]>
Commit | Line | Data |
---|---|---|
0ad19a3f | 1 | /* |
2 | * lxc: linux Container library | |
3 | * | |
4 | * (C) Copyright IBM Corp. 2007, 2008 | |
5 | * | |
6 | * Authors: | |
9afe19d6 | 7 | * Daniel Lezcano <daniel.lezcano at free.fr> |
0ad19a3f | 8 | * |
9 | * This library is free software; you can redistribute it and/or | |
10 | * modify it under the terms of the GNU Lesser General Public | |
11 | * License as published by the Free Software Foundation; either | |
12 | * version 2.1 of the License, or (at your option) any later version. | |
13 | * | |
14 | * This library is distributed in the hope that it will be useful, | |
15 | * but WITHOUT ANY WARRANTY; without even the implied warranty of | |
16 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU | |
17 | * Lesser General Public License for more details. | |
18 | * | |
19 | * You should have received a copy of the GNU Lesser General Public | |
20 | * License along with this library; if not, write to the Free Software | |
250b1eec | 21 | * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA |
0ad19a3f | 22 | */ |
23 | ||
f549edcc GK |
24 | #include "config.h" |
25 | ||
0ad19a3f | 26 | #include <stdio.h> |
27 | #undef _GNU_SOURCE | |
28 | #include <string.h> | |
29 | #include <stdlib.h> | |
30 | #include <dirent.h> | |
31 | #include <errno.h> | |
32 | #include <unistd.h> | |
33 | #include <signal.h> | |
b0a33c1e | 34 | #include <fcntl.h> |
35 | #include <termios.h> | |
0ad19a3f | 36 | #include <sys/param.h> |
37 | #include <sys/file.h> | |
f4d507d5 | 38 | #include <sys/mount.h> |
b4f8660e | 39 | #include <sys/stat.h> |
0ad19a3f | 40 | #include <sys/types.h> |
8173e600 | 41 | #include <sys/socket.h> |
0ad19a3f | 42 | #include <sys/prctl.h> |
ddceb1f9 | 43 | #include <sys/types.h> |
0ad19a3f | 44 | #include <sys/wait.h> |
b0a33c1e | 45 | #include <sys/un.h> |
46 | #include <sys/poll.h> | |
8173e600 | 47 | #include <sys/syscall.h> |
ff218c25 | 48 | |
495d2046 SG |
49 | #if HAVE_SYS_CAPABILITY_H |
50 | #include <sys/capability.h> | |
51 | #endif | |
52 | ||
656994bb MH |
53 | #if !HAVE_DECL_PR_CAPBSET_DROP |
54 | #define PR_CAPBSET_DROP 24 | |
55 | #endif | |
56 | ||
63376d7d DL |
57 | #include "start.h" |
58 | #include "conf.h" | |
59 | #include "log.h" | |
563f2f2c | 60 | #include "cgroup.h" |
e2bcd7db | 61 | #include "error.h" |
b0a33c1e | 62 | #include "af_unix.h" |
63 | #include "mainloop.h" | |
63376d7d | 64 | #include "utils.h" |
565c2d76 | 65 | #include "lxcutmp.h" |
63376d7d | 66 | #include "monitor.h" |
96fa1ff0 | 67 | #include "commands.h" |
63376d7d | 68 | #include "console.h" |
3c22086f | 69 | #include "sync.h" |
f549edcc | 70 | #include "namespace.h" |
e075f5d9 | 71 | #include "apparmor.h" |
0d0527a9 | 72 | #include "lxcseccomp.h" |
8173e600 | 73 | #include "caps.h" |
36eb9bde CLG |
74 | |
75 | lxc_log_define(lxc_start, lxc); | |
76 | ||
80090207 CLG |
77 | static int match_fd(int fd) |
78 | { | |
79 | return (fd == 0 || fd == 1 || fd == 2); | |
80 | } | |
81 | ||
b119f362 | 82 | int lxc_check_inherited(struct lxc_conf *conf, int fd_to_ignore) |
80090207 CLG |
83 | { |
84 | struct dirent dirent, *direntp; | |
85 | int fd, fddir; | |
86 | DIR *dir; | |
80090207 | 87 | |
b119f362 | 88 | restart: |
80090207 CLG |
89 | dir = opendir("/proc/self/fd"); |
90 | if (!dir) { | |
91 | WARN("failed to open directory: %m"); | |
92 | return -1; | |
93 | } | |
94 | ||
95 | fddir = dirfd(dir); | |
96 | ||
97 | while (!readdir_r(dir, &dirent, &direntp)) { | |
80090207 CLG |
98 | if (!direntp) |
99 | break; | |
100 | ||
101 | if (!strcmp(direntp->d_name, ".")) | |
102 | continue; | |
103 | ||
104 | if (!strcmp(direntp->d_name, "..")) | |
105 | continue; | |
106 | ||
107 | fd = atoi(direntp->d_name); | |
108 | ||
f2faa8fa | 109 | if (fd == fddir || fd == lxc_log_fd || fd == fd_to_ignore) |
80090207 CLG |
110 | continue; |
111 | ||
112 | if (match_fd(fd)) | |
113 | continue; | |
80090207 | 114 | |
b119f362 SH |
115 | if (conf->close_all_fds) { |
116 | close(fd); | |
117 | closedir(dir); | |
118 | INFO("closed inherited fd %d", fd); | |
119 | goto restart; | |
120 | } | |
92c7f629 | 121 | WARN("inherited fd %d", fd); |
80090207 CLG |
122 | } |
123 | ||
92c7f629 GK |
124 | closedir(dir); /* cannot fail */ |
125 | return 0; | |
80090207 CLG |
126 | } |
127 | ||
