd systems */
 403         if (sd_booted() <= 0)
 404                 return PAM_SUCCESS;
 405
 406         if (parse_argv(handle,
 407                        argc, argv,
 408                        &create_session, NULL, NULL,
 409                        &controllers, &reset_controllers,
 410                        NULL, NULL) < 0)
 411                 return PAM_SESSION_ERR;
 412
 413         if ((r = get_user_data(handle, &username, &pw)) != PAM_SUCCESS)
 414                 goto finish;
 415
 416         if (safe_mkdir(RUNTIME_DIR "/user", 0755, 0, 0) < 0) {
 417                 pam_syslog(handle, LOG_ERR, "Failed to create runtime directory: %m");
 418                 r = PAM_SYSTEM_ERR;
 419                 goto finish;
 420         }
 421
 422         if ((lock_fd = open_file_and_lock(RUNTIME_DIR "/user/.pam-systemd-lock")) < 0) {
 423                 pam_syslog(handle, LOG_ERR, "Failed to lock runtime directory: %m");
 424                 r = PAM_SYSTEM_ERR;
 425                 goto finish;
 426         }
 427
 428         /* Create /var/run/$USER */
 429         free(buf);
 430         if (asprintf(&buf, RUNTIME_DIR "/user/%s", username) < 0) {
 431                 r = PAM_BUF_ERR;
 432                 goto finish;
 433         }
 434
 435         if (safe_mkdir(buf, 0700, pw->pw_uid, pw->pw_gid) < 0) {
 436                 pam_syslog(handle, LOG_WARNING, "Failed to create runtime directory: %m");
 437                 r = PAM_SYSTEM_ERR;
 438                 goto finish;
 439         } else if ((r = pam_misc_setenv(handle, "XDG_RUNTIME_DIR", buf, 0)) != PAM_SUCCESS) {
 440                 pam_syslog(handle, LOG_ERR, "Failed to set runtime dir.");
 441                 goto finish;
 442         }
 443
 444         free(buf);
 445         buf = NULL;
 446
 447         if (create_session) {
 448                 const char *id;
 449
 450                 /* Reuse or create XDG session ID */
 451                 if (!(id = pam_getenv(handle, "XDG_SESSION_ID"))) {
 452                         int mode;
 453
 454                         if (asprintf(&buf, "%llux", (unsigned long long) get_session_id(&mode)) < 0) {
 455                                 r = PAM_BUF_ERR;
 456                                 goto finish;
 457                         }
 458
 459                         /* To avoid id clashes we add the session id
 460                          * source to our session ids. Note that the
 461                          * session id source might change during
 462                          * runtime, because a filesystem became
 463                          * writable or the system reconfigured. */
 464                         buf[strlen(buf)-1] =
 465                                 mode != SESSION_ID_AUDIT ? (char) mode : 0;
 466
 467                         if ((r = pam_misc_setenv(handle, "XDG_SESSION_ID", buf, 0)) != PAM_SUCCESS) {
 468                                 pam_syslog(handle, LOG_ERR, "Failed to set session id.");
 469                                 goto finish;
 470                         }
 471
 472                         if (!(id = pam_getenv(handle, "XDG_SESSION_ID"))) {
 473                                 pam_syslog(handle, LOG_ERR, "Failed to get session id.");
 474                                 r = PAM_SESSION_ERR;
 475                                 goto finish;
 476                         }
 477                 }
 478
 479                 r = asprintf(&buf, "/user/%s/%s", username, id);
 480         } else
 481                 r = asprintf(&buf, "/user/%s/master", username);
 482
 483         if (r < 0) {
 484                 r = PAM_BUF_ERR;
 485                 goto finish;
 486         }
 487
 488         pam_syslog(handle, LOG_INFO, "Moving new user session for %s into control group %s.", username, buf);
 489
 490         if ((r = create_user_group(handle, SYSTEMD_CGROUP_CONTROLLER, buf, pw, true, true)) != PAM_SUCCESS)
 491                 goto finish;
 492
 493         /* The additional controllers don't really matter, so we
 494          * ignore the return value */
 495         STRV_FOREACH(c, controllers)
 496                 create_user_group(handle, *c, buf, pw, true, false);
 497
 498         STRV_FOREACH(c, reset_controllers)
 499                 reset_group(handle, *c);
 500
 501         r = PAM_SUCCESS;
 502
 503 finish:
 504         free(buf);
 505
 506         if (lock_fd >= 0)
 507                 close_nointr_nofail(lock_fd);
 508
 509         strv_free(controllers);
 510         strv_free(reset_controllers);
 511
 512         return r;
