X-Git-Url: http://www.chiark.greenend.org.uk/ucgi/~ianmdlvl/git?a=blobdiff_plain;f=src%2Fnspawn%2Fnspawn.c;h=ed72c3ebf1cffc43fae0455694abda1038f76510;hb=9c1c7f712d8270c4f6bd8141d0b1acb1f031fa08;hp=14de7f8b43b135c4a000abf1eda8ef12d00c0081;hpb=57fb9fb56db0584581ce33ee842dcbf5f1136856;p=elogind.git diff --git a/src/nspawn/nspawn.c b/src/nspawn/nspawn.c index 14de7f8b4..ed72c3ebf 100644 --- a/src/nspawn/nspawn.c +++ b/src/nspawn/nspawn.c @@ -53,6 +53,7 @@ #include "path-util.h" #include "loopback-setup.h" #include "sd-id128.h" +#include "dev-setup.h" typedef enum LinkJournal { LINK_NO, @@ -205,10 +206,8 @@ static int parse_argv(int argc, char *argv[]) { char *t; t = strndup(word, length); - if (!t) { - log_error("Out of memory."); - return -ENOMEM; - } + if (!t) + return log_oom(); if (cap_from_name(t, &cap) < 0) { log_error("Failed to parse capability %s.", t); @@ -268,16 +267,15 @@ static int mount_all(const char *dest) { static const MountPoint mount_table[] = { { "proc", "/proc", "proc", NULL, MS_NOSUID|MS_NOEXEC|MS_NODEV, true }, - { "/proc/sys", "/proc/sys", "bind", NULL, MS_BIND, true }, /* Bind mount first */ - { "/proc/sys", "/proc/sys", "bind", NULL, MS_BIND|MS_RDONLY|MS_REMOUNT, true }, /* Then, make it r/o */ - { "/sys", "/sys", "bind", NULL, MS_BIND, true }, /* Bind mount first */ - { "/sys", "/sys", "bind", NULL, MS_BIND|MS_RDONLY|MS_REMOUNT, true }, /* Then, make it r/o */ + { "/proc/sys", "/proc/sys", NULL, NULL, MS_BIND, true }, /* Bind mount first */ + { NULL, "/proc/sys", NULL, NULL, MS_BIND|MS_RDONLY|MS_REMOUNT, true }, /* Then, make it r/o */ + { "sysfs", "/sys", "sysfs", NULL, MS_RDONLY|MS_NOSUID|MS_NOEXEC|MS_NODEV, true }, { "tmpfs", "/dev", "tmpfs", "mode=755", MS_NOSUID|MS_STRICTATIME, true }, - { "/dev/pts", "/dev/pts", "bind", NULL, MS_BIND, true }, + { "/dev/pts", "/dev/pts", NULL, NULL, MS_BIND, true }, { "tmpfs", "/run", "tmpfs", "mode=755", MS_NOSUID|MS_NODEV|MS_STRICTATIME, true }, #ifdef HAVE_SELINUX - { "/sys/fs/selinux", "/sys/fs/selinux", "bind", NULL, MS_BIND, false }, /* Bind mount first */ - { "/sys/fs/selinux", "/sys/fs/selinux", "bind", NULL, MS_BIND|MS_RDONLY|MS_REMOUNT, false }, /* Then, make it r/o */ + { "/sys/fs/selinux", "/sys/fs/selinux", NULL, NULL, MS_BIND, false }, /* Bind mount first */ + { NULL, "/sys/fs/selinux", NULL, NULL, MS_BIND|MS_RDONLY|MS_REMOUNT, false }, /* Then, make it r/o */ #endif }; @@ -289,7 +287,7 @@ static int mount_all(const char *dest) { int t; if (asprintf(&where, "%s/%s", dest, mount_table[k].where) < 0) { - log_error("Out of memory"); + log_oom(); if (r == 0) r = -ENOMEM; @@ -297,7 +295,7 @@ static int mount_all(const char *dest) { break; } - t = path_is_mount_point(where, false); + t = path_is_mount_point(where, true); if (t < 0) { log_error("Failed to detect whether %s is a mount point: %s", where, strerror(-t)); free(where); @@ -308,6 +306,10 @@ static int mount_all(const char *dest) { continue; } + /* Skip this entry if it is