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                 int r = -errno;
 203
 204                 close_nointr_nofail(fd);
 205                 return r;
 206         }
 207
 208         return fd;
 209 }
 210
 211 enum {
 212         SESSION_ID_AUDIT = 'a',
 213         SESSION_ID_COUNTER = 'c',
 214         SESSION_ID_RANDOM = 'r'
 215 };
 216
 217 static uint64_t get_session_id(int *mode) {
 218         char *s;
 219         int fd;
 220
 221         assert(mode);
 222
 223         /* First attempt: let's use the session ID of the audit
 224          * system, if it is available. */
 225         if (read_one_line_file("/proc/self/sessionid", &s) >= 0) {
 226                 uint32_t u;
 227                 int r;
 228
 229                 r = safe_atou32(s, &u);
 230                 free(s);
 231
 232                 if (r >= 0 && u != (uint32_t) -1 && u > 0) {
 233                         *mode = SESSION_ID_AUDIT;
 234                         return (uint64_t) u;
 235                 }
 236         }
 237
 238         /* Second attempt, use our own counter. */
 239         if ((fd = open_file_and_lock(RUNTIME_DIR "/user/.pam-systemd-session")) >= 0) {
 240                 uint64_t counter;
 241                 ssize_t r;
 242
 243                 /* We do a bit of endianess swapping here, just to be
 244                  * sure. /var should be machine specific anyway, and
 245                  * /var/run even mounted from tmpfs, so this
 246                  * byteswapping should really not be necessary. But
 247                  * then again, you never know, so let's avoid any
 248                  * risk. */
 249
 250                 if (loop_read(fd, &counter, sizeof(counter), false) != sizeof(counter))
 251                         counter = 1;
 252                 else
 253                         counter = le64toh(counter) + 1;
 254
 255                 if (lseek(fd, 0, SEEK_SET) == 0) {
 256                         uint64_t swapped = htole64(counter);
 257
 258                         r = loop_write(fd, &swapped, sizeof(swapped), false);
 259
 260                         if (r != sizeof(swapped))
 261                                 r = -EIO;
 262                 } else
 263                         r = -errno;
 264
 265                 close_nointr_nofail(fd);
 266
 267                 if (r >= 0) {
 268                         *mode = SESSION_ID_COUNTER;
 269                         return counter;
 270                 }
 271         }
 272
 273         *mode = SESSION_ID_RANDOM;
 274
 275         /* Last attempt, pick a random value */
 276         return (uint64_t) random_ull();
 277 }
 278 static int get_user_data(
 279                 pam_handle_t *handle,
 280                 const char **ret_username,
 281                 struct passwd **ret_pw) {
 282
 283         const char *username = NULL;
 284         struct passwd *pw = NULL;
 285         int r;
 286         bool have_loginuid = false;
 287         char *s;
 288
 289         assert(handle);
 290         assert(ret_username);
 291         assert(ret_pw);
 292
 293         if (read_one_line_file("/proc/self/loginuid", &s) >= 0) {
 294                 uint32_t u;
 295
 296                 r = safe_atou32(s, &u);
 297                 free(s);
 298
 299                 if (r >= 0 && u != (uint32_t) -1 && u > 0) {
 300                         have_loginuid = true;
 301                         pw = pam_modutil_getpwuid(handle, u);
 302                 }
 303         }
 304
 305         if (!have_loginuid) {
 306                 if ((r = pam_get_user(handle, &username, NULL)) != PAM_SUCCESS) {
 307                         pam_syslog(handle, LOG_ERR, "Failed to get user name.");
 308                         return r;
 309                 }
 310
 311                 if (!username || !*username) {
 312                         pam_syslog(handle, LOG_ERR, "User name not valid.");
 313                         return PAM_AUTH_ERR;
 314                 }
 315
 316                 pw = pam_modutil_getpwnam(handle, username);
 317         }
 318
 319         if (!pw) {
 320                 pam_syslog(handle, LOG_ERR, "Failed to get user data.");
