#include <sys/un.h>
#include <sys/wait.h>
-#if HAVE_SYS_CAPABILITY_H
+#if HAVE_LIBCAP
#include <sys/capability.h>
#endif
-#if !HAVE_DECL_PR_CAPBSET_DROP
+#ifndef HAVE_DECL_PR_CAPBSET_DROP
#define PR_CAPBSET_DROP 24
#endif
+#ifndef HAVE_DECL_PR_SET_NO_NEW_PRIVS
+#define PR_SET_NO_NEW_PRIVS 38
+#endif
+
+#ifndef HAVE_DECL_PR_GET_NO_NEW_PRIVS
+#define PR_GET_NO_NEW_PRIVS 39
+#endif
+
#include "af_unix.h"
+#include "bdev.h"
#include "caps.h"
#include "cgroup.h"
#include "commands.h"
+#include "commands_utils.h"
#include "conf.h"
#include "console.h"
#include "error.h"
#include "log.h"
+#include "lxccontainer.h"
#include "lxclock.h"
#include "lxcseccomp.h"
#include "lxcutmp.h"
#include "monitor.h"
#include "namespace.h"
#include "start.h"
+#include "storage_utils.h"
#include "sync.h"
#include "utils.h"
-#include "bdev/bdev.h"
#include "lsm/lsm.h"
lxc_log_define(lxc_start, lxc);
-const struct ns_info ns_info[LXC_NS_MAX] = {
- [LXC_NS_MNT] = {"mnt", CLONE_NEWNS},
- [LXC_NS_PID] = {"pid", CLONE_NEWPID},
- [LXC_NS_UTS] = {"uts", CLONE_NEWUTS},
- [LXC_NS_IPC] = {"ipc", CLONE_NEWIPC},
- [LXC_NS_USER] = {"user", CLONE_NEWUSER},
- [LXC_NS_NET] = {"net", CLONE_NEWNET}
-};
-
extern void mod_all_rdeps(struct lxc_container *c, bool inc);
static bool do_destroy_container(struct lxc_conf *conf);
static int lxc_rmdir_onedev_wrapper(void *data);
saved = *p;
*p = '\0';
if (access(copy, X_OK)) {
- SYSERROR("could not access %s. Please grant it 'x' " \
- "access, or add an ACL for the container root.",
- copy);
+ SYSERROR("Could not access %s. Please grant it x "
+ "access, or add an ACL for the container "
+ "root.", copy);
return;
}
*p = saved;
}
}
-static void close_ns(int ns_fd[LXC_NS_MAX]) {
+static void close_ns(int ns_fd[LXC_NS_MAX])
+{
int i;
for (i = 0; i < LXC_NS_MAX; i++) {
}
}
-/*
- * preserve_ns: open /proc/@pid/ns/@ns for each namespace specified
+/* preserve_ns: open /proc/@pid/ns/@ns for each namespace specified
* in clone_flags.
- * Return true on success, false on failure. On failure, leave an error
- * message in *errmsg, which caller must free.
+ * Return true on success, false on failure.
*/
-static bool preserve_ns(int ns_fd[LXC_NS_MAX], int clone_flags, pid_t pid,
- char **errmsg)
+static bool preserve_ns(int ns_fd[LXC_NS_MAX], int clone_flags, pid_t pid)
{
int i, ret;
- char path[MAXPATHLEN];
for (i = 0; i < LXC_NS_MAX; i++)
ns_fd[i] = -1;
- snprintf(path, MAXPATHLEN, "/proc/%d/ns", pid);
- if (access(path, X_OK)) {
- if (asprintf(errmsg, "Kernel does not support setns.") == -1)
- *errmsg = NULL;
+ ret = lxc_preserve_ns(pid, "");
+ if (ret < 0) {
+ SYSERROR("Kernel does not support attaching to namespaces.");
return false;
+ } else {
+ close(ret);
}
for (i = 0; i < LXC_NS_MAX; i++) {
if ((clone_flags & ns_info[i].clone_flag) == 0)
continue;
- snprintf(path, MAXPATHLEN, "/proc/%d/ns/%s", pid,
- ns_info[i].proc_name);
- ns_fd[i] = open(path, O_RDONLY | O_CLOEXEC);
+ ns_fd[i] = lxc_preserve_ns(pid, ns_info[i].proc_name);
if (ns_fd[i] < 0)
goto error;
}
return true;
error:
- if (errno == ENOENT) {
- ret = asprintf(errmsg, "Kernel does not support setns for %s",
- ns_info[i].proc_name);
- } else {
- ret = asprintf(errmsg, "Failed to open %s: %s",
- path, strerror(errno));
- }
- if (ret == -1)
- *errmsg = NULL;
+ if (errno == ENOENT)
+ SYSERROR("Kernel does not support attaching to %s namespaces.", ns_info[i].proc_name);
+ else
+ SYSERROR("Failed to open file descriptor for %s namespace: %s.", ns_info[i].proc_name, strerror(errno));
close_ns(ns_fd);
return false;
}
return 0;
error:
- SYSERROR("failed to set namespace '%s'", ns_info[i].proc_name);
+ SYSERROR("Failed to attach %s namespace.", ns_info[i].proc_name);
return -1;
}
return (fd == 0 || fd == 1 || fd == 2);
}
-/*
- * Check for any fds we need to close
- * * if fd_to_ignore != -1, then if we find that fd open we will ignore it.
- * * By default we warn about open fds we find.
- * * If closeall is true, we will close open fds.
- * * If lxc-start was passed "-C", then conf->close_all_fds will be true,
- * in which case we also close all open fds.
- * * A daemonized container will always pass closeall=true.
- */
-int lxc_check_inherited(struct lxc_conf *conf, bool closeall, int fd_to_ignore)
+int lxc_check_inherited(struct lxc_conf *conf, bool closeall,
+ int *fds_to_ignore, size_t len_fds)
{
- struct dirent dirent, *direntp;
+ struct dirent *direntp;
int fd, fddir;
+ size_t i;
DIR *dir;
if (conf && conf->close_all_fds)
restart:
dir = opendir("/proc/self/fd");
if (!dir) {
- WARN("failed to open directory: %m");
+ WARN("Failed to open directory: %s.", strerror(errno));
return -1;
}
fddir = dirfd(dir);
- while (!readdir_r(dir, &dirent, &direntp)) {
+ while ((direntp = readdir(dir))) {
if (!direntp)
break;
if (!strcmp(direntp->d_name, ".."))
continue;
- fd = atoi(direntp->d_name);
+ if (lxc_safe_int(direntp->d_name, &fd) < 0) {
+ INFO("Could not parse file descriptor for: %s", direntp->d_name);
+ continue;
+ }
+
+ for (i = 0; i < len_fds; i++)
+ if (fds_to_ignore[i] == fd)
+ break;
- if (fd == fddir || fd == lxc_log_fd || fd == fd_to_ignore)
+ if (fd == fddir || fd == lxc_log_fd ||
+ (i < len_fds && fd == fds_to_ignore[i]))
continue;
if (current_config && fd == current_config->logfd)
if (closeall) {
close(fd);
closedir(dir);
- INFO("closed inherited fd %d", fd);
+ INFO("Closed inherited fd: %d.", fd);
goto restart;
}
- WARN("inherited fd %d", fd);
+ WARN("Inherited fd: %d.", fd);
}
+ /* Only enable syslog at this point to avoid the above logging function
+ * to open a new fd and make the check_inherited function enter an
+ * infinite loop.