83ee7875 | 128 | static int setup_signal_fd(sigset_t *oldmask) |
b0a33c1e | 129 | { |
130 | sigset_t mask; | |
131 | int fd; | |
132 | ||
f3304a29 FW |
133 | /* Block everything except serious error signals */ |
134 | if (sigfillset(&mask) || | |
135 | sigdelset(&mask, SIGILL) || | |
136 | sigdelset(&mask, SIGSEGV) || | |
137 | sigdelset(&mask, SIGBUS) || | |
b5159817 | 138 | sigdelset(&mask, SIGWINCH) || |
f3304a29 FW |
139 | sigprocmask(SIG_BLOCK, &mask, oldmask)) { |
140 | SYSERROR("failed to set signal mask"); | |
b0a33c1e | 141 | return -1; |
142 | } | |
143 | ||
144 | fd = signalfd(-1, &mask, 0); | |
145 | if (fd < 0) { | |
36eb9bde | 146 | SYSERROR("failed to create the signal fd"); |
b0a33c1e | 147 | return -1; |
148 | } | |
149 | ||
150 | if (fcntl(fd, F_SETFD, FD_CLOEXEC)) { | |
36eb9bde | 151 | SYSERROR("failed to set sigfd to close-on-exec"); |
b0a33c1e | 152 | close(fd); |
153 | return -1; | |
154 | } | |
155 | ||
1ac470c0 DL |
156 | DEBUG("sigchild handler set"); |
157 | ||
b0a33c1e | 158 | return fd; |
159 | } | |
160 | ||
83ee7875 | 161 | static int signal_handler(int fd, void *data, |
b0a33c1e | 162 | struct lxc_epoll_descr *descr) |
163 | { | |
15cd25fd | 164 | struct signalfd_siginfo siginfo; |
80507ee8 | 165 | siginfo_t info; |
15cd25fd | 166 | int ret; |
82d89dce | 167 | pid_t *pid = data; |
80507ee8 | 168 | bool init_died = false; |
15cd25fd DL |
169 | |
170 | ret = read(fd, &siginfo, sizeof(siginfo)); | |
171 | if (ret < 0) { | |
f3304a29 | 172 | ERROR("failed to read signal info"); |
15cd25fd DL |
173 | return -1; |
174 | } | |
175 | ||
176 | if (ret != sizeof(siginfo)) { | |
177 | ERROR("unexpected siginfo size"); | |
178 | return -1; | |
179 | } | |
180 | ||
80507ee8 SH |
181 | // check whether init is running |
182 | info.si_pid = 0; | |
183 | ret = waitid(P_PID, *pid, &info, WEXITED | WNOWAIT | WNOHANG); | |
184 | if (ret == 0 && info.si_pid == *pid) { | |
185 | init_died = true; | |
186 | } | |
187 | ||
f3304a29 FW |
188 | if (siginfo.ssi_signo != SIGCHLD) { |
189 | kill(*pid, siginfo.ssi_signo); | |
190 | INFO("forwarded signal %d to pid %d", siginfo.ssi_signo, *pid); | |
80507ee8 | 191 | return init_died ? 1 : 0; |
f3304a29 FW |
192 | } |
193 | ||
15cd25fd DL |
194 | if (siginfo.ssi_code == CLD_STOPPED || |
195 | siginfo.ssi_code == CLD_CONTINUED) { | |
196 | INFO("container init process was stopped/continued"); | |
80507ee8 | 197 | return init_died ? 1 : 0; |
15cd25fd | 198 | } |
1ac470c0 | 199 | |
82d89dce DL |
200 | /* more robustness, protect ourself from a SIGCHLD sent |
201 | * by a process different from the container init | |
202 | */ | |
203 | if (siginfo.ssi_pid != *pid) { | |
204 | WARN("invalid pid for SIGCHLD"); | |
80507ee8 | 205 | return init_died ? 1 : 0; |
82d89dce DL |
206 | } |
207 | ||
15cd25fd | 208 | DEBUG("container init process exited"); |
b0a33c1e | 209 | return 1; |
210 | } | |
211 | ||
25c2aca5 | 212 | int lxc_set_state(const char *name, struct lxc_handler *handler, lxc_state_t state) |
66aeffc7 DL |
213 | { |
214 | handler->state = state; | |
9123e471 | 215 | lxc_monitor_send_state(name, state, handler->lxcpath); |
66aeffc7 DL |
216 | return 0; |
217 | } | |
218 | ||
1bc5cc8c | 219 | int lxc_poll(const char *name, struct lxc_handler *handler) |
b0a33c1e | 220 | { |
ca5f7926 DL |
221 | int sigfd = handler->sigfd; |
222 | int pid = handler->pid; | |
b0a33c1e | 223 | struct lxc_epoll_descr descr; |
224 | ||
a9e61274 | 225 | if (lxc_mainloop_open(&descr)) { |
36eb9bde | 226 | ERROR("failed to create mainloop"); |
50c8bf05 | 227 | goto out_sigfd; |
b0a33c1e | 228 | } |
229 | ||
83ee7875 | 230 | if (lxc_mainloop_add_handler(&descr, sigfd, signal_handler, &pid)) { |
36eb9bde | 231 | ERROR("failed to add handler for the signal"); |
b0a33c1e | 232 | goto out_mainloop_open; |
233 | } | |
234 | ||
63376d7d DL |
235 | if (lxc_console_mainloop_add(&descr, handler)) { |
236 | ERROR("failed to add console handler to mainloop"); | |
237 | goto out_mainloop_open; | |
238 | } | |
239 | ||
ef6e34ee | 240 | if (lxc_cmd_mainloop_add(name, &descr, handler)) { |
563f2f2c | 241 | ERROR("failed to add command handler to mainloop"); |
96fa1ff0 | 242 | goto out_mainloop_open; |
563f2f2c DL |
243 | } |
244 | ||
828695d9 | 245 | if (handler->conf->need_utmp_watch) { |
495d2046 | 246 | #if HAVE_SYS_CAPABILITY_H |