 321                 return PAM_USER_UNKNOWN;
 322         }
 323
 324         *ret_pw = pw;
 325         *ret_username = username ? username : pw->pw_name;
 326
 327         return PAM_SUCCESS;
 328 }
 329
 330 static int create_user_group(
 331                 pam_handle_t *handle,
 332                 const char *controller,
 333                 const char *group,
 334                 struct passwd *pw,
 335                 bool attach,
 336                 bool remember) {
 337
 338         int r;
 339
 340         assert(handle);
 341         assert(group);
 342
 343         if (attach)
 344                 r = cg_create_and_attach(controller, group, 0);
 345         else
 346                 r = cg_create(controller, group);
 347
 348         if (r < 0) {
 349                 pam_syslog(handle, LOG_ERR, "Failed to create cgroup: %s", strerror(-r));
 350                 return PAM_SESSION_ERR;
 351         }
 352
 353         if (r > 0 && remember) {
 354                 /* Remember that it was us who created this group, and
 355                  * that hence we need to remove it too. This is a
 356                  * protection against removing the cgroup when run
 357                  * recursively. */
 358                 if ((r = pam_set_data(handle, "systemd.created", INT_TO_PTR(1), NULL)) != PAM_SUCCESS) {
 359                         pam_syslog(handle, LOG_ERR, "Failed to install created variable.");
 360                         return r;
 361                 }
 362         }
 363
 364         if ((r = cg_set_task_access(controller, group, 0644, pw->pw_uid, pw->pw_gid)) < 0 ||
 365             (r = cg_set_group_access(controller, group, 0755, pw->pw_uid, pw->pw_gid)) < 0) {
 366                 pam_syslog(handle, LOG_ERR, "Failed to change access modes: %s", strerror(-r));
 367                 return PAM_SESSION_ERR;
 368         }
 369
 370         return PAM_SUCCESS;
 371 }
 372
 373 static int reset_group(
 374                 pam_handle_t *handle,
 375                 const char *controller) {
 376
 377         int r;
 378
 379         assert(handle);
 380
 381         if ((r = cg_attach(controller, "/", 0)) < 0) {
 382                 pam_syslog(handle, LOG_ERR, "Failed to reset cgroup for controller %s: %s", controller, strerror(-r));
 383                 return PAM_SESSION_ERR;
 384         }
 385
 386         return PAM_SUCCESS;
 387 }
 388
 389 _public_ PAM_EXTERN int pam_sm_open_session(
 390                 pam_handle_t *handle,
 391                 int flags,
 392                 int argc, const char **argv) {
 393
 394         const char *username = NULL;
 395         struct passwd *pw;
 396         int r;
 397         char *buf = NULL;
 398         int lock_fd = -1;
 399         bool create_session = true;
 400         char **controllers = NULL, **reset_controllers = NULL, **c;
 401
 402         assert(handle);
 403
 404         /* pam_syslog(handle, LOG_DEBUG, "pam-systemd initializing"); */
 405
 406         /* Make this a NOP on non-systemd systems */
 407         if (sd_booted() <= 0)
 408                 return PAM_SUCCESS;
 409
 410         if (parse_argv(handle,
 411                        argc, argv,
 412                        &create_session, NULL, NULL,
 413                        &controllers, &reset_controllers,
 414                        NULL, NULL) < 0)
 415                 return PAM_SESSION_ERR;
 416
 417         if ((r = get_user_data(handle, &username, &pw)) != PAM_SUCCESS)
 418                 goto finish;
 419
 420         if (safe_mkdir(RUNTIME_DIR "/user", 0755, 0, 0) < 0) {
 421                 pam_syslog(handle, LOG_ERR, "Failed to create runtime directory: %m");
 422                 r = PAM_SYSTEM_ERR;
 423                 goto finish;
 424         }
 425
 426         if ((lock_fd = open_file_and_lock(RUNTIME_DIR "/user/.pam-systemd-lock")) < 0) {
 427                 pam_syslog(handle, LOG_ERR, "Failed to lock runtime directory: %m");
 428                 r = PAM_SYSTEM_ERR;
 429                 goto finish;
 430         }
 431
 432         /* Create /var/run/$USER */
 433         free(buf);
 434         if (asprintf(&buf, RUNTIME_DIR "/user/%s", username) < 0) {