+ */
+ lxc_log_enable_syslog();
+
closedir(dir); /* cannot fail */
return 0;
}
sigset_t mask;
int fd;
- /* Block everything except serious error signals */
+ /* Block everything except serious error signals. */
if (sigfillset(&mask) ||
sigdelset(&mask, SIGILL) ||
sigdelset(&mask, SIGSEGV) ||
sigdelset(&mask, SIGBUS) ||
sigdelset(&mask, SIGWINCH) ||
sigprocmask(SIG_BLOCK, &mask, oldmask)) {
- SYSERROR("failed to set signal mask");
+ SYSERROR("Failed to set signal mask.");
return -1;
}
fd = signalfd(-1, &mask, 0);
if (fd < 0) {
- SYSERROR("failed to create the signal fd");
+ SYSERROR("Failed to create signal file descriptor.");
return -1;
}
if (fcntl(fd, F_SETFD, FD_CLOEXEC)) {
- SYSERROR("failed to set sigfd to close-on-exec");
+ SYSERROR("Failed to set FD_CLOEXEC on the signal file descriptor: %d.", fd);
close(fd);
return -1;
}
- DEBUG("sigchild handler set");
+ DEBUG("Set SIGCHLD handler with file descriptor: %d.", fd);
return fd;
}
ret = read(fd, &siginfo, sizeof(siginfo));
if (ret < 0) {
- ERROR("failed to read signal info");
+ ERROR("Failed to read signal info from signal file descriptor: %d.", fd);
return -1;
}
if (ret != sizeof(siginfo)) {
- ERROR("unexpected siginfo size");
+ ERROR("Unexpected size for siginfo struct.");
return -1;
}
- // check whether init is running
+ /* Check whether init is running. */
info.si_pid = 0;
ret = waitid(P_PID, *pid, &info, WEXITED | WNOWAIT | WNOHANG);
- if (ret == 0 && info.si_pid == *pid) {
+ if (ret == 0 && info.si_pid == *pid)
init_died = true;
- }
if (siginfo.ssi_signo != SIGCHLD) {
kill(*pid, siginfo.ssi_signo);
- INFO("forwarded signal %d to pid %d", siginfo.ssi_signo, *pid);
+ INFO("Forwarded signal %d to pid %d.", siginfo.ssi_signo, *pid);
return init_died ? 1 : 0;
}
- if (siginfo.ssi_code == CLD_STOPPED ||
- siginfo.ssi_code == CLD_CONTINUED) {
- INFO("container init process was stopped/continued");
+ if (siginfo.ssi_code == CLD_STOPPED) {
+ INFO("Container init process was stopped.");
+ return init_died ? 1 : 0;
+ } else if (siginfo.ssi_code == CLD_CONTINUED) {
+ INFO("Container init process was continued.");
return init_died ? 1 : 0;
}
- /* more robustness, protect ourself from a SIGCHLD sent
- * by a process different from the container init
+ /* More robustness, protect ourself from a SIGCHLD sent
+ * by a process different from the container init.
*/
if (siginfo.ssi_pid != *pid) {
- WARN("invalid pid for SIGCHLD");
+ NOTICE("Received SIGCHLD from pid %d instead of container init %d.", siginfo.ssi_pid, *pid);
return init_died ? 1 : 0;
}
- DEBUG("container init process exited");
+ DEBUG("Container init process %d exited.", *pid);
return 1;
}
-int lxc_set_state(const char *name, struct lxc_handler *handler, lxc_state_t state)
+static int lxc_serve_state_clients(const char *name,
+ struct lxc_handler *handler,
+ lxc_state_t state)
{
+ ssize_t ret;
+ struct lxc_list *cur, *next;
+ struct state_client *client;
+ struct lxc_msg msg = {.type = lxc_msg_state, .value = state};
+
+ process_lock();
+
+ /* Only set state under process lock held so that we don't cause
+ * lxc_cmd_add_state_client() to miss a state.
+ */
handler->state = state;
+ TRACE("set container state to %s", lxc_state2str(state));
+
+ if (lxc_list_empty(&handler->state_clients)) {
+ TRACE("no state clients registered");
+ process_unlock();
+ lxc_monitor_send_state(name, state, handler->lxcpath);
+ return 0;
+ }
+
+ strncpy(msg.name, name, sizeof(msg.name));
+ msg.name[sizeof(msg.name) - 1] = 0;
+
+ lxc_list_for_each_safe(cur, &handler->state_clients, next) {
+ client = cur->elem;
+
+ if (!client->states[state]) {
+ TRACE("state %s not registered for state client %d",
+ lxc_state2str(state), client->clientfd);
+ continue;
+ }
+
+ TRACE("sending state %s to state client %d",
+ lxc_state2str(state), client->clientfd);
+
+ again:
+ ret = send(client->clientfd, &msg, sizeof(msg), 0);
+ if (ret < 0) {
+ if (errno == EINTR)
+ goto again;
+
+ ERROR("failed to send message to client");
+ }
+
+ /* kick client from list */
+ close(client->clientfd);
+ lxc_list_del(cur);
+ free(cur->elem);
+ free(cur);
+ }
+ process_unlock();
+
+ return 0;
+}
+
+static int lxc_serve_state_socket_pair(const char *name,
+ struct lxc_handler *handler,
+ lxc_state_t state)
+{
+ ssize_t ret;
+
+ if (!handler->backgrounded ||
+ handler->state_socket_pair[1] < 0 ||
+ state == STARTING)
+ return 0;
+
+ /* Close read end of the socket pair. */
+ close(handler->state_socket_pair[0]);
+ handler->state_socket_pair[0] = -1;
+
+ ret = lxc_abstract_unix_send_credential(handler->state_socket_pair[1],
+ &(int){state}, sizeof(int));
+ if (ret != sizeof(int))
+ SYSERROR("Failed to send state to %d",
+ handler->state_socket_pair[1]);
+
+ TRACE("Sent container state \"%s\" to %d", lxc_state2str(state),
+ handler->state_socket_pair[1]);
+
+ /* Close write end of the socket pair. */
+ close(handler->state_socket_pair[1]);
+ handler->state_socket_pair[1] = -1;
+
+ return 0;
+}
+
+int lxc_set_state(const char *name, struct lxc_handler *handler,
+ lxc_state_t state)
+{
+ int ret;
+
+ ret = lxc_serve_state_socket_pair(name, handler, state);
+ if (ret < 0) {
+ ERROR("Failed to synchronize via anonymous pair of unix sockets");
+ return -1;
+ }
+
+ ret = lxc_serve_state_clients(name, handler, state);
+ if (ret < 0)
+ return -1;
+
+ /* This function will try to connect to the legacy lxc-monitord state
+ * server and only exists for backwards compatibility.
+ */
lxc_monitor_send_state(name, state, handler->lxcpath);
+
return 0;
}
struct lxc_epoll_descr descr;
if (lxc_mainloop_open(&descr)) {
- ERROR("failed to create mainloop");
+ ERROR("Failed to create LXC mainloop.");
goto out_sigfd;
}
if (lxc_mainloop_add_handler(&descr, sigfd, signal_handler, &pid)) {
- ERROR("failed to add handler for the signal");
+ ERROR("Failed to add signal handler with file descriptor %d to LXC mainloop.", sigfd);
goto out_mainloop_open;
}
if (lxc_console_mainloop_add(&descr, handler->conf)) {
- ERROR("failed to add console handler to mainloop");
+ ERROR("Failed to add console handler to LXC mainloop.");
goto out_mainloop_open;
}
if (lxc_cmd_mainloop_add(name, &descr, handler)) {
- ERROR("failed to add command handler to mainloop");
+ ERROR("Failed to add command handler to LXC mainloop.");
goto out_mainloop_open;
}
if (handler->conf->need_utmp_watch) {
- #if HAVE_SYS_CAPABILITY_H
+ #if HAVE_LIBCAP
if (lxc_utmp_mainloop_add(&descr, handler)) {
- ERROR("failed to add utmp handler to mainloop");
+ ERROR("Failed to add utmp handler to LXC mainloop.");
goto out_mainloop_open;
}
#else
- DEBUG("not starting utmp handler as cap_sys_boot cannot be dropped without capabilities support");
+ DEBUG("Not starting utmp handler as CAP_SYS_BOOT cannot be dropped without capabilities support.");
#endif
}
+ TRACE("lxc mainloop is ready");
return lxc_mainloop(&descr, -1);
out_mainloop_open:
lxc_mainloop_close(&descr);
+
out_sigfd:
close(sigfd);
+
return -1;
}
-struct lxc_handler *lxc_init(const char *name, struct lxc_conf *conf, const char *lxcpath)
+void lxc_free_handler(struct lxc_handler *handler)
{
- int i;
+ if (handler->conf && handler->conf->maincmd_fd)
+ close(handler->conf->maincmd_fd);
+
+ if (handler->state_socket_pair[0] >= 0)
+ close(handler->state_socket_pair[0]);
+
+ if (handler->state_socket_pair[1] >= 0)
+ close(handler->state_socket_pair[1]);
+
+ if (handler->name)
+ free(handler->name);
+
+ handler->conf = NULL;
+ free(handler);
+}
+
+struct lxc_handler *lxc_init_handler(const char *name, struct lxc_conf *conf,
+ const char *lxcpath, bool daemonize)
+{
+ int i, ret;
struct lxc_handler *handler;
handler = malloc(sizeof(*handler));
- if (!handler)
+ if (!handler) {
+ ERROR("failed to allocate memory");
return NULL;
+ }
memset(handler, 0, sizeof(*handler));
handler->conf = conf;
handler->lxcpath = lxcpath;
handler->pinfd = -1;
+ handler->state_socket_pair[0] = handler->state_socket_pair[1] = -1;
+ lxc_list_init(&handler->state_clients);
for (i = 0; i < LXC_NS_MAX; i++)
handler->nsfd[i] = -1;
- lsm_init();
-
handler->name = strdup(name);
if (!handler->name) {
ERROR("failed to allocate memory");
- goto out_free;
+ goto on_error;
+ }
+
+ if (daemonize && !handler->conf->reboot) {
+ /* Create socketpair() to synchronize on daemonized startup.