not a remount. */ + if (mount_table[k].what && t > 0) + continue; + mkdir_p_label(where, 0755); if (mount(mount_table[k].what, @@ -335,20 +337,16 @@ static int setup_timezone(const char *dest) { assert(dest); /* Fix the timezone, if possible */ - if (asprintf(&where, "%s/etc/localtime", dest) < 0) { - log_error("Out of memory"); - return -ENOMEM; - } + if (asprintf(&where, "%s/etc/localtime", dest) < 0) + return log_oom(); if (mount("/etc/localtime", where, "bind", MS_BIND, NULL) >= 0) mount("/etc/localtime", where, "bind", MS_BIND|MS_REMOUNT|MS_RDONLY, NULL); free(where); - if (asprintf(&where, "%s/etc/timezone", dest) < 0) { - log_error("Out of memory"); - return -ENOMEM; - } + if (asprintf(&where, "%s/etc/timezone", dest) < 0) + return log_oom(); if (mount("/etc/timezone", where, "bind", MS_BIND, NULL) >= 0) mount("/etc/timezone", where, "bind", MS_BIND|MS_REMOUNT|MS_RDONLY, NULL); @@ -368,8 +366,7 @@ static int setup_resolv_conf(const char *dest) { /* Fix resolv.conf, if possible */ if (asprintf(&where, "%s/etc/resolv.conf", dest) < 0) { - log_error("Out of memory"); - return -ENOMEM; + return log_oom(); } if (mount("/etc/resolv.conf", where, "bind", MS_BIND, NULL) >= 0) @@ -480,8 +477,7 @@ static int setup_dev_console(const char *dest, const char *console) { } if (asprintf(&to, "%s/dev/console", dest) < 0) { - log_error("Out of memory"); - r = -ENOMEM; + r = log_oom(); goto finish; } @@ -535,14 +531,12 @@ static int setup_kmsg(const char *dest, int kmsg_socket) { * avoid any problems with containers deadlocking due to this * we simply make /dev/kmsg unavailable to the container. */ if (asprintf(&from, "%s/dev/kmsg", dest) < 0) { - log_error("Out of memory"); - r = -ENOMEM; + r = log_oom(); goto finish; } if (asprintf(&to, "%s/proc/kmsg", dest) < 0) { - log_error("Out of memory"); - r = -ENOMEM; + r = log_oom(); goto finish; } @@ -639,8 +633,7 @@ static int setup_journal(const char *directory) { p = strappend(directory, "/etc/machine-id"); if (!p) { - log_error("Out of memory"); - r = -ENOMEM; + r = log_oom(); goto finish; } @@ -670,8 +663,7 @@ static int setup_journal(const char *directory) { p = strappend("/var/log/journal/", l); q = strjoin(directory, "/var/log/journal/", l, NULL); if (!p || !q) { - log_error("Out of memory"); - r = -ENOMEM; + r = log_oom(); goto finish; } @@ -808,13 +800,15 @@ static int process_pty(int master, sigset_t *mask) { fd_nonblock(STDOUT_FILENO, 1); fd_nonblock(master, 1); - if ((signal_fd = signalfd(-1, mask, SFD_NONBLOCK|SFD_CLOEXEC)) < 0) { + signal_fd = signalfd(-1, mask, SFD_NONBLOCK|SFD_CLOEXEC); + if (signal_fd < 0) { log_error("signalfd(): %m"); r = -errno; goto finish; } - if ((ep = epoll_create1(EPOLL_CLOEXEC)) < 0) { + ep = epoll_create1(EPOLL_CLOEXEC); + if (ep < 0) { log_error("Failed to create epoll: %m"); r = -errno; goto finish; @@ -850,7 +844,8 @@ static int process_pty(int master, sigset_t *mask) { ssize_t k; int i, nfds; - if ((nfds = epoll_wait(ep, ev, ELEMENTSOF(ev), -1)) < 0) { + nfds = epoll_wait(ep, ev, ELEMENTSOF(ev), -1); + if (nfds < 0) { if (errno == EINTR || errno == EAGAIN) continue; @@ -885,7 +880,8 @@ static int process_pty(int master, sigset_t *mask) { struct signalfd_siginfo sfsi; ssize_t n; - if ((n = read(signal_fd, &sfsi, sizeof(sfsi))) != sizeof(sfsi)) { + n = read(signal_fd, &sfsi, sizeof(sfsi)); + if (n != sizeof(sfsi)) { if (n >= 0) { log_error("Failed to read from signalfd: invalid block size"); @@ -921,7 +917,8 @@ static int process_pty(int master, sigset_t *mask) { if (stdin_readable && in_buffer_full < LINE_MAX) { - if ((k = read(STDIN_FILENO, in_buffer + in_buffer_full, LINE_MAX - in_buffer_full)) < 0) { + k = read(STDIN_FILENO, in_buffer + in_buffer_full, LINE_MAX - in_buffer_full); + if (k < 0) { if (errno == EAGAIN || errno == EPIPE || errno == ECONNRESET || errno == EIO) stdin_readable = false; @@ -936,7 +933,8 @@ static int process_pty(int master, sigset_t *mask) { if (master_writable && in_buffer_full > 0) { - if ((k = write(master, in_buffer, in_buffer_full)) < 0) { + k = write(master, in_buffer, in_buffer_full); + if (k < 0) { if (errno == EAGAIN || errno == EPIPE || errno == ECONNRESET || errno == EIO) master_writable = false; @@ -955,7 +953,8 @@ static int process_pty(int master, sigset_t *mask) { if (master_readable && out_buffer_full < LINE_MAX) { - if ((k = read(master, out_buffer + out_buffer_full, LINE_MAX - out_buffer_full)) < 0) { + k = read(master, out_buffer + out_buffer_full, LINE_MAX - out_buffer_full); + if (k < 0) { if (errno == EAGAIN || errno == EPIPE || errno == ECONNRESET || errno == EIO) master_readable = false; @@ -970,7 +969,8 @@ static int process_pty(int master, sigset_t *mask) { if (stdout_writable && out_buffer_full > 0) { - if ((k = write(STDOUT_FILENO, out_buffer, out_buffer_full)) < 0) { + k = write(STDOUT_FILENO, out_buffer, out_buffer_full); + if (k < 0) { if (errno == EAGAIN || errno == EPIPE || errno == ECONNRESET || errno == EIO) stdout_writable = false; @@ -1015,7 +1015,8 @@ int main(int argc, char *argv[]) { log_parse_environment(); log_open(); - if ((r = parse_argv(argc, argv)) <= 0) + r = parse_argv(argc, argv); + if (r <= 0) goto finish; if (arg_directory) { @@ -1054,7 +1055,8 @@ int main(int argc, char *argv[]) { goto finish; } - if ((k = cg_get_by_pid(SYSTEMD_CGROUP_CONTROLLER, 0, &oldcg)) < 0) { + k = cg_get_by_pid(SYSTEMD_CGROUP_CONTROLLER, 0, &oldcg); + if (k < 0) { log_error("Failed to determine current cgroup: %s", strerror(-k)); goto finish; } @@ -1070,18 +1072,20 @@ int main(int argc, char *argv[]) { goto finish; } - STRV_FOREACH(controller,arg_controllers) { + STRV_FOREACH(controller, arg_controllers) { k = cg_create_and_attach(*controller, newcg, 0); if (k < 0) log_warning("Failed to create cgroup in controller %s: %s", *controller, strerror(-k)); } - if ((master = posix_openpt(O_RDWR|O_NOCTTY|O_CLOEXEC|O_NDELAY)) < 0) { + master = posix_openpt(O_RDWR|O_NOCTTY|O_CLOEXEC|O_NDELAY); + if (master < 0) { log_error("Failed to acquire pseudo tty: %m"); goto finish; } - if (!