 435                 r = PAM_BUF_ERR;
 436                 goto finish;
 437         }
 438
 439         if (safe_mkdir(buf, 0700, pw->pw_uid, pw->pw_gid) < 0) {
 440                 pam_syslog(handle, LOG_WARNING, "Failed to create runtime directory: %m");
 441                 r = PAM_SYSTEM_ERR;
 442                 goto finish;
 443         } else if ((r = pam_misc_setenv(handle, "XDG_RUNTIME_DIR", buf, 0)) != PAM_SUCCESS) {
 444                 pam_syslog(handle, LOG_ERR, "Failed to set runtime dir.");
 445                 goto finish;
 446         }
 447
 448         free(buf);
 449         buf = NULL;
 450
 451         if (create_session) {
 452                 const char *id;
 453
 454                 /* Reuse or create XDG session ID */
 455                 if (!(id = pam_getenv(handle, "XDG_SESSION_ID"))) {
 456                         int mode;
 457
 458                         if (asprintf(&buf, "%llux", (unsigned long long) get_session_id(&mode)) < 0) {
 459                                 r = PAM_BUF_ERR;
 460                                 goto finish;
 461                         }
 462
 463                         /* To avoid id clashes we add the session id
 464                          * source to our session ids. Note that the
 465                          * session id source might change during
 466                          * runtime, because a filesystem became
 467                          * writable or the system reconfigured. */
 468                         buf[strlen(buf)-1] =
 469                                 mode != SESSION_ID_AUDIT ? (char) mode : 0;
 470
 471                         if ((r = pam_misc_setenv(handle, "XDG_SESSION_ID", buf, 0)) != PAM_SUCCESS) {
 472                                 pam_syslog(handle, LOG_ERR, "Failed to set session id.");
 473                                 goto finish;
 474                         }
 475
 476                         if (!(id = pam_getenv(handle, "XDG_SESSION_ID"))) {
 477                                 pam_syslog(handle, LOG_ERR, "Failed to get session id.");
 478                                 r = PAM_SESSION_ERR;
 479                                 goto finish;
 480                         }
 481                 }
 482
 483                 r = asprintf(&buf, "/user/%s/%s", username, id);
 484         } else
 485                 r = asprintf(&buf, "/user/%s/master", username);
 486
 487         if (r < 0) {
 488                 r = PAM_BUF_ERR;
 489                 goto finish;
 490         }
 491
 492         pam_syslog(handle, LOG_INFO, "Moving new user session for %s into control group %s.", username, buf);
 493
 494         if ((r = create_user_group(handle, SYSTEMD_CGROUP_CONTROLLER, buf, pw, true, true)) != PAM_SUCCESS)
 495                 goto finish;
 496
 497         /* The additional controllers don't really matter, so we
 498          * ignore the return value */
 499         STRV_FOREACH(c, controllers)
 500                 create_user_group(handle, *c, buf, pw, true, false);
 501
 502         STRV_FOREACH(c, reset_controllers)
 503                 reset_group(handle, *c);
 504
 505         r = PAM_SUCCESS;
 506
 507 finish:
 508         free(buf);
 509
 510         if (lock_fd >= 0)
 511                 close_nointr_nofail(lock_fd);
 512
 513         strv_free(controllers);
 514         strv_free(reset_controllers);
 515
 516         return r;
 517 }
 518
 519 static int session_remains(pam_handle_t *handle, const char *user_path) {
 520         int r;
 521         bool remains = false;
 522         DIR *d;
 523         char *subgroup;
 524
 525         if ((r = cg_enumerate_subgroups(SYSTEMD_CGROUP_CONTROLLER, user_path, &d)) < 0)
 526                 return r;
 527
 528         while ((r = cg_read_subgroup(d, &subgroup)) > 0) {
 529
 530                 remains = !streq(subgroup, "master");
 531                 free(subgroup);
 532
 533                 if (remains)
 534                         break;
 535         }
 536
 537         closedir(d);
 538
 539         if (r < 0)
 540                 return r;
 541
 542         return !!remains;
 543 }
 544
 545 static bool check_user_lists(