+ * When the container reboots we don't need to synchronize again
+ * currently so don't open another socketpair().
+ */
+ ret = socketpair(AF_UNIX, SOCK_STREAM | SOCK_CLOEXEC, 0,
+ handler->state_socket_pair);
+ if (ret < 0) {
+ ERROR("Failed to create anonymous pair of unix sockets");
+ goto on_error;
+ }
+ TRACE("Created anonymous pair {%d,%d} of unix sockets",
+ handler->state_socket_pair[0],
+ handler->state_socket_pair[1]);
}
- if (lxc_cmd_init(name, handler, lxcpath))
- goto out_free_name;
+ if (lxc_cmd_init(name, handler, lxcpath)) {
+ ERROR("failed to set up command socket");
+ goto on_error;
+ }
+
+ TRACE("unix domain socket %d for command server is ready",
+ handler->conf->maincmd_fd);
+
+ return handler;
+
+on_error:
+ lxc_free_handler(handler);
+
+ return NULL;
+}
+
+int lxc_init(const char *name, struct lxc_handler *handler)
+{
+ struct lxc_conf *conf = handler->conf;
+
+ lsm_init();
+ TRACE("initialized LSM");
if (lxc_read_seccomp_config(conf) != 0) {
- ERROR("failed loading seccomp policy");
+ ERROR("Failed loading seccomp policy.");
goto out_close_maincmd_fd;
}
+ TRACE("read seccomp policy");
- /* Begin by setting the state to STARTING */
+ /* Begin by setting the state to STARTING. */
if (lxc_set_state(name, handler, STARTING)) {
- ERROR("failed to set state '%s'", lxc_state2str(STARTING));
+ ERROR("Failed to set state for container \"%s\" to \"%s\".", name, lxc_state2str(STARTING));
goto out_close_maincmd_fd;
}
+ TRACE("set container state to \"STARTING\"");
- /* Start of environment variable setup for hooks */
- if (name && setenv("LXC_NAME", name, 1)) {
- SYSERROR("failed to set environment variable for container name");
- }
- if (conf->rcfile && setenv("LXC_CONFIG_FILE", conf->rcfile, 1)) {
- SYSERROR("failed to set environment variable for config path");
- }
- if (conf->rootfs.mount && setenv("LXC_ROOTFS_MOUNT", conf->rootfs.mount, 1)) {
- SYSERROR("failed to set environment variable for rootfs mount");
- }
- if (conf->rootfs.path && setenv("LXC_ROOTFS_PATH", conf->rootfs.path, 1)) {
- SYSERROR("failed to set environment variable for rootfs mount");
- }
- if (conf->console.path && setenv("LXC_CONSOLE", conf->console.path, 1)) {
- SYSERROR("failed to set environment variable for console path");
- }
- if (conf->console.log_path && setenv("LXC_CONSOLE_LOGPATH", conf->console.log_path, 1)) {
- SYSERROR("failed to set environment variable for console log");
- }
- if (setenv("LXC_CGNS_AWARE", "1", 1)) {
- SYSERROR("failed to set LXC_CGNS_AWARE environment variable");
- }
- /* End of environment variable setup for hooks */
+ /* Start of environment variable setup for hooks. */
+ if (name && setenv("LXC_NAME", name, 1))
+ SYSERROR("Failed to set environment variable: LXC_NAME=%s.", name);
+
+ if (conf->rcfile && setenv("LXC_CONFIG_FILE", conf->rcfile, 1))
+ SYSERROR("Failed to set environment variable: LXC_CONFIG_FILE=%s.", conf->rcfile);
+
+ if (conf->rootfs.mount && setenv("LXC_ROOTFS_MOUNT", conf->rootfs.mount, 1))
+ SYSERROR("Failed to set environment variable: LXC_ROOTFS_MOUNT=%s.", conf->rootfs.mount);
+
+ if (conf->rootfs.path && setenv("LXC_ROOTFS_PATH", conf->rootfs.path, 1))
+ SYSERROR("Failed to set environment variable: LXC_ROOTFS_PATH=%s.", conf->rootfs.path);
+
+ if (conf->console.path && setenv("LXC_CONSOLE", conf->console.path, 1))
+ SYSERROR("Failed to set environment variable: LXC_CONSOLE=%s.", conf->console.path);
+
+ if (conf->console.log_path && setenv("LXC_CONSOLE_LOGPATH", conf->console.log_path, 1))
+ SYSERROR("Failed to set environment variable: LXC_CONSOLE_LOGPATH=%s.", conf->console.log_path);
+
+ if (setenv("LXC_CGNS_AWARE", "1", 1))
+ SYSERROR("Failed to set environment variable LXC_CGNS_AWARE=1.");
+ /* End of environment variable setup for hooks. */
+
+ TRACE("set environment variables");
if (run_lxc_hooks(name, "pre-start", conf, handler->lxcpath, NULL)) {
- ERROR("failed to run pre-start hooks for container '%s'.", name);
+ ERROR("Failed to run lxc.hook.pre-start for container \"%s\".", name);
goto out_aborting;
}
+ TRACE("ran pre-start hooks");
- /* the signal fd has to be created before forking otherwise
- * if the child process exits before we setup the signal fd,
- * the event will be lost and the command will be stuck */
+ /* The signal fd has to be created before forking otherwise if the child
+ * process exits before we setup the signal fd, the event will be lost
+ * and the command will be stuck.
+ */
handler->sigfd = setup_signal_fd(&handler->oldmask);
if (handler->sigfd < 0) {
- ERROR("failed to set sigchild fd handler");
+ ERROR("Failed to setup SIGCHLD fd handler.");
goto out_delete_tty;
}
+ TRACE("set up signal fd");
- /* do this after setting up signals since it might unblock SIGWINCH */
+ /* Do this after setting up signals since it might unblock SIGWINCH. */
if (lxc_console_create(conf)) {
- ERROR("failed to create console");
+ ERROR("Failed to create console for container \"%s\".", name);
goto out_restore_sigmask;
}
+ TRACE("created console");
- if (ttys_shift_ids(conf) < 0) {
- ERROR("Failed to shift tty into container");
+ if (lxc_ttys_shift_ids(conf) < 0) {
+ ERROR("Failed to shift tty into container.");
goto out_restore_sigmask;
}
+ TRACE("shifted tty ids");
- INFO("'%s' is initialized", name);
- return handler;
+ INFO("container \"%s\" is initialized", name);
+ return 0;
out_restore_sigmask:
sigprocmask(SIG_SETMASK, &handler->oldmask, NULL);
out_close_maincmd_fd:
close(conf->maincmd_fd);
conf->maincmd_fd = -1;
-out_free_name:
- free(handler->name);
- handler->name = NULL;
-out_free:
- free(handler);
- return NULL;
+ return -1;
}
void lxc_fini(const char *name, struct lxc_handler *handler)
{
int i, rc;
+ struct lxc_list *cur, *next;
pid_t self = getpid();
- char *namespaces[LXC_NS_MAX+1];
+ char *namespaces[LXC_NS_MAX + 1];
size_t namespace_count = 0;
- /* The STOPPING state is there for future cleanup code
- * which can take awhile
+ /* The STOPPING state is there for future cleanup code which can take
+ * awhile.