828695d9 SH |
247 | if (lxc_utmp_mainloop_add(&descr, handler)) { |
248 | ERROR("failed to add utmp handler to mainloop"); | |
249 | goto out_mainloop_open; | |
250 | } | |
495d2046 SG |
251 | #else |
252 | DEBUG("not starting utmp handler as cap_sys_boot cannot be dropped without capabilities support\n"); | |
253 | #endif | |
563f2f2c | 254 | } |
b0a33c1e | 255 | |
e51d4895 | 256 | return lxc_mainloop(&descr, -1); |
b0a33c1e | 257 | |
258 | out_mainloop_open: | |
259 | lxc_mainloop_close(&descr); | |
b0a33c1e | 260 | out_sigfd: |
261 | close(sigfd); | |
c3e13372 | 262 | return -1; |
b0a33c1e | 263 | } |
264 | ||
13f5be62 | 265 | struct lxc_handler *lxc_init(const char *name, struct lxc_conf *conf, const char *lxcpath) |
59eb99ba | 266 | { |
3a0f472d DL |
267 | struct lxc_handler *handler; |
268 | ||
269 | handler = malloc(sizeof(*handler)); | |
270 | if (!handler) | |
271 | return NULL; | |
59eb99ba DL |
272 | |
273 | memset(handler, 0, sizeof(*handler)); | |
274 | ||
fae349da | 275 | handler->conf = conf; |
9123e471 | 276 | handler->lxcpath = lxcpath; |
5c068da9 | 277 | handler->pinfd = -1; |
fae349da | 278 | |
e075f5d9 | 279 | apparmor_handler_init(handler); |
3bdf52d7 DL |
280 | handler->name = strdup(name); |
281 | if (!handler->name) { | |
282 | ERROR("failed to allocate memory"); | |
283 | goto out_free; | |
284 | } | |
285 | ||
ef6e34ee | 286 | if (lxc_cmd_init(name, handler, lxcpath)) |
d2e30e99 DE |
287 | goto out_free_name; |
288 | ||
8f2c3a70 SH |
289 | if (lxc_read_seccomp_config(conf) != 0) { |
290 | ERROR("failed loading seccomp policy"); | |
d2e30e99 | 291 | goto out_close_maincmd_fd; |
8f2c3a70 SH |
292 | } |
293 | ||
051151de | 294 | /* Begin by setting the state to STARTING */ |
25c2aca5 | 295 | if (lxc_set_state(name, handler, STARTING)) { |
59eb99ba | 296 | ERROR("failed to set state '%s'", lxc_state2str(STARTING)); |
051151de | 297 | goto out_close_maincmd_fd; |
0ad19a3f | 298 | } |
299 | ||
f7bee6c6 MW |
300 | /* Start of environment variable setup for hooks */ |
301 | if (setenv("LXC_NAME", name, 1)) { | |
302 | SYSERROR("failed to set environment variable for container name"); | |
303 | } | |
304 | if (setenv("LXC_CONFIG_FILE", conf->rcfile, 1)) { | |
305 | SYSERROR("failed to set environment variable for config path"); | |
306 | } | |
307 | if (setenv("LXC_ROOTFS_MOUNT", conf->rootfs.mount, 1)) { | |
308 | SYSERROR("failed to set environment variable for rootfs mount"); | |
309 | } | |
310 | if (setenv("LXC_ROOTFS_PATH", conf->rootfs.path, 1)) { | |
311 | SYSERROR("failed to set environment variable for rootfs mount"); | |
312 | } | |
313 | if (conf->console.path && setenv("LXC_CONSOLE", conf->console.path, 1)) { | |
314 | SYSERROR("failed to set environment variable for console path"); | |
315 | } | |
316 | if (conf->console.log_path && setenv("LXC_CONSOLE_LOGPATH", conf->console.log_path, 1)) { | |
317 | SYSERROR("failed to set environment variable for console log"); | |
318 | } | |
319 | /* End of environment variable setup for hooks */ | |
320 | ||
283678ed | 321 | if (run_lxc_hooks(name, "pre-start", conf, handler->lxcpath, NULL)) { |
773fb9ca SH |
322 | ERROR("failed to run pre-start hooks for container '%s'.", name); |
323 | goto out_aborting; | |
324 | } | |
26ddeedd | 325 | |
fae349da | 326 | if (lxc_create_tty(name, conf)) { |
36eb9bde | 327 | ERROR("failed to create the ttys"); |
59eb99ba | 328 | goto out_aborting; |
b0a33c1e | 329 | } |
330 | ||
331 | /* the signal fd has to be created before forking otherwise | |
332 | * if the child process exits before we setup the signal fd, | |
333 | * the event will be lost and the command will be stuck */ | |
83ee7875 | 334 | handler->sigfd = setup_signal_fd(&handler->oldmask); |
59eb99ba | 335 | if (handler->sigfd < 0) { |
36eb9bde | 336 | ERROR("failed to set sigchild fd handler"); |
b5159817 DE |
337 | goto out_delete_tty; |
338 | } | |
339 | ||
340 | /* do this after setting up signals since it might unblock SIGWINCH */ | |
341 | if (lxc_console_create(conf)) { | |
342 | ERROR("failed to create console"); | |
343 | goto out_restore_sigmask; | |
b0a33c1e | 344 | } |
345 | ||
c3e13372 | 346 | INFO("'%s' is initialized", name); |
3a0f472d | 347 | return handler; |
59eb99ba | 348 | |
b5159817 DE |
349 | out_restore_sigmask: |
