X-Git-Url: https://www.chiark.greenend.org.uk/ucgi/~ianmdlvl/git?p=elogind.git;a=blobdiff_plain;f=src%2Fnspawn%2Fnspawn.c;h=a9b9a3e062f7a6d0abd78660ab5c3e22bd3996b6;hp=25828cf3ccf01e5aadd36cbb55567bb227df2911;hb=4aab5d0cbd979b2cccb88534f118bceaa86466d8;hpb=05e7da5afa07b5620c06507a3f033334a5179d21 diff --git a/src/nspawn/nspawn.c b/src/nspawn/nspawn.c index 25828cf3c..a9b9a3e06 100644 --- a/src/nspawn/nspawn.c +++ b/src/nspawn/nspawn.c @@ -187,6 +187,9 @@ static unsigned long arg_personality = 0xffffffffLU; static char *arg_image = NULL; static Volatile arg_volatile = VOLATILE_NO; static ExposePort *arg_expose_ports = NULL; +static char **arg_property = NULL; +static uid_t arg_uid_shift = UID_INVALID, arg_uid_range = 0x10000U; +static bool arg_userns = false; static void help(void) { printf("%s [OPTIONS...] [PATH] [ARGUMENTS...]\n\n" @@ -205,6 +208,7 @@ static void help(void) { " -M --machine=NAME Set the machine name for the container\n" " --uuid=UUID Set a specific machine UUID for the container\n" " -S --slice=SLICE Place the container in the specified slice\n" + " --property=NAME=VALUE Set scope unit property\n" " --private-network Disable network in container\n" " --network-interface=INTERFACE\n" " Assign an existing network interface to the\n" @@ -221,6 +225,8 @@ static void help(void) { " Add a virtual ethernet connection between host\n" " and container and add it to an existing bridge on\n" " the host\n" + " --private-users[=UIDBASE[:NUIDS]]\n" + " Run within user namespace\n" " -p --port=[PROTOCOL:]HOSTPORT[:CONTAINERPORT]\n" " Expose a container IP port on the host\n" " -Z --selinux-context=SECLABEL\n" @@ -294,6 +300,8 @@ static int parse_argv(int argc, char *argv[]) { ARG_PERSONALITY, ARG_VOLATILE, ARG_TEMPLATE, + ARG_PROPERTY, + ARG_PRIVATE_USERS, }; static const struct option options[] = { @@ -331,6 +339,8 @@ static int parse_argv(int argc, char *argv[]) { { "image", required_argument, NULL, 'i' }, { "volatile", optional_argument, NULL, ARG_VOLATILE }, { "port", required_argument, NULL, 'p' }, + { "property", required_argument, NULL, ARG_PROPERTY }, + { "private-users", optional_argument, NULL, ARG_PRIVATE_USERS }, {} }; @@ -731,6 +741,41 @@ static int parse_argv(int argc, char *argv[]) { break; } + case ARG_PROPERTY: + if (strv_extend(&arg_property, optarg) < 0) + return log_oom(); + + break; + + case ARG_PRIVATE_USERS: + if (optarg) { + _cleanup_free_ char *buffer = NULL; + const char *range, *shift; + + range = strchr(optarg, ':'); + if (range) { + buffer = strndup(optarg, range - optarg); + if (!buffer) + return log_oom(); + shift = buffer; + + range++; + if (safe_atou32(range, &arg_uid_range) < 0 || arg_uid_range <= 0) { + log_error("Failed to parse UID range: %s", range); + return -EINVAL; + } + } else + shift = optarg; + + if (parse_uid(shift, &arg_uid_shift) < 0) { + log_error("Failed to parse UID: %s", optarg); + return -EINVAL; + } + } + + arg_userns = true; + break; + case '?': return -EINVAL; @@ -816,6 +861,7 @@ static int mount_all(const char *dest) { { "devpts", "/dev/pts", "devpts","newinstance,ptmxmode=0666,mode=620,gid=" STRINGIFY(TTY_GID), MS_NOSUID|MS_NOEXEC, true }, { "tmpfs", "/dev/shm", "tmpfs", "mode=1777", MS_NOSUID|MS_NODEV|MS_STRICTATIME, true }, { "tmpfs", "/run", "tmpfs", "mode=755", MS_NOSUID|MS_NODEV|MS_STRICTATIME, true }, + { "tmpfs", "/tmp", "tmpfs", "mode=1777", MS_STRICTATIME, true }, #ifdef HAVE_SELINUX { "/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 */ @@ -826,10 +872,7 @@ static int mount_all(const char *dest) { int r = 0; for (k = 0; k < ELEMENTSOF(mount_table); k++) { - _cleanup_free_ char *where = NULL; -#ifdef HAVE_SELINUX - _cleanup_free_ char *options = NULL; -#endif + _cleanup_free_ char *where = NULL, *options = NULL; const char *o; int t; @@ -876,6 +919,19 @@ static int mount_all(const char *dest) { #endif o = mount_table[k].options; + if (arg_userns && arg_uid_shift != UID_INVALID && streq_ptr(mount_table[k].type, "tmpfs")) { + char *uid_options = NULL; + + if (o) + asprintf(&uid_options, "%s,uid=" UID_FMT ",gid=" UID_FMT, o, arg_uid_shift, arg_uid_shift); + else + asprintf(&uid_options, "uid=" UID_FMT ",gid=" UID_FMT, arg_uid_shift, arg_uid_shift); + if (!uid_options) + return log_oom(); + + free(options); + o = options = uid_options; + } if (mount(mount_table[k].what, where, @@ -961,7 +1017,7 @@ static int mount_cgroup_hierarchy(const char *dest, const char *controller, cons char *to; int r; - to = strappenda(dest, "/sys/fs/cgroup/", hierarchy); + to = strjoina(dest, "/sys/fs/cgroup/", hierarchy); r = path_is_mount_point(to, false); if (r < 0) @@ -971,9 +1027,17 @@ static int mount_cgroup_hierarchy(const char *dest, const char *controller, cons mkdir_p(to, 0755); - if (mount("cgroup", to, "cgroup", MS_NOSUID|MS_NOEXEC|MS_NODEV|(read_only ? MS_RDONLY : 0), controller) < 0) + /* The superblock mount options of the mount point need to be + * identical to the hosts', and hence writable... */ + if (mount("cgroup", to, "cgroup", MS_NOSUID|MS_NOEXEC|MS_NODEV, controller) < 0) return log_error_errno(errno, "Failed to mount to %s: %m", to); + /* ... hence let's only make the bind mount read-only, not the + * superblock. */ + if (read_only) { + if (mount(NULL, to, NULL, MS_BIND|MS_REMOUNT|MS_NOSUID|MS_NOEXEC|MS_NODEV|MS_RDONLY, NULL) < 0) + return log_error_errno(errno, "Failed to remount %s read-only: %m", to); + } return 1; } @@ -995,7 +1059,7 @@ static int mount_cgroup(const char *dest) { if (r < 0) return log_error_errno(r, "Failed to determine our own cgroup path: %m"); - cgroup_root = strappenda(dest, "/sys/fs/cgroup"); + cgroup_root = strjoina(dest, "/sys/fs/cgroup"); if (mount("tmpfs", cgroup_root, "tmpfs", MS_NOSUID|MS_NOEXEC|MS_NODEV|MS_STRICTATIME, "mode=755") < 0) return log_error_errno(errno, "Failed to mount tmpfs to /sys/fs/cgroup: %m"); @@ -1043,17 +1107,17 @@ static int mount_cgroup(const char *dest) { } } - r = mount_cgroup_hierarchy(dest, "name=systemd", "systemd", false); + r = mount_cgroup_hierarchy(dest, "name=systemd,xattr", "systemd", false); if (r < 0) return r; /* Make our own cgroup a (writable) bind mount */ - systemd_own = strappenda(dest, "/sys/fs/cgroup/systemd", own_cgroup_path); + systemd_own = strjoina(dest, "/sys/fs/cgroup/systemd", own_cgroup_path); if (mount(systemd_own, systemd_own, NULL, MS_BIND, NULL) < 0) return log_error_errno(errno, "Failed to turn %s into a bind mount: %m", own_cgroup_path); /* And then remount the systemd cgroup root read-only */ - systemd_root = strappenda(dest, "/sys/fs/cgroup/systemd"); + systemd_root = strjoina(dest, "/sys/fs/cgroup/systemd"); if (mount(NULL, systemd_root, NULL, MS_BIND|MS_REMOUNT|MS_NOSUID|MS_NOEXEC|MS_NODEV|MS_RDONLY, NULL) < 0) return log_error_errno(errno, "Failed to mount cgroup root read-only: %m"); @@ -1206,7 +1270,7 @@ static int setup_volatile_state(const char *directory) { if (r < 0) return log_error_errno(r, "Failed to remount %s read-only: %m", directory); - p = strappenda(directory, "/var"); + p = strjoina(directory, "/var"); r = mkdir(p, 0755); if (r < 0 && errno != EEXIST) return log_error_errno(errno, "Failed to create %s: %m", directory); @@ -1242,8 +1306,8 @@ static int setup_volatile(const char *directory) { tmpfs_mounted = true; - f = strappenda(directory, "/usr"); - t = strappenda(template, "/usr"); + f = strjoina(directory, "/usr"); + t = strjoina(template, "/usr"); r = mkdir(t, 0755); if (r < 0 && errno != EEXIST) { @@ -1380,6 +1444,10 @@ static int copy_devnodes(const char *dest) { if (mknod(to, st.st_mode, st.st_rdev) < 0) return log_error_errno(errno, "mknod(%s) failed: %m", to); + + if (arg_userns && arg_uid_shift != UID_INVALID) + if (lchown(to, arg_uid_shift, arg_uid_shift) < 0) + return log_error_errno(errno, "chown() of device node %s failed: %m", to); } } @@ -1396,6 +1464,10 @@ static int setup_ptmx(const char *dest) { if (symlink("pts/ptmx", p) < 0) return log_error_errno(errno, "Failed to create /dev/ptmx symlink: %m"); + if (arg_userns && arg_uid_shift != UID_INVALID) + if (lchown(p, arg_uid_shift, arg_uid_shift) < 0) + return log_error_errno(errno, "lchown() of symlink %s failed: %m", p); + return 0; } @@ -1425,7 +1497,7 @@ static int setup_dev_console(const char *dest, const char *console) { * /dev/console. (Note that the major minor doesn't actually * matter here, since we mount it over anyway). */ - to = strappenda(dest, "/dev/console"); + to = strjoina(dest, "/dev/console"); if (mknod(to, (st.st_mode & ~07777) | 0600, st.st_rdev) < 0) return log_error_errno(errno, "mknod() for /dev/console failed: %m"); @@ -1888,6 +1960,7 @@ static int register_machine(pid_t pid, int local_ifindex) { local_ifindex > 0 ? 1 : 0, local_ifindex); } else { _cleanup_bus_message_unref_ sd_bus_message *m = NULL; + char **i; r = sd_bus_message_new_method_call( bus, @@ -1897,7 +1970,7 @@ static int register_machine(pid_t pid, int local_ifindex) { "org.freedesktop.machine1.Manager", "CreateMachineWithNetwork"); if (r < 0) - return log_error_errno(r, "Failed to create message: %m"); + return bus_log_create_error(r); r = sd_bus_message_append( m, @@ -1910,21 +1983,21 @@ static int register_machine(pid_t pid, int local_ifindex) { strempty(arg_directory), local_ifindex > 0 ? 1 : 0, local_ifindex); if (r < 0) - return log_error_errno(r, "Failed to append message arguments: %m"); + return bus_log_create_error(r); r = sd_bus_message_open_container(m, 'a', "(sv)"); if (r < 0) - return log_error_errno(r, "Failed to open container: %m"); + return bus_log_create_error(r); if (!isempty(arg_slice)) { r = sd_bus_message_append(m, "(sv)", "Slice", "s", arg_slice); if (r < 0) - return log_error_errno(r, "Failed to append slice: %m"); + return bus_log_create_error(r); } r = sd_bus_message_append(m, "(sv)", "DevicePolicy", "s", "strict"); if (r < 0) - return log_error_errno(r, "Failed to add device policy: %m"); + return bus_log_create_error(r); r = sd_bus_message_append(m, "(sv)", "DeviceAllow", "a(ss)", 9, /* Allow the container to @@ -1950,9 +2023,23 @@ static int register_machine(pid_t pid, int local_ifindex) { if (r < 0) return log_error_errno(r, "Failed to add device whitelist: %m"); + STRV_FOREACH(i, arg_property) { + r = sd_bus_message_open_container(m, 'r', "sv"); + if (r < 0) + return bus_log_create_error(r); + + r = bus_append_unit_property_assignment(m, *i); + if (r < 0) + return r; + + r = sd_bus_message_close_container(m); + if (r < 0) + return bus_log_create_error(r); + } + r = sd_bus_message_close_container(m); if (r < 0) - return log_error_errno(r, "Failed to close container: %m"); + return bus_log_create_error(r); r = sd_bus_call(bus, m, 0, &error, NULL); } @@ -2476,15 +2563,18 @@ static int setup_seccomp(void) { static const int blacklist[] = { SCMP_SYS(kexec_load), SCMP_SYS(open_by_handle_at), - SCMP_SYS(init_module), - SCMP_SYS(finit_module), - SCMP_SYS(delete_module), SCMP_SYS(iopl), SCMP_SYS(ioperm), SCMP_SYS(swapon), SCMP_SYS(swapoff), }; + static const int kmod_blacklist[] = { + SCMP_SYS(init_module), + SCMP_SYS(finit_module), + SCMP_SYS(delete_module), + }; + scmp_filter_ctx seccomp; unsigned i; int r; @@ -2509,6 +2599,20 @@ static int setup_seccomp(void) { } } + /* If the CAP_SYS_MODULE capability is not requested then + * we'll block the kmod syscalls too */ + if (!(arg_retain & (1ULL << CAP_SYS_MODULE))) { + for (i = 0; i < ELEMENTSOF(kmod_blacklist); i++) { + r = seccomp_rule_add(seccomp, SCMP_ACT_ERRNO(EPERM), kmod_blacklist[i], 0); + if (r == -EFAULT) + continue; /* unknown syscall */ + if (r < 0) { + log_error_errno(r, "Failed to block syscall: %m"); + goto finish; + } + } + } + /* Audit is broken in containers, much of the userspace audit hookup will fail if running inside a container. We don't @@ -2555,10 +2659,10 @@ static int setup_propagate(const char *root) { (void) mkdir_p("/run/systemd/nspawn/", 0755); (void) mkdir_p("/run/systemd/nspawn/propagate", 0600); - p = strappenda("/run/systemd/nspawn/propagate/", arg_machine); + p = strjoina("/run/systemd/nspawn/propagate/", arg_machine); (void) mkdir_p(p, 0600); - q = strappenda(root, "/run/systemd/nspawn/incoming"); + q = strjoina(root, "/run/systemd/nspawn/incoming"); mkdir_parents(q, 0755); mkdir_p(q, 0600); @@ -2650,7 +2754,7 @@ static int setup_image(char **device_path, int *loop_nr) { #define PARTITION_TABLE_BLURB \ "Note that the disk image needs to either contain only a single MBR partition of\n" \ - "type 0x83 that is marked bootable, or a sinlge GPT partition of type" \ + "type 0x83 that is marked bootable, or a single GPT partition of type " \ "0FC63DAF-8483-4772-8E79-3D69D8477DE4 or follow\n" \ " http://www.freedesktop.org/wiki/Specifications/DiscoverablePartitionsSpec/\n" \ "to be bootable with systemd-nspawn." @@ -3041,7 +3145,7 @@ static int mount_device(const char *what, const char *where, const char *directo rw = false; if (directory) - p = strappenda(where, directory); + p = strjoina(where, directory); else p = where; @@ -3541,6 +3645,38 @@ static int determine_names(void) { return 0; } +static int