*/
lxc_set_state(name, handler, STOPPING);
rc = asprintf(&namespaces[namespace_count], "%s:/proc/%d/fd/%d",
ns_info[i].proc_name, self, handler->nsfd[i]);
if (rc == -1) {
- SYSERROR("failed to allocate memory");
+ SYSERROR("Failed to allocate memory.");
break;
}
++namespace_count;
}
namespaces[namespace_count] = NULL;
- if (handler->conf->reboot && setenv("LXC_TARGET", "reboot", 1)) {
- SYSERROR("failed to set environment variable for stop target");
- }
- if (!handler->conf->reboot && setenv("LXC_TARGET", "stop", 1)) {
- SYSERROR("failed to set environment variable for stop target");
- }
+ if (handler->conf->reboot && setenv("LXC_TARGET", "reboot", 1))
+ SYSERROR("Failed to set environment variable: LXC_TARGET=reboot.");
+
+ if (!handler->conf->reboot && setenv("LXC_TARGET", "stop", 1))
+ SYSERROR("Failed to set environment variable: LXC_TARGET=stop.");
if (run_lxc_hooks(name, "stop", handler->conf, handler->lxcpath, namespaces))
- ERROR("failed to run stop hooks for container '%s'.", name);
+ ERROR("Failed to run lxc.hook.stop for container \"%s\".", name);
while (namespace_count--)
free(namespaces[namespace_count]);
handler->nsfd[i] = -1;
}
}
+
+ if (handler->netnsfd >= 0) {
+ close(handler->netnsfd);
+ handler->netnsfd = -1;
+ }
+
lxc_set_state(name, handler, STOPPED);
if (run_lxc_hooks(name, "post-stop", handler->conf, handler->lxcpath, NULL)) {
- ERROR("failed to run post-stop hooks for container '%s'.", name);
+ ERROR("Failed to run lxc.hook.post-stop for container \"%s\".", name);
if (handler->conf->reboot) {
WARN("Container will be stopped instead of rebooted.");
handler->conf->reboot = 0;
- setenv("LXC_TARGET", "stop", 1);
+ if (setenv("LXC_TARGET", "stop", 1))
+ WARN("Failed to set environment variable: LXC_TARGET=stop.");
}
}
- /* reset mask set by setup_signal_fd */
+ /* Reset mask set by setup_signal_fd. */
if (sigprocmask(SIG_SETMASK, &handler->oldmask, NULL))
- WARN("failed to restore sigprocmask");
+ WARN("Failed to restore signal mask.");
lxc_console_delete(&handler->conf->console);
lxc_delete_tty(&handler->conf->tty_info);
+
+ /* close the command socket */
close(handler->conf->maincmd_fd);
handler->conf->maincmd_fd = -1;
+
+ /* The command socket is now closed, no more state clients can register
+ * themselves from now on. So free the list of state clients.
+ */
+ lxc_list_for_each_safe(cur, &handler->state_clients, next) {
+ struct state_client *client = cur->elem;
+ /* close state client socket */
+ close(client->clientfd);
+ lxc_list_del(cur);
+ free(cur->elem);
+ free(cur);
+ }
+
free(handler->name);
if (handler->ttysock[0] != -1) {
close(handler->ttysock[0]);
lxc_set_state(name, handler, ABORTING);
if (handler->pid > 0)
kill(handler->pid, SIGKILL);
- while ((ret = waitpid(-1, &status, 0)) > 0) ;
+ while ((ret = waitpid(-1, &status, 0)) > 0) {
+ ;
+ }
}
#include <sys/reboot.h>
#include <linux/reboot.h>
-/*
- * reboot(LINUX_REBOOT_CMD_CAD_ON) will return -EINVAL
- * in a child pid namespace if container reboot support exists.
- * Otherwise, it will either succeed or return -EPERM.
+/* reboot(LINUX_REBOOT_CMD_CAD_ON) will return -EINVAL in a child pid namespace
+ * if container reboot support exists. Otherwise, it will either succeed or
+ * return -EPERM.
*/
static int container_reboot_supported(void *arg)
{
ret = fscanf(f, "%d", &v);
fclose(f);
if (ret != 1) {
- DEBUG("Failed to read /proc/sys/kernel/ctrl-alt-del");
+ DEBUG("Failed to read /proc/sys/kernel/ctrl-alt-del.");
return 1;
}
cmd = v ? LINUX_REBOOT_CMD_CAD_ON : LINUX_REBOOT_CMD_CAD_OFF;
#endif
if (pid < 0) {
if (flags & CLONE_NEWUSER)
- ERROR("failed to clone (%#x): %s (includes CLONE_NEWUSER)", flags, strerror(errno));
+ ERROR("Failed to clone (%#x): %s (includes CLONE_NEWUSER).", flags, strerror(errno));
else
- ERROR("failed to clone (%#x): %s", flags, strerror(errno));
+ ERROR("Failed to clone (%#x): %s.", flags, strerror(errno));
return -1;
}
if (wait(&status) < 0) {
- SYSERROR("unexpected wait error: %m");
+ SYSERROR("Unexpected wait error: %s.", strerror(errno));
return -1;
}
return 0;
}
-/*
- * netpipe is used in the unprivileged case to transfer the ifindexes
- * from parent to child
+/* netpipe is used in the unprivileged case to transfer the ifindexes from
+ * parent to child
*/
static int netpipe = -1;
if (netdev->type != LXC_NET_VETH)
continue;
if (!(netdev->name = malloc(IFNAMSIZ))) {
- ERROR("Out of memory");
+ ERROR("Out of memory.");
close(netpipe);
return -1;
}
char path[PATH_MAX];
if (sigprocmask(SIG_SETMASK, &handler->oldmask, NULL)) {
- SYSERROR("failed to set sigprocmask");
+ SYSERROR("Failed to set signal mask.");
return -1;
}
- /* This prctl must be before the synchro, so if the parent
- * dies before we set the parent death signal, we will detect
- * its death with the synchro right after, otherwise we have
- * a window where the parent can exit before we set the pdeath
- * signal leading to a unsupervized container.
+ /* This prctl must be before the synchro, so if the parent dies before
+ * we set the parent death signal, we will detect its death with the
+ * synchro right after, otherwise we have a window where the parent can
+ * exit before we set the pdeath signal leading to a unsupervized
+ * container.
*/
if (prctl(PR_SET_PDEATHSIG, SIGKILL, 0, 0, 0)) {
- SYSERROR("failed to set pdeath signal");
+ SYSERROR("Failed to set PR_SET_PDEATHSIG to SIGKILL.");
return -1;
}
lxc_sync_fini_parent(handler);
- /* don't leak the pinfd to the container */
+ /* Don't leak the pinfd to the container. */
if (handler->pinfd >= 0) {
close(handler->pinfd);
}
if (lxc_sync_wait_parent(handler, LXC_SYNC_STARTUP))
return -1;
- /* Unshare CLONE_NEWNET after CLONE_NEWUSER - see
- https://github.com/lxc/lxd/issues/1978 */
+ /* Unshare CLONE_NEWNET after CLONE_NEWUSER. See
+ * https://github.com/lxc/lxd/issues/1978.
+ */
if ((handler->clone_flags & (CLONE_NEWNET | CLONE_NEWUSER)) ==
- (CLONE_NEWNET | CLONE_NEWUSER)) {
+ (CLONE_NEWNET | CLONE_NEWUSER)) {
ret = unshare(CLONE_NEWNET);
if (ret < 0) {
- SYSERROR("Error unsharing network namespace");
+ SYSERROR("Failed to unshare CLONE_NEWNET.");
goto out_warn_father;
}
+ INFO("Unshared CLONE_NEWNET.");
}
- /* Tell the parent task it can begin to configure the
- * container and wait for it to finish
+ /* Tell the parent task it can begin to configure the container and wait
+ * for it to finish.
*/
if (lxc_sync_barrier_parent(handler, LXC_SYNC_CONFIGURE))
return -1;
if (read_unpriv_netifindex(&handler->conf->network) < 0)
goto out_warn_father;
- /*
- * if we are in a new user namespace, become root there to have
- * privilege over our namespace. When using lxc-execute we default to root,
- * but this can be overriden using the lxc.init_uid and lxc.init_gid
- * configuration options.