350 | sigprocmask(SIG_SETMASK, &handler->oldmask, NULL); | |
59eb99ba | 351 | out_delete_tty: |
fae349da | 352 | lxc_delete_tty(&conf->tty_info); |
59eb99ba | 353 | out_aborting: |
25c2aca5 | 354 | lxc_set_state(name, handler, ABORTING); |
d2e30e99 DE |
355 | out_close_maincmd_fd: |
356 | close(conf->maincmd_fd); | |
357 | conf->maincmd_fd = -1; | |
3bdf52d7 DL |
358 | out_free_name: |
359 | free(handler->name); | |
360 | handler->name = NULL; | |
3a0f472d DL |
361 | out_free: |
362 | free(handler); | |
c3e13372 | 363 | return NULL; |
59eb99ba DL |
364 | } |
365 | ||
ae5c8b8e | 366 | static void lxc_fini(const char *name, struct lxc_handler *handler) |
59eb99ba DL |
367 | { |
368 | /* The STOPPING state is there for future cleanup code | |
369 | * which can take awhile | |
370 | */ | |
25c2aca5 MN |
371 | lxc_set_state(name, handler, STOPPING); |
372 | lxc_set_state(name, handler, STOPPED); | |
59eb99ba | 373 | |
283678ed | 374 | if (run_lxc_hooks(name, "post-stop", handler->conf, handler->lxcpath, NULL)) |
773fb9ca | 375 | ERROR("failed to run post-stop hooks for container '%s'.", name); |
26ddeedd | 376 | |
83ee7875 | 377 | /* reset mask set by setup_signal_fd */ |
8f64a3f6 MN |
378 | if (sigprocmask(SIG_SETMASK, &handler->oldmask, NULL)) |
379 | WARN("failed to restore sigprocmask"); | |
380 | ||
b5159817 | 381 | lxc_console_delete(&handler->conf->console); |
b2431939 | 382 | lxc_delete_tty(&handler->conf->tty_info); |
d2e30e99 DE |
383 | close(handler->conf->maincmd_fd); |
384 | handler->conf->maincmd_fd = -1; | |
3bdf52d7 | 385 | free(handler->name); |
ae5c8b8e | 386 | if (handler->cgroup) { |
33ad9f1a | 387 | lxc_cgroup_process_info_free_and_remove(handler->cgroup); |
ae5c8b8e SH |
388 | handler->cgroup = NULL; |
389 | } | |
b2431939 | 390 | free(handler); |
59eb99ba DL |
391 | } |
392 | ||
1bc5cc8c | 393 | void lxc_abort(const char *name, struct lxc_handler *handler) |
59eb99ba | 394 | { |
73e608b2 SH |
395 | int ret, status; |
396 | ||
25c2aca5 | 397 | lxc_set_state(name, handler, ABORTING); |
7d9fb3e9 DL |
398 | if (handler->pid > 0) |
399 | kill(handler->pid, SIGKILL); | |
73e608b2 | 400 | while ((ret = waitpid(-1, &status, 0)) > 0) ; |
59eb99ba DL |
401 | } |
402 | ||
828695d9 SH |
403 | #include <sys/reboot.h> |
404 | #include <linux/reboot.h> | |
405 | ||
e2fa1520 SH |
406 | /* |
407 | * reboot(LINUX_REBOOT_CMD_CAD_ON) will return -EINVAL | |
408 | * in a child pid namespace if container reboot support exists. | |
409 | * Otherwise, it will either succeed or return -EPERM. | |
410 | */ | |
411 | static int container_reboot_supported(void *arg) | |
828695d9 | 412 | { |
e2fa1520 | 413 | int *cmd = arg; |
828695d9 | 414 | int ret; |
828695d9 | 415 | |
e2fa1520 SH |
416 | ret = reboot(*cmd); |
417 | if (ret == -1 && errno == EINVAL) | |
418 | return 1; | |
419 | return 0; | |
420 | } | |
421 | ||
b60ed720 | 422 | static int must_drop_cap_sys_boot(struct lxc_conf *conf) |
e2fa1520 SH |
423 | { |
424 | FILE *f = fopen("/proc/sys/kernel/ctrl-alt-del", "r"); | |
b60ed720 | 425 | int ret, cmd, v, flags; |
e2fa1520 | 426 | long stack_size = 4096; |
7f145a6d | 427 | void *stack = alloca(stack_size); |
e2fa1520 SH |
428 | int status; |
429 | pid_t pid; | |
430 | ||
431 | if (!f) { | |
432 | DEBUG("failed to open /proc/sys/kernel/ctrl-alt-del"); | |
828695d9 | 433 | return 1; |
e2fa1520 | 434 | } |
828695d9 SH |
435 | |
436 | ret = fscanf(f, "%d", &v); | |
437 | fclose(f); | |
e2fa1520 SH |
438 | if (ret != 1) { |
439 | DEBUG("Failed to read /proc/sys/kernel/ctrl-alt-del"); | |
828695d9 | 440 | return 1; |
e2fa1520 SH |
441 | } |
442 | cmd = v ? LINUX_REBOOT_CMD_CAD_ON : LINUX_REBOOT_CMD_CAD_OFF; | |
443 | ||
b60ed720 SH |
444 | flags = CLONE_NEWPID | SIGCHLD; |
445 | if (!lxc_list_empty(&conf->id_map)) | |
446 | flags |= CLONE_NEWUSER; | |
447 | ||
7f145a6d | 448 | #ifdef __ia64__ |
b60ed720 | 449 | pid = __clone2(container_reboot_supported, stack, stack_size, flags, &cmd); |
7f145a6d DS |
450 | #else |
451 | stack += stack_size; | |
b60ed720 | 452 | pid = clone(container_reboot_supported, stack, flags, &cmd); |
7f145a6d | 453 | #endif |
e2fa1520 SH |
454 | if (pid < 0) { |
455 | SYSERROR("failed to clone\n"); | |
456 | return -1; | |
457 | } | |
458 | if (wait(&status) < 0) { | |
459 | SYSERROR("unexpected wait error: %m\n"); | |