determine_uid_shift(void) { + int r; + + if (!arg_userns) + return 0; + + if (arg_uid_shift == UID_INVALID) { + struct stat st; + + r = stat(arg_directory, &st); + if (r < 0) + return log_error_errno(errno, "Failed to determine UID base of %s: %m", arg_directory); + + arg_uid_shift = st.st_uid & UINT32_C(0xffff0000); + + if (arg_uid_shift != (st.st_gid & UINT32_C(0xffff0000))) { + log_error("UID and GID base of %s don't match.", arg_directory); + return -EINVAL; + } + + arg_uid_range = UINT32_C(0x10000); + } + + if (arg_uid_shift > (uid_t) -1 - arg_uid_range) { + log_error("UID base too high for UID range."); + return -EINVAL; + } + + log_info("Using user namespaces with base " UID_FMT " and range " UID_FMT ".", arg_uid_shift, arg_uid_range); + return 0; +} + int main(int argc, char *argv[]) { _cleanup_free_ char *device_path = NULL, *root_device = NULL, *home_device = NULL, *srv_device = NULL, *console = NULL; @@ -3555,6 +3691,7 @@ int main(int argc, char *argv[]) { int ret = EXIT_SUCCESS; union in_addr_union exposed = {}; _cleanup_release_lock_file_ LockFile tree_global_lock = LOCK_FILE_INIT, tree_local_lock = LOCK_FILE_INIT; + bool interactive; log_parse_environment(); log_open(); @@ -3601,7 +3738,6 @@ int main(int argc, char *argv[]) { } if (arg_ephemeral) { - _cleanup_release_lock_file_ LockFile original_lock = LOCK_FILE_INIT; char *np; /* If the specified path is a mount point we @@ -3677,7 +3813,7 @@ int main(int argc, char *argv[]) { } else { const char *p; - p = strappenda(arg_directory, + p = strjoina(arg_directory, argc > optind && path_is_absolute(argv[optind]) ? argv[optind] : "/usr/bin/"); if (access(p, F_OK) < 0) { log_error("Directory %s lacks the binary to execute or doesn't look like a binary tree. Refusing.", arg_directory); @@ -3729,6 +3865,12 @@ int main(int argc, char *argv[]) { goto finish; } + r = determine_uid_shift(); + if (r < 0) + goto finish; + + interactive = isatty(STDIN_FILENO) > 0 && isatty(STDOUT_FILENO) > 0; + master = posix_openpt(O_RDWR|O_NOCTTY|O_CLOEXEC|O_NDELAY); if (master < 0) { r = log_error_errno(errno, "Failed to acquire pseudo tty: %m"); @@ -3741,15 +3883,15 @@ int main(int argc, char *argv[]) { goto finish; } - if (!arg_quiet) - log_info("Spawning container %s on %s.\nPress ^] three times within 1s to kill container.", - arg_machine, arg_image ?: arg_directory); - if (unlockpt(master) < 0) { r = log_error_errno(errno, "Failed to unlock tty: %m"); goto finish; } + if (!arg_quiet) + log_info("Spawning container %s on %s.\nPress ^] three times within 1s to kill container.", + arg_machine, arg_image ?: arg_directory); + assert_se(sigemptyset(&mask) == 0); sigset_add_many(&mask, SIGCHLD, SIGWINCH, SIGTERM, SIGINT, -1); assert_se(sigprocmask(SIG_BLOCK, &mask, NULL) == 0); @@ -3835,31 +3977,33 @@ int main(int argc, char *argv[]) { master = safe_close(master); - close_nointr(STDIN_FILENO); - close_nointr(STDOUT_FILENO); - close_nointr(STDERR_FILENO); - kmsg_socket_pair[0] = safe_close(kmsg_socket_pair[0]); rtnl_socket_pair[0] = safe_close(rtnl_socket_pair[0]); reset_all_signal_handlers(); reset_signal_mask(); - r = open_terminal(console, O_RDWR); - if (r != STDIN_FILENO) { - if (r >= 0) { - safe_close(r); - r = -EINVAL; - } + if (interactive) { + close_nointr(STDIN_FILENO); + close_nointr(STDOUT_FILENO); + close_nointr(STDERR_FILENO); - log_error_errno(r, "Failed to open console: %m"); - _exit(EXIT_FAILURE); - } + r = open_terminal(console, O_RDWR); + if (r != STDIN_FILENO) { + if (r >= 0) { + safe_close(r); + r = -EINVAL; + } - if (dup2(STDIN_FILENO, STDOUT_FILENO) != STDOUT_FILENO || - dup2(STDIN_FILENO, STDERR_FILENO) != STDERR_FILENO) { - log_error_errno(errno, "Failed to duplicate console: %m"); - _exit(EXIT_FAILURE); + log_error_errno(r, "Failed to open console: %m"); + _exit(EXIT_FAILURE); + } + + if (dup2(STDIN_FILENO, STDOUT_FILENO) != STDOUT_FILENO || + dup2(STDIN_FILENO, STDERR_FILENO) != STDERR_FILENO) { + log_error_errno(errno, "Failed to duplicate console: %m"); + _exit(EXIT_FAILURE); + } } if (setsid() < 0) { @@ -3875,6 +4019,9 @@ int main(int argc, char *argv[]) { _exit(EXIT_FAILURE); } + if (arg_private_network) + loopback_setup(); + /* Mark everything as slave, so that we still * receive mounts from the real root, but don't * propagate mounts to the real root. */ @@ -3945,7 +4092,7 @@ int main(int argc, char *argv[]) { /* Tell the parent that we are ready, and that * it can cgroupify us to that we lack access * to certain devices and resources. */ - (void) barrier_place(&barrier); + (void) barrier_place(&barrier); /* #1 */ if (setup_boot_id(arg_directory) < 0) _exit(EXIT_FAILURE); @@ -3970,7 +4117,7 @@ int main(int argc, char *argv[]) { /* Wait until we are cgroup-ified, so that we * can mount the right cgroup path writable */ - (void) barrier_sync_next(&barrier); + (void) barrier_place_and_sync(&barrier); /* #2 */ if (mount_cgroup(arg_directory) < 0) _exit(EXIT_FAILURE); @@ -3995,16 +4142,50 @@ int main(int argc, char *argv[]) { _exit(EXIT_FAILURE); } - umask(0022); + if (arg_userns) { + if (unshare(CLONE_NEWUSER) < 0) { + log_error_errno(errno, "unshare(CLONE_NEWUSER) failed: %m"); + _exit(EXIT_FAILURE); + } - if (arg_private_network) - loopback_setup(); + /* Tell the parent, that it now can + * write the UID map. */ + (void) barrier_place(&barrier); /* #3 */ + + /* Wait until the parent wrote the UID + * map */ + (void) barrier_place_and_sync(&barrier); /* #4 */ + } + + umask(0022); if (drop_capabilities() < 0) { log_error_errno(errno, "drop_capabilities() failed: %m"); _exit(EXIT_FAILURE); } + setup_hostname(); + + if (arg_personality != 0xffffffffLU) { + if (personality(arg_personality) < 0) { + log_error_errno(errno, "personality() failed: %m"); + _exit(EXIT_FAILURE); + } + } else if (secondary) { + if (personality(PER_LINUX32) < 0) { + log_error_errno(errno, "personality() failed: %m"); + _exit(EXIT_FAILURE); + } + } + +#ifdef HAVE_SELINUX + if (arg_selinux_context) + if (setexeccon((security_context_t) arg_selinux_context) < 0) { + log_error_errno(errno, "setexeccon(\"%s\") failed: %m", arg_selinux_context); + _exit(EXIT_FAILURE); + } +#endif + r = change_uid_gid(&home); if (r < 0) _exit(EXIT_FAILURE); @@ -4039,28 +4220,6 @@ int main(int argc, char *argv[]) { } } - setup_hostname(); - - if (arg_personality != 0xffffffffLU) { - if (personality(arg_personality) < 0) { - log_error_errno(errno, "personality() failed: %m"); - _exit(EXIT_FAILURE); - } - } else if (secondary) { - if (personality(PER_LINUX32) < 