+ /* If we are in a new user namespace, become root there to have
+ * privilege over our namespace.
*/
if (!lxc_list_empty(&handler->conf->id_map)) {
- gid_t new_gid = 0;
- if (handler->conf->is_execute && handler->conf->init_gid)
- new_gid = handler->conf->init_gid;
-
- uid_t new_uid = 0;
- if (handler->conf->is_execute && handler->conf->init_uid)
- new_uid = handler->conf->init_uid;
-
- NOTICE("switching to gid/uid %d/%d in new user namespace", new_gid, new_uid);
- if (setgid(new_gid)) {
- SYSERROR("setgid");
+ if (lxc_switch_uid_gid(0, 0) < 0)
goto out_warn_father;
- }
- if (setuid(new_uid)) {
- SYSERROR("setuid");
- goto out_warn_father;
- }
- if (setgroups(0, NULL)) {
- SYSERROR("setgroups");
+
+ /* Drop groups only after we switched to a valid gid in the new
+ * user namespace.
+ */
+ if (lxc_setgroups(0, NULL) < 0)
goto out_warn_father;
- }
}
if (access(handler->lxcpath, X_OK)) {
goto out_warn_father;
}
- #if HAVE_SYS_CAPABILITY_H
+ #if HAVE_LIBCAP
if (handler->conf->need_utmp_watch) {
if (prctl(PR_CAPBSET_DROP, CAP_SYS_BOOT, 0, 0, 0)) {
- SYSERROR("failed to remove CAP_SYS_BOOT capability");
+ SYSERROR("Failed to remove the CAP_SYS_BOOT capability.");
goto out_warn_father;
}
- DEBUG("Dropped cap_sys_boot");
+ DEBUG("Dropped the CAP_SYS_BOOT capability.");
}
#endif
ret = snprintf(path, sizeof(path), "%s/dev/null", handler->conf->rootfs.mount);
- if (ret < 0 || ret >= sizeof(path)) {
- SYSERROR("sprintf'd too many chars");
+ if (ret < 0 || ret >= sizeof(path))
goto out_warn_father;
- }
/* In order to checkpoint restore, we need to have everything in the
* same mount namespace. However, some containers may not have a
if (devnull_fd < 0)
goto out_warn_father;
- WARN("using host's /dev/null for container init's std fds, migraiton won't work");
+ WARN("Using /dev/null from the host for container init's "
+ "standard file descriptors. Migration will not work.");
}
/* Setup the container, ip, names, utsname, ... */
if (lxc_setup(handler)) {
- ERROR("failed to setup the container");
+ ERROR("Failed to setup container \"%s\".", handler->name);
goto out_warn_father;
}
- /* ask father to setup cgroups and wait for him to finish */
+ /* Ask father to setup cgroups and wait for him to finish. */
if (lxc_sync_barrier_parent(handler, LXC_SYNC_CGROUP))
goto out_error;
- /* Set the label to change to when we exec(2) the container's init */
+ /* Unshare cgroup namespace after we have setup our cgroups. If we do it
+ * earlier we end up with a wrong view of /proc/self/cgroup. For
+ * example, assume we unshare(CLONE_NEWCGROUP) first, and then create
+ * the cgroup for the container, say /sys/fs/cgroup/cpuset/lxc/c, then
+ * /proc/self/cgroup would show us:
+ *
+ * 8:cpuset:/lxc/c
+ *
+ * whereas it should actually show
+ *
+ * 8:cpuset:/
+ */
+ if (cgns_supported()) {
+ if (unshare(CLONE_NEWCGROUP) < 0) {
+ INFO("Failed to unshare CLONE_NEWCGROUP.");
+ goto out_warn_father;
+ }
+ INFO("Unshared CLONE_NEWCGROUP.");
+ }
+
+ /* Set the label to change to when we exec(2) the container's init. */
if (lsm_process_label_set(NULL, handler->conf, 1, 1) < 0)
goto out_warn_father;
+ /* Set PR_SET_NO_NEW_PRIVS after we changed the lsm label. If we do it
+ * before we aren't allowed anymore.
+ */
+ if (handler->conf->no_new_privs) {
+ if (prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0) < 0) {
+ SYSERROR("Could not set PR_SET_NO_NEW_PRIVS to block execve() gainable privileges.");
+ goto out_warn_father;
+ }
+ DEBUG("Set PR_SET_NO_NEW_PRIVS to block execve() gainable privileges.");
+ }
+
/* Some init's such as busybox will set sane tty settings on stdin,
* stdout, stderr which it thinks is the console. We already set them
* the way we wanted on the real terminal, and we want init to do its
- * setup on its console ie. the pty allocated in lxc_console_create()
- * so make sure that that pty is stdin,stdout,stderr.
+ * setup on its console ie. the pty allocated in lxc_console_create() so
+ * make sure that that pty is stdin,stdout,stderr.
*/
if (lxc_console_set_stdfds(handler->conf->console.slave) < 0)
goto out_warn_father;
- /* If we mounted a temporary proc, then unmount it now */
+ /* If we mounted a temporary proc, then unmount it now. */
tmp_proc_unmount(handler->conf);
if (lxc_seccomp_load(handler->conf) != 0)
goto out_warn_father;
if (run_lxc_hooks(handler->name, "start", handler->conf, handler->lxcpath, NULL)) {
- ERROR("failed to run start hooks for container '%s'.", handler->name);
+ ERROR("Failed to run lxc.hook.start for container \"%s\".", handler->name);
goto out_warn_father;
}
- /* The clearenv() and putenv() calls have been moved here
- * to allow us to use environment variables passed to the various
- * hooks, such as the start hook above. Not all of the
- * variables like CONFIG_PATH or ROOTFS are valid in this
- * context but others are. */
+ /* The container has been setup. We can now switch to an unprivileged
+ * uid/gid.
+ */
+ if (handler->conf->is_execute) {
+ bool have_cap_setgid;
+ uid_t new_uid = handler->conf->init_uid;
+ gid_t new_gid = handler->conf->init_gid;
+
+ /* If we are in a new user namespace we already dropped all
+ * groups when we switched to root in the new user namespace
+ * further above. Only drop groups if we can, so ensure that we
+ * have necessary privilege.
+ */
+ #if HAVE_LIBCAP
+ have_cap_setgid = lxc_proc_cap_is_set(CAP_SETGID, CAP_EFFECTIVE);
+ #else
+ have_cap_setgid = false;
+ #endif
+ if (lxc_list_empty(&handler->conf->id_map) && have_cap_setgid) {
+ if (lxc_setgroups(0, NULL) < 0)
+ goto out_warn_father;
+ }
+
+ if (lxc_switch_uid_gid(new_uid, new_gid) < 0)
+ goto out_warn_father;
+ }
+
+ /* The clearenv() and putenv() calls have been moved here to allow us to
+ * use environment variables passed to the various hooks, such as the
+ * start hook above. Not all of the variables like CONFIG_PATH or ROOTFS
+ * are valid in this context but others are.
+ */
if (clearenv()) {
- SYSERROR("failed to clear environment");
- /* don't error out though */
+ SYSERROR("Failed to clear environment.");
+ /* Don't error out though. */
}
lxc_list_for_each(iterator, &handler->conf->environment) {
if (putenv((char *)iterator->elem)) {
- SYSERROR("failed to set environment variable '%s'", (char *)iterator->elem);
+ SYSERROR("Failed to set environment variable: %s.", (char *)iterator->elem);
goto out_warn_father;
}
}
if (putenv("container=lxc")) {
- SYSERROR("failed to set environment variable 'container=lxc'");
+ SYSERROR("Failed to set environment variable: container=lxc.");
goto out_warn_father;
}
if (handler->conf->pty_names) {
if (putenv(handler->conf->pty_names)) {
- SYSERROR("failed to set environment variable for container ptys");
+ SYSERROR("Failed to set environment variable for container ptys.");
goto out_warn_father;
}
}
setsid();
- /* after this call, we are in error because this
- * ops should not return as it execs */
+ /* After this call, we are in error because this ops should not return
+ * as it execs.
+ */
handler->ops->start(handler, handler->data);
out_warn_father:
- /* we want the parent to know something went wrong, so we return a special
- * error code. */
+ /* We want the parent to know something went wrong, so we return a
+ * special error code.