460 | return -1; | |
461 | } | |
462 | ||
463 | if (WEXITSTATUS(status) != 1) | |
828695d9 | 464 | return 1; |
e2fa1520 | 465 | |
828695d9 SH |
466 | return 0; |
467 | } | |
468 | ||
ffe1e01a | 469 | static int do_start(void *data) |
50e98013 | 470 | { |
23c53af9 | 471 | struct lxc_handler *handler = data; |
50e98013 DL |
472 | |
473 | if (sigprocmask(SIG_SETMASK, &handler->oldmask, NULL)) { | |
474 | SYSERROR("failed to set sigprocmask"); | |
9d7f9e52 | 475 | return -1; |
50e98013 DL |
476 | } |
477 | ||
743ecd2e DL |
478 | /* This prctl must be before the synchro, so if the parent |
479 | * dies before we set the parent death signal, we will detect | |
480 | * its death with the synchro right after, otherwise we have | |
481 | * a window where the parent can exit before we set the pdeath | |
482 | * signal leading to a unsupervized container. | |
483 | */ | |
484 | if (prctl(PR_SET_PDEATHSIG, SIGKILL, 0, 0, 0)) { | |
485 | SYSERROR("failed to set pdeath signal"); | |
486 | return -1; | |
487 | } | |
488 | ||
3c22086f | 489 | lxc_sync_fini_parent(handler); |
50e98013 | 490 | |
2b0e17e4 | 491 | /* don't leak the pinfd to the container */ |
0d03360a SH |
492 | if (handler->pinfd >= 0) |
493 | close(handler->pinfd); | |
2b0e17e4 | 494 | |
3c22086f CLG |
495 | /* Tell the parent task it can begin to configure the |
496 | * container and wait for it to finish | |
497 | */ | |
498 | if (lxc_sync_barrier_parent(handler, LXC_SYNC_CONFIGURE)) | |
9d7f9e52 | 499 | return -1; |
50e98013 | 500 | |
f6d3e3e4 SH |
501 | /* |
502 | * if we are in a new user namespace, become root there to have | |
503 | * privilege over our namespace | |
504 | */ | |
505 | if (!lxc_list_empty(&handler->conf->id_map)) { | |
506 | NOTICE("switching to gid/uid 0 in new user namespace"); | |
507 | if (setgid(0)) { | |
508 | SYSERROR("setgid"); | |
509 | goto out_warn_father; | |
510 | } | |
511 | if (setuid(0)) { | |
512 | SYSERROR("setuid"); | |
513 | goto out_warn_father; | |
514 | } | |
515 | } | |
516 | ||
495d2046 | 517 | #if HAVE_SYS_CAPABILITY_H |
69182a31 | 518 | if (handler->conf->need_utmp_watch) { |
828695d9 SH |
519 | if (prctl(PR_CAPBSET_DROP, CAP_SYS_BOOT, 0, 0, 0)) { |
520 | SYSERROR("failed to remove CAP_SYS_BOOT capability"); | |
c4ea60df | 521 | goto out_warn_father; |
828695d9 | 522 | } |
e2fa1520 | 523 | DEBUG("Dropped cap_sys_boot\n"); |
e2fa1520 | 524 | } |
495d2046 | 525 | #endif |
e2fa1520 SH |
526 | |
527 | /* Setup the container, ip, names, utsname, ... */ | |
283678ed | 528 | if (lxc_setup(handler->name, handler->conf, handler->lxcpath)) { |
e2fa1520 SH |
529 | ERROR("failed to setup the container"); |
530 | goto out_warn_father; | |
531 | } | |
50e98013 | 532 | |
544a48a0 SH |
533 | /* ask father to setup cgroups and wait for him to finish */ |
534 | if (lxc_sync_barrier_parent(handler, LXC_SYNC_CGROUP)) | |
535 | return -1; | |
536 | ||
e075f5d9 SH |
537 | if (apparmor_load(handler) < 0) |
538 | goto out_warn_father; | |
539 | ||
8f2c3a70 SH |
540 | if (lxc_seccomp_load(handler->conf) != 0) |
541 | goto out_warn_father; | |
542 | ||
283678ed | 543 | if (run_lxc_hooks(handler->name, "start", handler->conf, handler->lxcpath, NULL)) { |
773fb9ca SH |
544 | ERROR("failed to run start hooks for container '%s'.", handler->name); |
545 | goto out_warn_father; | |
546 | } | |
fc25b815 | 547 | |
f7bee6c6 MW |
548 | /* The clearenv() and putenv() calls have been moved here |
549 | * to allow us to use enviroment variables passed to the various | |
550 | * hooks, such as the start hook above. Not all of the | |
551 | * variables like CONFIG_PATH or ROOTFS are valid in this | |
552 | * context but others are. */ | |
553 | if (clearenv()) { | |
554 | SYSERROR("failed to clear environment"); | |
555 | /* don't error out though */ | |
556 | } | |
557 | ||
558 | if (putenv("container=lxc")) { | |
559 | SYSERROR("failed to set environment variable"); | |
c4ea60df | 560 | goto out_warn_father; |
f7bee6c6 MW |
561 | } |
562 | ||
773fb9ca | 563 | close(handler->sigfd); |
26ddeedd | 564 | |
e6126dbe MN |
565 | /* after this call, we are in error because this |
566 | * ops should not return as it execs */ | |
c4ea60df | 567 | handler->ops->start(handler, handler->data); |
50e98013 DL |
568 | |
569 | out_warn_father: | |
544a48a0 SH |