 513 }
 514
 515 static int session_remains(pam_handle_t *handle, const char *user_path) {
 516         int r;
 517         bool remains = false;
 518         DIR *d;
 519         char *subgroup;
 520
 521         if ((r = cg_enumerate_subgroups(SYSTEMD_CGROUP_CONTROLLER, user_path, &d)) < 0)
 522                 return r;
 523
 524         while ((r = cg_read_subgroup(d, &subgroup)) > 0) {
 525
 526                 remains = !streq(subgroup, "master");
 527                 free(subgroup);
 528
 529                 if (remains)
 530                         break;
 531         }
 532
 533         closedir(d);
 534
 535         if (r < 0)
 536                 return r;
 537
 538         return !!remains;
 539 }
 540
 541 static bool check_user_lists(
 542                 pam_handle_t *handle,
 543                 uid_t uid,
 544                 char **kill_only_users,
 545                 char **kill_exclude_users) {
 546
 547         const char *name = NULL;
 548         char **l;
 549
 550         assert(handle);
 551
 552         if (uid == 0)
 553                 name = "root"; /* Avoid obvious NSS requests, to suppress network traffic */
 554         else {
 555                 struct passwd *pw;
 556
 557                 if ((pw = pam_modutil_getpwuid(handle, uid)))
 558                         name = pw->pw_name;
 559         }
 560
 561         STRV_FOREACH(l, kill_exclude_users) {
 562                 uint32_t id;
 563
 564                 if (safe_atou32(*l, &id) >= 0)
 565                         if ((uid_t) id == uid)
 566                                 return false;
 567
 568                 if (name && streq(name, *l))
 569                         return false;
 570         }
 571
 572         if (strv_isempty(kill_only_users))
 573                 return true;
 574
 575         STRV_FOREACH(l, kill_only_users) {
 576                 uint32_t id;
 577
 578                 if (safe_atou32(*l, &id) >= 0)
 579                         if ((uid_t) id == uid)
 580                                 return true;
 581
 582                 if (name && streq(name, *l))
 583                         return true;
 584         }
 585
 586         return false;
 587 }
 588
 589 _public_ PAM_EXTERN int pam_sm_close_session(
 590                 pam_handle_t *handle,
 591                 int flags,
 592                 int argc, const char **argv) {
 593
 594         const char *username = NULL;
 595         bool kill_session = false;
 596         bool kill_user = false;
 597         int lock_fd = -1, r;
 598         char *session_path = NULL, *nosession_path = NULL, *user_path = NULL;
 599         const char *id;
 600         struct passwd *pw;
 601         const void *created = NULL;
 602         char **controllers = NULL, **c, **kill_only_users = NULL, **kill_exclude_users = NULL;
 603
 604         assert(handle);
 605
 606         /* Make this a NOP on non-systemd systems */
 607         if (sd_booted() <= 0)
 608                 return PAM_SUCCESS;
 609
 610         if (parse_argv(handle,
 611                        argc, argv,
 612                        NULL, &kill_session, &kill_user,
 613                        &controllers, NULL,
 614                        &kill_only_users, &kill_exclude_users) < 0)
 615                 return PAM_SESSION_ERR;
 616
 617         if ((r = get_user_data(handle, &username, &pw)) != PAM_SUCCESS)
 618                 goto finish;
 619
 620         if ((lock_fd = open_file_and_lock(RUNTIME_DIR "/user/.pam-systemd-lock")) < 0) {
 621                 pam_syslog(handle, LOG_ERR, "Failed to lock runtime directory: %m");
 622                 r = PAM_SYSTEM_ERR;
 623                 goto finish;
 624         }
 625
 626         /* We are probably still in some session/user dir. Move ourselves out of the way as first step */
 627         if ((r = cg_attach(SYSTEMD_CGROUP_CONTROLLER, "/user", 0)) < 0)
 628                 pam_syslog(handle, LOG_ERR, "Failed to move us away: %s", strerror(-r));
 629
 630         STRV_FOREACH(c, controllers)
 631                 if ((r = cg_attach(*c, "/user", 0)) < 0)
 632                         pam_syslog(handle, LOG_ERR, "Failed to move us away in %s hierarchy: %s", *c, strerror(-r));
 633
 634         if (asprintf(&user_path, "/user/%s", username) < 0) {
 635                 r = PAM_BUF_ERR;
 636                 goto finish;
 637         }
 638
 639         pam_get_data(handle, "systemd.created", &created);
 640
 641         if ((id = pam_getenv(handle, "XDG_SESSION_ID")) && created) {
 642