(console = ptsname(master))) { + console = ptsname(master); + if (!console) { log_error("Failed to determine tty name: %m"); goto finish; } @@ -1163,24 +1167,37 @@ int main(int argc, char *argv[]) { assert_se(sigemptyset(&mask) == 0); assert_se(sigprocmask(SIG_SETMASK, &mask, NULL) == 0); - if (setsid() < 0) + if (open_terminal(console, O_RDWR) != STDIN_FILENO || + dup2(STDIN_FILENO, STDOUT_FILENO) != STDOUT_FILENO || + dup2(STDIN_FILENO, STDERR_FILENO) != STDERR_FILENO) goto child_fail; - if (prctl(PR_SET_PDEATHSIG, SIGKILL) < 0) + if (setsid() < 0) { + log_error("setsid() failed: %m"); goto child_fail; + } - /* Mark / as private, in case somebody marked it shared */ - if (mount(NULL, "/", NULL, MS_PRIVATE|MS_REC, NULL) < 0) + if (prctl(PR_SET_PDEATHSIG, SIGKILL) < 0) { + log_error("PR_SET_PDEATHSIG failed: %m"); goto child_fail; + } + + /* Mark everything as slave, so that we still + * receive mounts from the real root, but don't + * propagate mounts to the real root. */ + if (mount(NULL, "/", NULL, MS_SLAVE|MS_REC, NULL) < 0) { + log_error("MS_SLAVE|MS_REC failed: %m"); + goto child_fail; + } /* Turn directory into bind mount */ - if (mount(arg_directory, arg_directory, "bind", MS_BIND, NULL) < 0) { + if (mount(arg_directory, arg_directory, "bind", MS_BIND|MS_REC, NULL) < 0) { log_error("Failed to make bind mount."); goto child_fail; } if (arg_read_only) - if (mount(arg_directory, arg_directory, "bind", MS_BIND|MS_REMOUNT|MS_RDONLY, NULL) < 0) { + if (mount(arg_directory, arg_directory, "bind", MS_BIND|MS_REMOUNT|MS_RDONLY|MS_REC, NULL) < 0) { log_error("Failed to make read-only."); goto child_fail; } @@ -1191,6 +1208,8 @@ int main(int argc, char *argv[]) { if (copy_devnodes(arg_directory) < 0) goto child_fail; + dev_setup(arg_directory); + if (setup_dev_console(arg_directory, console) < 0) goto child_fail; @@ -1213,13 +1232,8 @@ int main(int argc, char *argv[]) { goto child_fail; } - if (open_terminal("dev/console", O_RDWR) != STDIN_FILENO || - dup2(STDIN_FILENO, STDOUT_FILENO) != STDOUT_FILENO || - dup2(STDIN_FILENO, STDERR_FILENO) != STDERR_FILENO) - goto child_fail; - - if (mount(arg_directory, "/", "bind", MS_MOVE, NULL) < 0) { - log_error("mount(MS_BIND) failed: %m"); + if (mount(arg_directory, "/", NULL, MS_MOVE, NULL) < 0) { + log_error("mount(MS_MOVE) failed: %m"); goto child_fail; } @@ -1278,13 +1292,13 @@ int main(int argc, char *argv[]) { if ((asprintf((char**)(envp + 3), "HOME=%s", home ? home: "/root") < 0) || (asprintf((char**)(envp + 4), "USER=%s", arg_user ? arg_user : "root") < 0) || (asprintf((char**)(envp + 5), "LOGNAME=%s", arg_user ? arg_user : "root") < 0)) { - log_error("Out of memory"); + log_oom(); goto child_fail; } if (arg_uuid) { if (asprintf((char**)(envp + 6), "container_uuid=%s", arg_uuid) < 0) { - log_error("Out of memory"); + log_oom(); goto child_fail; } }