570 | /* we want the parent to know something went wrong, so any |
571 | * value other than what it expects is ok. */ | |
3c22086f | 572 | lxc_sync_wake_parent(handler, LXC_SYNC_POST_CONFIGURE); |
50e98013 DL |
573 | return -1; |
574 | } | |
575 | ||
7b35f3d6 SH |
576 | int save_phys_nics(struct lxc_conf *conf) |
577 | { | |
578 | struct lxc_list *iterator; | |
579 | ||
580 | lxc_list_for_each(iterator, &conf->network) { | |
581 | struct lxc_netdev *netdev = iterator->elem; | |
582 | ||
583 | if (netdev->type != LXC_NET_PHYS) | |
584 | continue; | |
585 | conf->saved_nics = realloc(conf->saved_nics, | |
586 | (conf->num_savednics+1)*sizeof(struct saved_nic)); | |
587 | if (!conf->saved_nics) { | |
588 | SYSERROR("failed to allocate memory"); | |
589 | return -1; | |
590 | } | |
591 | conf->saved_nics[conf->num_savednics].ifindex = netdev->ifindex; | |
592 | conf->saved_nics[conf->num_savednics].orig_name = strdup(netdev->link); | |
593 | if (!conf->saved_nics[conf->num_savednics].orig_name) { | |
594 | SYSERROR("failed to allocate memory"); | |
595 | return -1; | |
596 | } | |
597 | INFO("stored saved_nic #%d idx %d name %s\n", conf->num_savednics, | |
598 | conf->saved_nics[conf->num_savednics].ifindex, | |
599 | conf->saved_nics[conf->num_savednics].orig_name); | |
600 | conf->num_savednics++; | |
601 | } | |
602 | ||
603 | return 0; | |
604 | } | |
605 | ||
23c53af9 | 606 | int lxc_spawn(struct lxc_handler *handler) |
59eb99ba | 607 | { |
b98f7d6e | 608 | int failed_before_rename = 0; |
ffe1e01a | 609 | const char *name = handler->name; |
33ad9f1a CS |
610 | struct cgroup_meta_data *cgroup_meta = NULL; |
611 | const char *cgroup_pattern = NULL; | |
50e98013 | 612 | |
3c22086f | 613 | if (lxc_sync_init(handler)) |
9d7f9e52 | 614 | return -1; |
0ad19a3f | 615 | |
d5088cf2 | 616 | handler->clone_flags = CLONE_NEWUTS|CLONE_NEWPID|CLONE_NEWIPC|CLONE_NEWNS; |
f6d3e3e4 SH |
617 | if (!lxc_list_empty(&handler->conf->id_map)) { |
618 | INFO("Cloning a new user namespace"); | |
619 | handler->clone_flags |= CLONE_NEWUSER; | |
620 | } | |
fae349da | 621 | if (!lxc_list_empty(&handler->conf->network)) { |
82d5ae15 | 622 | |
d5088cf2 | 623 | handler->clone_flags |= CLONE_NEWNET; |
0ad19a3f | 624 | |
19a26f82 MK |
625 | /* Find gateway addresses from the link device, which is |
626 | * no longer accessible inside the container. Do this | |
627 | * before creating network interfaces, since goto | |
628 | * out_delete_net does not work before lxc_clone. */ | |
629 | if (lxc_find_gateway_addresses(handler)) { | |
630 | ERROR("failed to find gateway addresses"); | |
631 | lxc_sync_fini(handler); | |
632 | return -1; | |
633 | } | |
634 | ||
82d5ae15 DL |
635 | /* that should be done before the clone because we will |
636 | * fill the netdev index and use them in the child | |
637 | */ | |
e3b4c4c4 | 638 | if (lxc_create_network(handler)) { |
82d5ae15 | 639 | ERROR("failed to create the network"); |
3c22086f | 640 | lxc_sync_fini(handler); |
32e1c760 | 641 | return -1; |
82d5ae15 DL |
642 | } |
643 | } | |
644 | ||
7b35f3d6 SH |
645 | if (save_phys_nics(handler->conf)) { |
646 | ERROR("failed to save physical nic info"); | |
647 | goto out_abort; | |
648 | } | |
649 | ||
33ad9f1a CS |
650 | cgroup_meta = lxc_cgroup_load_meta(); |
651 | if (!cgroup_meta) { | |
652 | ERROR("failed to detect cgroup metadata"); | |
653 | goto out_delete_net; | |
654 | } | |
655 | ||
656 | /* if we are running as root, use system cgroup pattern, otherwise | |
657 | * just create a cgroup under the current one. But also fall back to | |
658 | * that if for some reason reading the configuration fails and no | |
659 | * default value is available | |
660 | */ | |
661 | if (getuid() == 0) | |
662 | cgroup_pattern = lxc_global_config_value("cgroup.pattern"); | |
663 | if (!cgroup_pattern) | |
664 | cgroup_pattern = "%n"; | |
665 | ||
0c547523 SH |
666 | /* |
667 | * if the rootfs is not a blockdev, prevent the container from | |
668 | * marking it readonly. | |
669 | */ | |
670 | ||
2b0e17e4 | 671 | handler->pinfd = pin_rootfs(handler->conf->rootfs.path); |
00ec333b SH |
672 | if (handler->pinfd == -1) |
673 | INFO("failed to pin the container's rootfs"); | |
0c547523 | 674 | |
0ad19a3f | 675 | /* Create a process in a new set of namespaces */ |
d5088cf2 | 676 | handler->pid = lxc_clone(do_start, handler, handler->clone_flags); |