 643                 if (asprintf(&session_path, "/user/%s/%s", username, id) < 0 ||
 644                     asprintf(&nosession_path, "/user/%s/master", username) < 0) {
 645                         r = PAM_BUF_ERR;
 646                         goto finish;
 647                 }
 648
 649                 if (kill_session && check_user_lists(handle, pw->pw_uid, kill_only_users, kill_exclude_users))  {
 650                         pam_syslog(handle, LOG_INFO, "Killing remaining processes of user session %s of %s.", id, username);
 651
 652                         /* Kill processes in session cgroup, and delete it */
 653                         if ((r = cg_kill_recursive_and_wait(SYSTEMD_CGROUP_CONTROLLER, session_path, true)) < 0)
 654                                 pam_syslog(handle, LOG_ERR, "Failed to kill session cgroup: %s", strerror(-r));
 655                 } else {
 656                         pam_syslog(handle, LOG_INFO, "Moving remaining processes of user session %s of %s into control group %s.", id, username, nosession_path);
 657
 658                         /* Migrate processes from session to user
 659                          * cgroup. First, try to create the user group
 660                          * in case it doesn't exist yet. Also, delete
 661                          * the session group. */
 662                         create_user_group(handle, SYSTEMD_CGROUP_CONTROLLER, nosession_path, pw, false, false);
 663
 664                         if ((r = cg_migrate_recursive(SYSTEMD_CGROUP_CONTROLLER, session_path, nosession_path, false, true)) < 0)
 665                                 pam_syslog(handle, LOG_ERR, "Failed to migrate session cgroup: %s", strerror(-r));
 666                 }
 667
 668                 STRV_FOREACH(c, controllers) {
 669                         create_user_group(handle, *c, nosession_path, pw, false, false);
 670
 671                         if ((r = cg_migrate_recursive(*c, session_path, nosession_path, false, true)) < 0)
 672                                 pam_syslog(handle, LOG_ERR, "Failed to migrate session cgroup in hierarchy %s: %s", *c, strerror(-r));
 673                 }
 674         }
 675
 676         /* GC user tree */
 677         cg_trim(SYSTEMD_CGROUP_CONTROLLER, user_path, false);
 678
 679         if ((r = session_remains(handle, user_path)) < 0)
 680                 pam_syslog(handle, LOG_ERR, "Failed to determine whether a session remains: %s", strerror(-r));
 681
 682         /* Kill user processes not attached to any session */
 683         if (kill_user && r == 0 && check_user_lists(handle, pw->pw_uid, kill_only_users, kill_exclude_users)) {
 684
 685                 /* Kill user cgroup */
 686                 if ((r = cg_kill_recursive_and_wait(SYSTEMD_CGROUP_CONTROLLER, user_path, true)) < 0)
 687                         pam_syslog(handle, LOG_ERR, "Failed to kill user cgroup: %s", strerror(-r));
 688         } else {
 689
 690                 if ((r = cg_is_empty_recursive(SYSTEMD_CGROUP_CONTROLLER, user_path, true)) < 0)
 691                         pam_syslog(handle, LOG_ERR, "Failed to check user cgroup: %s", strerror(-r));
 692
 693                 /* Remove user cgroup */
 694                 if (r > 0) {
 695                         if ((r = cg_delete(SYSTEMD_CGROUP_CONTROLLER, user_path)) < 0)
 696                                 pam_syslog(handle, LOG_ERR, "Failed to delete user cgroup: %s", strerror(-r));
 697
 698                 /* If we managed to find somebody, don't cleanup the cgroup. */
 699                 } else if (r == 0)
 700                         r = -EBUSY;
 701         }
 702
 703         STRV_FOREACH(c, controllers)
 704                 cg_trim(*c, user_path, true);
 705
 706         if (r >= 0) {
 707                 const char *runtime_dir;
 708
 709                 if ((runtime_dir = pam_getenv(handle, "XDG_RUNTIME_DIR")))
 710                         if ((r = rm_rf(runtime_dir, false, true)) < 0)
 711                                 pam_syslog(handle, LOG_ERR, "Failed to remove runtime directory: %s", strerror(-r));
 712         }
 713
 714         /* pam_syslog(handle, LOG_DEBUG, "pam-systemd done"); */
 715
 716         r = PAM_SUCCESS;
 717
 718 finish:
 719         if (lock_fd >= 0)
 720                 close_nointr_nofail(lock_fd);
 721
 722         free(session_path);
 723         free(nosession_path);
 724         free(user_path);
 725
 726         strv_free(controllers);
 727         strv_free(kill_exclude_users);
 728         strv_free(kill_only_users);
 729
 730         return r;
 731 }