 546                 pam_handle_t *handle,
 547                 uid_t uid,
 548                 char **kill_only_users,
 549                 char **kill_exclude_users) {
 550
 551         const char *name = NULL;
 552         char **l;
 553
 554         assert(handle);
 555
 556         if (uid == 0)
 557                 name = "root"; /* Avoid obvious NSS requests, to suppress network traffic */
 558         else {
 559                 struct passwd *pw;
 560
 561                 if ((pw = pam_modutil_getpwuid(handle, uid)))
 562                         name = pw->pw_name;
 563         }
 564
 565         STRV_FOREACH(l, kill_exclude_users) {
 566                 uint32_t id;
 567
 568                 if (safe_atou32(*l, &id) >= 0)
 569                         if ((uid_t) id == uid)
 570                                 return false;
 571
 572                 if (name && streq(name, *l))
 573                         return false;
 574         }
 575
 576         if (strv_isempty(kill_only_users))
 577                 return true;
 578
 579         STRV_FOREACH(l, kill_only_users) {
 580                 uint32_t id;
 581
 582                 if (safe_atou32(*l, &id) >= 0)
 583                         if ((uid_t) id == uid)
 584                                 return true;
 585
 586                 if (name && streq(name, *l))
 587                         return true;
 588         }
 589
 590         return false;
 591 }
 592
 593 _public_ PAM_EXTERN int pam_sm_close_session(
 594                 pam_handle_t *handle,
 595                 int flags,
 596                 int argc, const char **argv) {
 597
 598         const char *username = NULL;
 599         bool kill_session = false;
 600         bool kill_user = false;
 601         int lock_fd = -1, r;
 602         char *session_path = NULL, *nosession_path = NULL, *user_path = NULL;
 603         const char *id;
 604         struct passwd *pw;
 605         const void *created = NULL;
 606         char **controllers = NULL, **c, **kill_only_users = NULL, **kill_exclude_users = NULL;
 607
 608         assert(handle);
 609
 610         /* Make this a NOP on non-systemd systems */
 611         if (sd_booted() <= 0)
 612                 return PAM_SUCCESS;
 613
 614         if (parse_argv(handle,
 615                        argc, argv,
 616                        NULL, &kill_session, &kill_user,
 617                        &controllers, NULL,
 618                        &kill_only_users, &kill_exclude_users) < 0)
 619                 return PAM_SESSION_ERR;
 620
 621         if ((r = get_user_data(handle, &username, &pw)) != PAM_SUCCESS)
 622                 goto finish;
 623
 624         if ((lock_fd = open_file_and_lock(RUNTIME_DIR "/user/.pam-systemd-lock")) < 0) {
 625                 pam_syslog(handle, LOG_ERR, "Failed to lock runtime directory: %m");
 626                 r = PAM_SYSTEM_ERR;
 627                 goto finish;
 628         }
 629
 630         /* We are probably still in some session/user dir. Move ourselves out of the way as first step */
 631         if ((r = cg_attach(SYSTEMD_CGROUP_CONTROLLER, "/user", 0)) < 0)
 632                 pam_syslog(handle, LOG_ERR, "Failed to move us away: %s", strerror(-r));
 633
 634         STRV_FOREACH(c, controllers)
 635                 if ((r = cg_attach(*c, "/user", 0)) < 0)
 636                         pam_syslog(handle, LOG_ERR, "Failed to move us away in %s hierarchy: %s", *c, strerror(-r));
 637
 638         if (asprintf(&user_path, "/user/%s", username) < 0) {
 639                 r = PAM_BUF_ERR;
 640                 goto finish;
 641         }
 642
 643         pam_get_data(handle, "systemd.created", &created);
 644
 645         if ((id = pam_getenv(handle, "XDG_SESSION_ID")) && created) {
 646
 647                 if (asprintf(&session_path, "/user/%s/%s", username, id) < 0 ||
 648                     asprintf(&nosession_path, "/user/%s/master", username) < 0) {
 649                         r = PAM_BUF_ERR;
 650                         goto finish;
 651                 }
 652
 653                 if (kill_session && check_user_lists(handle, pw->pw_uid, kill_only_users, kill_exclude_users))  {