59eb99ba | 677 | if (handler->pid < 0) { |
36eb9bde | 678 | SYSERROR("failed to fork into a new namespace"); |
7fef7a06 | 679 | goto out_delete_net; |
0ad19a3f | 680 | } |
681 | ||
3c22086f CLG |
682 | lxc_sync_fini_child(handler); |
683 | ||
684 | if (lxc_sync_wait_child(handler, LXC_SYNC_CONFIGURE)) | |
99a6af52 | 685 | failed_before_rename = 1; |
0ad19a3f | 686 | |
692ba18f | 687 | if ((handler->cgroup = lxc_cgroup_create(name, cgroup_pattern, cgroup_meta, NULL, handler->pid)) == NULL) { |
33ad9f1a | 688 | ERROR("failed to create cgroups for '%s'", name); |
ae5c8b8e | 689 | goto out_delete_net; |
33ad9f1a | 690 | } |
e51d4895 | 691 | |
33ad9f1a | 692 | if (lxc_setup_cgroup_without_devices(handler, &handler->conf->cgroup)) { |
6031a6e5 DE |
693 | ERROR("failed to setup the cgroups for '%s'", name); |
694 | goto out_delete_net; | |
695 | } | |
696 | ||
33ad9f1a | 697 | if (lxc_cgroup_enter(handler->cgroup, handler->pid, false) < 0) |
7fef7a06 | 698 | goto out_delete_net; |
218d4250 | 699 | |
99a6af52 MN |
700 | if (failed_before_rename) |
701 | goto out_delete_net; | |
702 | ||
0ad19a3f | 703 | /* Create the network configuration */ |
d5088cf2 | 704 | if (handler->clone_flags & CLONE_NEWNET) { |
fae349da | 705 | if (lxc_assign_network(&handler->conf->network, handler->pid)) { |
82d5ae15 | 706 | ERROR("failed to create the configured network"); |
7fef7a06 | 707 | goto out_delete_net; |
82d5ae15 | 708 | } |
0ad19a3f | 709 | } |
710 | ||
f6d3e3e4 SH |
711 | /* map the container uids - the container became an invalid |
712 | * userid the moment it was cloned with CLONE_NEWUSER - this | |
713 | * call doesn't change anything immediately, but allows the | |
714 | * container to setuid(0) (0 being mapped to something else on | |
715 | * the host) later to become a valid uid again */ | |
716 | if (lxc_map_ids(&handler->conf->id_map, handler->pid)) { | |
717 | ERROR("failed to set up id mapping"); | |
718 | goto out_delete_net; | |
719 | } | |
720 | ||
544a48a0 SH |
721 | /* Tell the child to continue its initialization. we'll get |
722 | * LXC_SYNC_CGROUP when it is ready for us to setup cgroups | |
3c22086f CLG |
723 | */ |
724 | if (lxc_sync_barrier_child(handler, LXC_SYNC_POST_CONFIGURE)) | |
544a48a0 SH |
725 | goto out_delete_net; |
726 | ||
33ad9f1a | 727 | if (lxc_setup_cgroup_devices(handler, &handler->conf->cgroup)) { |
b98f7d6e SH |
728 | ERROR("failed to setup the devices cgroup for '%s'", name); |
729 | goto out_delete_net; | |
544a48a0 SH |
730 | } |
731 | ||
544a48a0 SH |
732 | /* Tell the child to complete its initialization and wait for |
733 | * it to exec or return an error. (the child will never | |
734 | * return LXC_SYNC_POST_CGROUP+1. It will either close the | |
735 | * sync pipe, causing lxc_sync_barrier_child to return | |
736 | * success, or return a different value, causing us to error | |
737 | * out). | |
738 | */ | |
739 | if (lxc_sync_barrier_child(handler, LXC_SYNC_POST_CGROUP)) | |
3c22086f | 740 | return -1; |
0ad19a3f | 741 | |
cc28d0b0 SH |
742 | if (detect_shared_rootfs()) |
743 | umount2(handler->conf->rootfs.mount, MNT_DETACH); | |
744 | ||
f6d3e3e4 SH |
745 | /* If child is in a fresh user namespace, chown his ptys for |
746 | * it */ | |
747 | if (uid_shift_ttys(handler->pid, handler->conf)) | |
748 | DEBUG("Failed to chown ptys.\n"); | |
749 | ||
23c53af9 | 750 | if (handler->ops->post_start(handler, handler->data)) |
e6126dbe MN |
751 | goto out_abort; |
752 | ||
25c2aca5 | 753 | if (lxc_set_state(name, handler, RUNNING)) { |
59eb99ba DL |
754 | ERROR("failed to set state to %s", |
755 | lxc_state2str(RUNNING)); | |
756 | goto out_abort; | |
3f21c114 | 757 | } |
22ebac19 | 758 | |
33ad9f1a | 759 | lxc_cgroup_put_meta(cgroup_meta); |
3c22086f | 760 | lxc_sync_fini(handler); |
0c547523 | 761 | |
e6126dbe | 762 | return 0; |
1ac470c0 | 763 | |
7fef7a06 | 764 | out_delete_net: |
d5088cf2 | 765 | if (handler->clone_flags & CLONE_NEWNET) |
74a2b586 | 766 | lxc_delete_network(handler); |
59eb99ba | 767 | out_abort: |
33ad9f1a | 768 | lxc_cgroup_put_meta(cgroup_meta); |
59eb99ba | 769 | lxc_abort(name, handler); |
3c22086f | 770 | lxc_sync_fini(handler); |
5c068da9 SH |
771 | if (handler->pinfd >= 0) { |
772 | close(handler->pinfd); | |
773 | handler->pinfd = -1; | |