+ */
lxc_sync_wake_parent(handler, LXC_SYNC_ERROR);
out_error:
continue;
conf->saved_nics = realloc(conf->saved_nics,
(conf->num_savednics+1)*sizeof(struct saved_nic));
- if (!conf->saved_nics) {
- SYSERROR("failed to allocate memory");
+ if (!conf->saved_nics)
return -1;
- }
conf->saved_nics[conf->num_savednics].ifindex = netdev->ifindex;
conf->saved_nics[conf->num_savednics].orig_name = strdup(netdev->link);
- if (!conf->saved_nics[conf->num_savednics].orig_name) {
- SYSERROR("failed to allocate memory");
+ if (!conf->saved_nics[conf->num_savednics].orig_name)
return -1;
- }
- INFO("stored saved_nic #%d idx %d name %s", conf->num_savednics,
+ INFO("Stored saved_nic #%d idx %d name %s.", conf->num_savednics,
conf->saved_nics[conf->num_savednics].ifindex,
conf->saved_nics[conf->num_savednics].orig_name);
conf->num_savednics++;
return 0;
}
-static int recv_fd(int sock, int *fd)
-{
- if (lxc_abstract_unix_recv_fd(sock, fd, NULL, 0) < 0) {
- SYSERROR("Error receiving tty fd from child");
- return -1;
- }
- if (*fd == -1)
- return -1;
- return 0;
-}
-
-static int recv_ttys_from_child(struct lxc_handler *handler)
+static int lxc_recv_ttys_from_child(struct lxc_handler *handler)
{
+ int i;
+ int *ttyfds;
+ struct lxc_pty_info *pty_info;
+ int ret = -1;
+ int sock = handler->ttysock[1];
struct lxc_conf *conf = handler->conf;
- int i, sock = handler->ttysock[1];
struct lxc_tty_info *tty_info = &conf->tty_info;
+ size_t num_ttyfds = (2 * conf->tty);
if (!conf->tty)
return 0;
- tty_info->pty_info = malloc(sizeof(*tty_info->pty_info)*conf->tty);
- if (!tty_info->pty_info) {
- SYSERROR("failed to allocate pty_info");
+ tty_info->pty_info = malloc(sizeof(*tty_info->pty_info) * conf->tty);
+ if (!tty_info->pty_info)
+ return -1;
+
+ ttyfds = malloc(num_ttyfds * sizeof(int));
+ if (!ttyfds)
return -1;
- }
- for (i = 0; i < conf->tty; i++) {
- struct lxc_pty_info *pty_info = &tty_info->pty_info[i];
+ ret = lxc_abstract_unix_recv_fds(sock, ttyfds, num_ttyfds, NULL, 0);
+ for (i = 0; (ret >= 0 && *ttyfds != -1) && (i < num_ttyfds); i++) {
+ pty_info = &tty_info->pty_info[i / 2];
pty_info->busy = 0;
- if (recv_fd(sock, &pty_info->slave) < 0 ||
- recv_fd(sock, &pty_info->master) < 0) {
- ERROR("Error receiving tty info from child");
- return -1;
- }
+ pty_info->slave = ttyfds[i++];
+ pty_info->master = ttyfds[i];
+ TRACE("received pty with master fd %d and slave fd %d from "
+ "parent", pty_info->master, pty_info->slave);
}
+
tty_info->nbtty = conf->tty;
- return 0;
+ free(ttyfds);
+
+ if (ret < 0)
+ ERROR("failed to receive %d ttys from child: %s", conf->tty,
+ strerror(errno));
+ else
+ TRACE("received %d ttys from child", conf->tty);
+
+ return ret;
}
void resolve_clone_flags(struct lxc_handler *handler)
{
handler->clone_flags = CLONE_NEWPID | CLONE_NEWNS;
- if (!lxc_list_empty(&handler->conf->id_map)) {
- INFO("Cloning a new user namespace");
+ if (!lxc_list_empty(&handler->conf->id_map))
handler->clone_flags |= CLONE_NEWUSER;
- }
if (handler->conf->inherit_ns_fd[LXC_NS_NET] == -1) {
if (!lxc_requests_empty_network(handler))
handler->clone_flags |= CLONE_NEWNET;
} else {
- INFO("Inheriting a net namespace");
+ INFO("Inheriting a NET namespace.");
}
- if (handler->conf->inherit_ns_fd[LXC_NS_IPC] == -1) {
+ if (handler->conf->inherit_ns_fd[LXC_NS_IPC] == -1)
handler->clone_flags |= CLONE_NEWIPC;
- } else {
- INFO("Inheriting an IPC namespace");
- }
+ else
+ INFO("Inheriting an IPC namespace.");
- if (handler->conf->inherit_ns_fd[LXC_NS_UTS] == -1) {
+ if (handler->conf->inherit_ns_fd[LXC_NS_UTS] == -1)
handler->clone_flags |= CLONE_NEWUTS;
- } else {
- INFO("Inheriting a UTS namespace");
- }
+ else
+ INFO("Inheriting a UTS namespace.");
}
+/* lxc_spawn() performs crucial setup tasks and clone()s the new process which
+ * exec()s the requested container binary.
+ * Note that lxc_spawn() runs in the parent namespaces. Any operations performed
+ * right here should be double checked if they'd pose a security risk. (For
+ * example, any {u}mount() operations performed here will be reflected on the
+ * host!)
+ */
static int lxc_spawn(struct lxc_handler *handler)
{
int failed_before_rename = 0;
const char *name = handler->name;
- char *errmsg = NULL;
bool cgroups_connected = false;
int saved_ns_fd[LXC_NS_MAX];
int preserve_mask = 0, i, flags;
int netpipepair[2], nveths;
+ bool wants_to_map_ids;
+ struct lxc_list *id_map;
netpipe = -1;
+ id_map = &handler->conf->id_map;
+ wants_to_map_ids = !lxc_list_empty(id_map);
for (i = 0; i < LXC_NS_MAX; i++)
if (handler->conf->inherit_ns_fd[i] != -1)
/* Find gateway addresses from the link device, which is
* no longer accessible inside the container. Do this
* before creating network interfaces, since goto
- * out_delete_net does not work before lxc_clone. */
+ * out_delete_net does not work before lxc_clone.
+ */
if (lxc_find_gateway_addresses(handler)) {
- ERROR("failed to find gateway addresses");
+ ERROR("Failed to find gateway addresses.");
lxc_sync_fini(handler);
return -1;
}
- /* that should be done before the clone because we will
- * fill the netdev index and use them in the child
+ /* That should be done before the clone because we will
+ * fill the netdev index and use them in the child.
*/
- if (lxc_create_network(handler)) {
- ERROR("failed to create the network");
+ if (lxc_setup_networks_in_parent_namespaces(handler)) {
+ ERROR("Failed to create the network.");
lxc_sync_fini(handler);
return -1;
}
}
if (save_phys_nics(handler->conf)) {
- ERROR("failed to save physical nic info");
+ ERROR("Failed to save physical nic info.");
goto out_abort;
}
}
if (!cgroup_init(handler)) {
- ERROR("failed initializing cgroup support");
+ ERROR("Failed initializing cgroup support.");
goto out_delete_net;
}
cgroups_connected = true;
if (!cgroup_create(handler)) {
- ERROR("failed creating cgroups");
+ ERROR("Failed creating cgroups.");
goto out_delete_net;
}
- /*
- * if the rootfs is not a blockdev, prevent the container from
- * marking it readonly.
- *
- * if the container is unprivileged then skip rootfs pinning
+ /* If the rootfs is not a blockdev, prevent the container from marking
+ * it readonly.
+ * If the container is unprivileged then skip rootfs pinning.