 654                         pam_syslog(handle, LOG_INFO, "Killing remaining processes of user session %s of %s.", id, username);
 655
 656                         /* Kill processes in session cgroup, and delete it */
 657                         if ((r = cg_kill_recursive_and_wait(SYSTEMD_CGROUP_CONTROLLER, session_path, true)) < 0)
 658                                 pam_syslog(handle, LOG_ERR, "Failed to kill session cgroup: %s", strerror(-r));
 659                 } else {
 660                         pam_syslog(handle, LOG_INFO, "Moving remaining processes of user session %s of %s into control group %s.", id, username, nosession_path);
 661
 662                         /* Migrate processes from session to user
 663                          * cgroup. First, try to create the user group
 664                          * in case it doesn't exist yet. Also, delete
 665                          * the session group. */
 666                         create_user_group(handle, SYSTEMD_CGROUP_CONTROLLER, nosession_path, pw, false, false);
 667
 668                         if ((r = cg_migrate_recursive(SYSTEMD_CGROUP_CONTROLLER, session_path, nosession_path, false, true)) < 0)
 669                                 pam_syslog(handle, LOG_ERR, "Failed to migrate session cgroup: %s", strerror(-r));
 670                 }
 671
 672                 STRV_FOREACH(c, controllers) {
 673                         create_user_group(handle, *c, nosession_path, pw, false, false);
 674
 675                         if ((r = cg_migrate_recursive(*c, session_path, nosession_path, false, true)) < 0)
 676                                 pam_syslog(handle, LOG_ERR, "Failed to migrate session cgroup in hierarchy %s: %s", *c, strerror(-r));
 677                 }
 678         }
 679
 680         /* GC user tree */
 681         cg_trim(SYSTEMD_CGROUP_CONTROLLER, user_path, false);
 682
 683         if ((r = session_remains(handle, user_path)) < 0)
 684                 pam_syslog(handle, LOG_ERR, "Failed to determine whether a session remains: %s", strerror(-r));
 685
 686         /* Kill user processes not attached to any session */
 687         if (kill_user && r == 0 && check_user_lists(handle, pw->pw_uid, kill_only_users, kill_exclude_users)) {
 688
 689                 /* Kill user cgroup */
 690                 if ((r = cg_kill_recursive_and_wait(SYSTEMD_CGROUP_CONTROLLER, user_path, true)) < 0)
 691                         pam_syslog(handle, LOG_ERR, "Failed to kill user cgroup: %s", strerror(-r));
 692         } else {
 693
 694                 if ((r = cg_is_empty_recursive(SYSTEMD_CGROUP_CONTROLLER, user_path, true)) < 0)
 695                         pam_syslog(handle, LOG_ERR, "Failed to check user cgroup: %s", strerror(-r));
 696
 697                 /* Remove user cgroup */
 698                 if (r > 0) {
 699                         if ((r = cg_delete(SYSTEMD_CGROUP_CONTROLLER, user_path)) < 0)
 700                                 pam_syslog(handle, LOG_ERR, "Failed to delete user cgroup: %s", strerror(-r));
 701
 702                 /* If we managed to find somebody, don't cleanup the cgroup. */
 703                 } else if (r == 0)
 704                         r = -EBUSY;
 705         }
 706
 707         STRV_FOREACH(c, controllers)
 708                 cg_trim(*c, user_path, true);
 709
 710         if (r >= 0) {
 711                 const char *runtime_dir;
 712
 713                 if ((runtime_dir = pam_getenv(handle, "XDG_RUNTIME_DIR")))
 714                         if ((r = rm_rf(runtime_dir, false, true)) < 0)
 715                                 pam_syslog(handle, LOG_ERR, "Failed to remove runtime directory: %s", strerror(-r));
 716         }
 717
 718         /* pam_syslog(handle, LOG_DEBUG, "pam-systemd done"); */
 719
 720         r = PAM_SUCCESS;
 721
 722 finish:
 723         if (lock_fd >= 0)
 724                 close_nointr_nofail(lock_fd);
 725
 726         free(session_path);
 727         free(nosession_path);
 728         free(user_path);
 729
 730         strv_free(controllers);
 731         strv_free(kill_exclude_users);
 732         strv_free(kill_only_users);
 733
 734         return r;
 735 }