774 | } | |
775 | ||
b79fcd86 | 776 | return -1; |
59eb99ba | 777 | } |
0ad19a3f | 778 | |
ee70bf78 | 779 | int __lxc_start(const char *name, struct lxc_conf *conf, |
13f5be62 | 780 | struct lxc_operations* ops, void *data, const char *lxcpath) |
59eb99ba | 781 | { |
3a0f472d | 782 | struct lxc_handler *handler; |
e043236e | 783 | int err = -1; |
59eb99ba | 784 | int status; |
80090207 | 785 | |
13f5be62 | 786 | handler = lxc_init(name, conf, lxcpath); |
3a0f472d | 787 | if (!handler) { |
59eb99ba | 788 | ERROR("failed to initialize the container"); |
66aeffc7 | 789 | return -1; |
0ad19a3f | 790 | } |
ee70bf78 CLG |
791 | handler->ops = ops; |
792 | handler->data = data; | |
e6126dbe | 793 | |
b60ed720 | 794 | if (must_drop_cap_sys_boot(handler->conf)) { |
495d2046 | 795 | #if HAVE_SYS_CAPABILITY_H |
f51db2b3 | 796 | DEBUG("Dropping cap_sys_boot\n"); |
495d2046 SG |
797 | #else |
798 | DEBUG("Can't drop cap_sys_boot as capabilities aren't supported\n"); | |
799 | #endif | |
69182a31 SH |
800 | } else { |
801 | DEBUG("Not dropping cap_sys_boot or watching utmp\n"); | |
802 | handler->conf->need_utmp_watch = 0; | |
803 | } | |
804 | ||
23c53af9 | 805 | err = lxc_spawn(handler); |
59eb99ba | 806 | if (err) { |
ee70bf78 | 807 | ERROR("failed to spawn '%s'", name); |
74a2b586 | 808 | goto out_fini_nonet; |
0ad19a3f | 809 | } |
810 | ||
3a0f472d | 811 | err = lxc_poll(name, handler); |
e043236e | 812 | if (err) { |
59eb99ba DL |
813 | ERROR("mainloop exited with an error"); |
814 | goto out_abort; | |
815 | } | |
0ad19a3f | 816 | |
3a0f472d | 817 | while (waitpid(handler->pid, &status, 0) < 0 && errno == EINTR) |
1bc5cc8c | 818 | continue; |
e043236e | 819 | |
8b004f07 SH |
820 | /* |
821 | * If the child process exited but was not signaled, | |
822 | * it didn't call reboot. This should mean it was an | |
823 | * lxc-execute which simply exited. In any case, treat | |
824 | * it as a 'halt' | |
825 | */ | |
826 | if (WIFSIGNALED(status)) { | |
827 | switch(WTERMSIG(status)) { | |
828 | case SIGINT: /* halt */ | |
829 | DEBUG("Container halting"); | |
830 | break; | |
831 | case SIGHUP: /* reboot */ | |
832 | DEBUG("Container rebooting"); | |
833 | handler->conf->reboot = 1; | |
834 | break; | |
835 | default: | |
836 | DEBUG("unknown exit status for init: %d\n", WTERMSIG(status)); | |
837 | break; | |
838 | } | |
828695d9 SH |
839 | } |
840 | ||
7b35f3d6 SH |
841 | lxc_rename_phys_nics_on_shutdown(handler->conf); |
842 | ||
5c068da9 SH |
843 | if (handler->pinfd >= 0) { |
844 | close(handler->pinfd); | |
845 | handler->pinfd = -1; | |
846 | } | |
847 | ||
3a0f472d | 848 | err = lxc_error_set_and_log(handler->pid, status); |
9d7f9e52 | 849 | out_fini: |
74a2b586 JK |
850 | lxc_delete_network(handler); |
851 | ||
852 | out_fini_nonet: | |
3a0f472d | 853 | lxc_fini(name, handler); |
0ad19a3f | 854 | return err; |
855 | ||
59eb99ba | 856 | out_abort: |
3a0f472d | 857 | lxc_abort(name, handler); |
9d7f9e52 | 858 | goto out_fini; |
0ad19a3f | 859 | } |
ee70bf78 CLG |
860 | |
861 | struct start_args { | |
862 | char *const *argv; | |
863 | }; | |
864 | ||
865 | static int start(struct lxc_handler *handler, void* data) | |
866 | { | |
867 | struct start_args *arg = data; | |
868 | ||
869 | NOTICE("exec'ing '%s'", arg->argv[0]); | |
870 | ||
871 | execvp(arg->argv[0], arg->argv); | |
872 | SYSERROR("failed to exec %s", arg->argv[0]); | |
873 | return 0; | |
874 | } | |
875 | ||
876 | static int post_start(struct lxc_handler *handler, void* data) | |
877 | { | |
878 | struct start_args *arg = data; | |
879 | ||
880 | NOTICE("'%s' started with pid '%d'", arg->argv[0], handler->pid); | |
881 | return 0; | |
882 | } | |
883 | ||
884 | static struct lxc_operations start_ops = { | |
885 | .start = start, | |
886 | .post_start = post_start | |
887 | }; | |
888 | ||
13f5be62 SH |
889 | int lxc_start(const char *name, char *const argv[], struct lxc_conf *conf, |
890 | const char *lxcpath) | |
ee70bf78 CLG |
891 | { |
892 | struct start_args start_arg = { | |
893 | .argv = argv, | |
894 | }; | |
895 | ||
b119f362 | 896 | if (lxc_check_inherited(conf, -1)) |
ee70bf78 CLG |
897 | return -1; |
898 | ||
828695d9 | 899 | conf->need_utmp_watch = 1; |
13f5be62 | 900 | return __lxc_start(name, conf, &start_ops, &start_arg, lxcpath); |
ee70bf78 | 901 | } |