*/
- if (lxc_list_empty(&handler->conf->id_map)) {
+ if (!wants_to_map_ids) {
handler->pinfd = pin_rootfs(handler->conf->rootfs.path);
if (handler->pinfd == -1)
- INFO("failed to pin the container's rootfs");
+ INFO("Failed to pin the rootfs for container \"%s\".", handler->name);
}
- if (!preserve_ns(saved_ns_fd, preserve_mask, getpid(), &errmsg)) {
- SYSERROR("Failed to preserve requested namespaces: %s",
- errmsg ? errmsg : "(Out of memory)");
- free(errmsg);
+ if (!preserve_ns(saved_ns_fd, preserve_mask, getpid()))
goto out_delete_net;
- }
+
if (attach_ns(handler->conf->inherit_ns_fd) < 0)
goto out_delete_net;
if (am_unpriv() && (nveths = count_veths(&handler->conf->network))) {
if (pipe(netpipepair) < 0) {
- SYSERROR("Error creating pipe");
+ SYSERROR("Failed to create pipe.");
goto out_delete_net;
}
- /* store netpipe in the global var for do_start's use */
+ /* Store netpipe in the global var for do_start's use. */
netpipe = netpipepair[0];
}
- /* Create a process in a new set of namespaces */
+ /* Create a process in a new set of namespaces. */
flags = handler->clone_flags;
- if (handler->clone_flags & CLONE_NEWUSER)
+ if (handler->clone_flags & CLONE_NEWUSER) {
+ /* If CLONE_NEWUSER and CLONE_NEWNET was requested, we need to
+ * clone a new user namespace first and only later unshare our
+ * network namespace to ensure that network devices ownership is
+ * set up correctly.
+ */
flags &= ~CLONE_NEWNET;
- if (cgns_supported()) {
- handler->clone_flags |= CLONE_NEWCGROUP;
- flags |= CLONE_NEWCGROUP;
}
handler->pid = lxc_clone(do_start, handler, flags);
if (handler->pid < 0) {
- SYSERROR("failed to fork into a new namespace");
+ SYSERROR("Failed to clone a new set of namespaces.");
goto out_delete_net;
}
+ for (i = 0; i < LXC_NS_MAX; i++)
+ if (flags & ns_info[i].clone_flag)
+ INFO("Cloned %s.", ns_info[i].flag_name);
- if (!preserve_ns(handler->nsfd, handler->clone_flags | preserve_mask, handler->pid, &errmsg)) {
- INFO("Failed to store namespace references for stop hook: %s",
- errmsg ? errmsg : "(Out of memory)");
- free(errmsg);
- }
+ if (!preserve_ns(handler->nsfd, handler->clone_flags | preserve_mask, handler->pid))
+ INFO("Failed to preserve namespace for lxc.hook.stop.");
if (attach_ns(saved_ns_fd))
- WARN("failed to restore saved namespaces");
+ WARN("Failed to restore saved namespaces.");
lxc_sync_fini_child(handler);
- /* map the container uids - the container became an invalid
- * userid the moment it was cloned with CLONE_NEWUSER - this
- * call doesn't change anything immediately, but allows the
- * container to setuid(0) (0 being mapped to something else on
- * the host) later to become a valid uid again */
- if (lxc_map_ids(&handler->conf->id_map, handler->pid)) {
- ERROR("failed to set up id mapping");
+ /* Map the container uids. The container became an invalid userid the
+ * moment it was cloned with CLONE_NEWUSER. This call doesn't change
+ * anything immediately, but allows the container to setuid(0) (0 being
+ * mapped to something else on the host.) later to become a valid uid
+ * again.
+ */
+ if (wants_to_map_ids && lxc_map_ids(id_map, handler->pid)) {
+ ERROR("Failed to set up id mapping.");
goto out_delete_net;
}
}
if (!cgroup_create_legacy(handler)) {
- ERROR("failed to setup the legacy cgroups for %s", name);
+ ERROR("Failed to setup legacy cgroups for container \"%s\".", name);
goto out_delete_net;
}
if (!cgroup_setup_limits(handler, false)) {
- ERROR("failed to setup the cgroup limits for '%s'", name);
+ ERROR("Failed to setup cgroup limits for container \"%s\".", name);
goto out_delete_net;
}
if (failed_before_rename)
goto out_delete_net;
- /* Create the network configuration */
+ /* Create the network configuration. */
if (handler->clone_flags & CLONE_NEWNET) {
if (lxc_assign_network(handler->lxcpath, handler->name,
- &handler->conf->network, handler->pid)) {
- ERROR("failed to create the configured network");
+ &handler->conf->network, handler->pid)) {
+ ERROR("Failed to create the configured network.");
goto out_delete_net;
}
}
if (netdev->type != LXC_NET_VETH)
continue;
if (write(netpipepair[1], netdev->name, IFNAMSIZ) != IFNAMSIZ) {
- ERROR("Error writing veth name to container");
+ ERROR("Error writing veth name to container.");
goto out_delete_net;
}
}
close(netpipepair[1]);
}
- /* Tell the child to continue its initialization. we'll get
- * LXC_SYNC_CGROUP when it is ready for us to setup cgroups
+ /* Tell the child to continue its initialization. We'll get
+ * LXC_SYNC_CGROUP when it is ready for us to setup cgroups.
*/
if (lxc_sync_barrier_child(handler, LXC_SYNC_POST_CONFIGURE))
goto out_delete_net;
+ if (!lxc_list_empty(&handler->conf->limits) && setup_resource_limits(&handler->conf->limits, handler->pid)) {
+ ERROR("failed to setup resource limits for '%s'", name);
+ goto out_delete_net;
+ }
+
if (!cgroup_setup_limits(handler, true)) {
- ERROR("failed to setup the devices cgroup for '%s'", name);
+ ERROR("Failed to setup the devices cgroup for container \"%s\".", name);
goto out_delete_net;
}
cgroup_disconnect();
cgroups_connected = false;
- /* read tty fds allocated by child */
- if (recv_ttys_from_child(handler) < 0) {
- ERROR("failed to receive tty info from child");
+ /* Read tty fds allocated by child. */
+ if (lxc_recv_ttys_from_child(handler) < 0) {
+ ERROR("Failed to receive tty info from child process.");
goto out_delete_net;
}
- /* Tell the child to complete its initialization and wait for
- * it to exec or return an error. (the child will never
- * return LXC_SYNC_POST_CGROUP+1. It will either close the
- * sync pipe, causing lxc_sync_barrier_child to return
- * success, or return a different value, causing us to error
- * out).
+ /* Tell the child to complete its initialization and wait for it to exec
+ * or return an error. (The child will never return
+ * LXC_SYNC_POST_CGROUP+1. It will either close the sync pipe, causing
+ * lxc_sync_barrier_child to return success, or return a different
+ * value, causing us to error out).
*/
if (lxc_sync_barrier_child(handler, LXC_SYNC_POST_CGROUP))
return -1;
- if (detect_shared_rootfs())
- umount2(handler->conf->rootfs.mount, MNT_DETACH);
-
if (handler->ops->post_start(handler, handler->data))
goto out_abort;
if (lxc_set_state(name, handler, RUNNING)) {
- ERROR("failed to set state to %s",
- lxc_state2str(RUNNING));
+ ERROR("Failed to set state for container \"%s\" to \"%s\".", name,
+ lxc_state2str(RUNNING));
goto out_abort;
}
lxc_sync_fini(handler);
+ handler->netnsfd = lxc_preserve_ns(handler->pid, "net");
return 0;
return -1;
}
-int get_netns_fd(int pid)
-{
- char path[MAXPATHLEN];
- int ret, fd;
-
- ret = snprintf(path, MAXPATHLEN, "/proc/%d/ns/net", pid);
- if (ret < 0 || ret >= MAXPATHLEN) {
- WARN("Failed to pin netns file for pid %d", pid);
- return -1;
- }
-
- fd = open(path, O_RDONLY);
- if (fd < 0) {
- WARN("Failed to pin netns file %s for pid %d: %s",
- path, pid, strerror(errno));
- return -1;
- }
- return fd;
-}
-
-int __lxc_start(const char *name, struct lxc_conf *conf,
+int __lxc_start(const char *name, struct lxc_handler *handler,
struct lxc_operations* ops, void *data, const char *lxcpath,
bool backgrounded)
{
- struct lxc_handler *handler;
- int err = -1;
int status;
- int netnsfd = -1;
+ int err = -1;
+ bool removed_all_netdevs = true;
+ struct lxc_conf *conf = handler->conf;
- handler = lxc_init(name, conf, lxcpath);
- if (!handler) {
- ERROR("failed to initialize the container");
+ if (lxc_init(name, handler) < 0) {
+ ERROR("Failed to initialize container \"%s\".", name);
return -1;
}
handler->ops = ops;
handler->data = data;
handler->backgrounded = backgrounded;
+ handler->netnsfd = -1;
if (must_drop_cap_sys_boot(handler->conf)) {
- #if HAVE_SYS_CAPABILITY_H
- DEBUG("Dropping cap_sys_boot");
+ #if HAVE_LIBCAP
+ DEBUG("Dropping CAP_SYS_BOOT capability.");
#else
- DEBUG("Can't drop cap_sys_boot as capabilities aren't supported");
+ DEBUG("Not dropping CAP_SYS_BOOT capability as capabilities aren't supported.");
#endif
} else {
- DEBUG("Not dropping cap_sys_boot or watching utmp");
+ DEBUG("Not dropping CAP_SYS_BOOT or watching utmp.");
handler->conf->need_utmp_watch = 0;
}
if (!attach_block_device(handler->conf)) {
- ERROR("Failure attaching block device");
+ ERROR("Failed to attach block device.");
goto out_fini_nonet;
}
if (geteuid() == 0 && !lxc_list_empty(&conf->id_map)) {
- /* if the backing store is a device, mount it here and now */
+ /* If the backing store is a device, mount it here and now. */
if (rootfs_is_blockdev(conf)) {
if (unshare(CLONE_NEWNS) < 0) {
- ERROR("Error unsharing mounts");
+ ERROR("Failed to unshare CLONE_NEWNS.");
goto out_fini_nonet;
}
+ INFO("Unshared CLONE_NEWNS.");
+
remount_all_slave();
if (do_rootfs_setup(conf, name, lxcpath) < 0) {
- ERROR("Error setting up rootfs mount as root before spawn");
+ ERROR("Error setting up rootfs mount as root before spawn.");
goto out_fini_nonet;
}
- INFO("Set up container rootfs as host root");
+ INFO("Set up container rootfs as host root.");
}
}
err = lxc_spawn(handler);
if (err) {
- ERROR("failed to spawn '%s'", name);
+ ERROR("Failed to spawn container \"%s\".", name);
goto out_detach_blockdev;
}
handler->conf->reboot = 0;
- netnsfd = get_netns_fd(handler->pid);
-
err = lxc_poll(name, handler);
if (err) {
- ERROR("mainloop exited with an error");
- if (netnsfd >= 0)
- close(netnsfd);
+ ERROR("LXC mainloop exited with error: %d.", err);
+ if (handler->netnsfd >= 0) {
+ close(handler->netnsfd);
+ handler->netnsfd = -1;
+ }
goto out_abort;
}
while (waitpid(handler->pid, &status, 0) < 0 && errno == EINTR)
continue;
- /*
- * If the child process exited but was not signaled,
- * it didn't call reboot. This should mean it was an
- * lxc-execute which simply exited. In any case, treat
- * it as a 'halt'
+ /* If the child process exited but was not signaled, it didn't call
+ * reboot. This should mean it was an lxc-execute which simply exited.
+ * In any case, treat it as a 'halt'.
*/
if (WIFSIGNALED(status)) {
switch(WTERMSIG(status)) {
case SIGINT: /* halt */
- DEBUG("Container halting");
+ DEBUG("Container \"%s\" is halting.", name);
break;
case SIGHUP: /* reboot */
- DEBUG("Container rebooting");
+ DEBUG("Container \"%s\" is rebooting.", name);
handler->conf->reboot = 1;
break;
case SIGSYS: /* seccomp */
- DEBUG("Container violated its seccomp policy");
+ DEBUG("Container \"%s\" violated its seccomp policy.", name);
break;
default:
- DEBUG("unknown exit status for init: %d", WTERMSIG(status));
+ DEBUG("Unknown exit status for container \"%s\" init %d.", name, WTERMSIG(status));
break;
}
}
DEBUG("Pushing physical nics back to host namespace");
- lxc_rename_phys_nics_on_shutdown(netnsfd, handler->conf);
-
- DEBUG("Tearing down virtual network devices used by container");
- lxc_delete_network(handler);
+ lxc_restore_phys_nics_to_netns(handler->netnsfd, handler->conf);
- if (netnsfd >= 0)
- close(netnsfd);
+ DEBUG("Tearing down virtual network devices used by container \"%s\".", name);
+ removed_all_netdevs = lxc_delete_network(handler);
if (handler->pinfd >= 0) {
close(handler->pinfd);
lxc_monitor_send_exit_code(name, status, handler->lxcpath);
err = lxc_error_set_and_log(handler->pid, status);
out_fini:
- lxc_delete_network(handler);
+ if (!removed_all_netdevs) {
+ DEBUG("Failed tearing down network devices used by container. Trying again!");
+ removed_all_netdevs = lxc_delete_network(handler);
+ if (!removed_all_netdevs)
+ DEBUG("Failed tearing down network devices used by container. Not trying again!");
+ }
out_detach_blockdev:
detach_block_device(handler->conf);
{
struct start_args *arg = data;
- NOTICE("exec'ing '%s'", arg->argv[0]);
+ NOTICE("Exec'ing \"%s\".", arg->argv[0]);
execvp(arg->argv[0], arg->argv);
- SYSERROR("failed to exec %s", arg->argv[0]);
+ SYSERROR("Failed to exec \"%s\".", arg->argv[0]);
return 0;
}
{
struct start_args *arg = data;
- NOTICE("'%s' started with pid '%d'", arg->argv[0], handler->pid);
+ NOTICE("Started \"%s\" with pid \"%d\".", arg->argv[0], handler->pid);
return 0;
}
.post_start = post_start
};
-int lxc_start(const char *name, char *const argv[], struct lxc_conf *conf,
+int lxc_start(const char *name, char *const argv[], struct lxc_handler *handler,
const char *lxcpath, bool backgrounded)
{
struct start_args start_arg = {
.argv = argv,
};
- conf->need_utmp_watch = 1;
- return __lxc_start(name, conf, &start_ops, &start_arg, lxcpath, backgrounded);
+ handler->conf->need_utmp_watch = 1;
+ return __lxc_start(name, handler, &start_ops, &start_arg, lxcpath, backgrounded);
}
static void lxc_destroy_container_on_signal(struct lxc_handler *handler,
if (handler->conf->rootfs.path && handler->conf->rootfs.mount) {
bret = do_destroy_container(handler->conf);
if (!bret) {
- ERROR("Error destroying rootfs for %s", name);
+ ERROR("Error destroying rootfs for container \"%s\".", name);
return;
}
}
- INFO("Destroyed rootfs for %s", name);
+ INFO("Destroyed rootfs for container \"%s\".", name);
ret = snprintf(destroy, MAXPATHLEN, "%s/%s", handler->lxcpath, name);
if (ret < 0 || ret >= MAXPATHLEN) {
- ERROR("Error printing path for %s", name);
- ERROR("Error destroying directory for %s", name);
+ ERROR("Error destroying directory for container \"%s\".", name);
return;
}
c = lxc_container_new(name, handler->lxcpath);
if (c) {
if (container_disk_lock(c)) {
- INFO("Could not update lxc_snapshots file");
+ INFO("Could not update lxc_snapshots file.");
lxc_container_put(c);
} else {
mod_all_rdeps(c, false);
}
if (am_unpriv())
- ret = userns_exec_1(handler->conf, lxc_rmdir_onedev_wrapper, destroy);
+ ret = userns_exec_1(handler->conf, lxc_rmdir_onedev_wrapper,
+ destroy, "lxc_rmdir_onedev_wrapper");
else
ret = lxc_rmdir_onedev(destroy, NULL);
if (ret < 0) {
- ERROR("Error destroying directory for %s", name);
+ ERROR("Error destroying directory for container \"%s\".", name);
return;
}
- INFO("Destroyed directory for %s", name);
+ INFO("Destroyed directory for container \"%s\".", name);
}
static int lxc_rmdir_onedev_wrapper(void *data)
static bool do_destroy_container(struct lxc_conf *conf) {
if (am_unpriv()) {
- if (userns_exec_1(conf, bdev_destroy_wrapper, conf) < 0)
+ if (userns_exec_1(conf, bdev_destroy_wrapper, conf,
+ "bdev_destroy_wrapper") < 0)
return false;
return true;
}
projects / mirror_lxc.git / blobdiff