0) { - log_error_errno(errno, "personality() failed: %m"); - _exit(EXIT_FAILURE); - } - } - -#ifdef HAVE_SELINUX - if (arg_selinux_context) - if (setexeccon((security_context_t) arg_selinux_context) < 0) { - log_error_errno(errno, "setexeccon(\"%s\") failed: %m", arg_selinux_context); - _exit(EXIT_FAILURE); - } -#endif - if (!strv_isempty(arg_setenv)) { char **n; @@ -4074,9 +4233,10 @@ int main(int argc, char *argv[]) { } else env_use = (char**) envp; - /* Wait until the parent is ready with the setup, too... */ - if (!barrier_place_and_sync(&barrier)) - _exit(EXIT_FAILURE); + /* Let the parent know that we are ready and + * wait until the parent is ready with the + * setup, too... */ + (void) barrier_place_and_sync(&barrier); /* #5 */ if (arg_boot) { char **a; @@ -4115,10 +4275,12 @@ int main(int argc, char *argv[]) { kmsg_socket_pair[1] = safe_close(kmsg_socket_pair[1]); rtnl_socket_pair[1] = safe_close(rtnl_socket_pair[1]); + (void) barrier_place(&barrier); /* #1 */ + /* Wait for the most basic Child-setup to be done, * before we add hardware to it, and place it in a * cgroup. */ - if (barrier_sync_next(&barrier)) { + if (barrier_sync(&barrier)) { /* #1 */ int ifi = 0; r = move_network_interfaces(pid); @@ -4145,6 +4307,35 @@ int main(int argc, char *argv[]) { if (r < 0) goto finish; + /* Notify the child that the parent is ready with all + * its setup, and that the child can now hand over + * control to the code to run inside the container. */ + (void) barrier_place(&barrier); /* #2 */ + + if (arg_userns) { + char uid_map[strlen("/proc//uid_map") + DECIMAL_STR_MAX(uid_t) + 1], line[DECIMAL_STR_MAX(uid_t)*3+3+1]; + + (void) barrier_place_and_sync(&barrier); /* #3 */ + + xsprintf(uid_map, "/proc/" PID_FMT "/uid_map", pid); + xsprintf(line, UID_FMT " " UID_FMT " " UID_FMT "\n", 0, arg_uid_shift, arg_uid_range); + r = write_string_file(uid_map, line); + if (r < 0) { + log_error_errno(r, "Failed to write UID map: %m"); + goto finish; + } + + /* We always assign the same UID and GID ranges */ + xsprintf(uid_map, "/proc/" PID_FMT "/gid_map", pid); + r = write_string_file(uid_map, line); + if (r < 0) { + log_error_errno(r, "Failed to write GID map: %m"); + goto finish; + } + + (void) barrier_place(&barrier); /* #4 */ + } + /* Block SIGCHLD here, before notifying child. * process_pty() will handle it with the other signals. */ r = sigprocmask(SIG_BLOCK, &mask_chld, NULL); @@ -4156,13 +4347,8 @@ int main(int argc, char *argv[]) { if (r < 0) goto finish; - /* Notify the child that the parent is ready with all - * its setup, and that the child can now hand over - * control to the code to run inside the container. */ - (void) barrier_place(&barrier); - - /* And wait that the child is completely ready now. */ - if (barrier_place_and_sync(&barrier)) { + /* Let the child know that we are ready and wait that the child is completely ready now. */ + if (barrier_place_and_sync(&barrier)) { /* #5 */ _cleanup_event_unref_ sd_event *event = NULL; _cleanup_(pty_forward_freep) PTYForward *forward = NULL; _cleanup_rtnl_unref_ sd_rtnl *rtnl = NULL; @@ -4202,7 +4388,7 @@ int main(int argc, char *argv[]) { rtnl_socket_pair[0] = safe_close(rtnl_socket_pair[0]); - r = pty_forward_new(event, master, true, &forward); + r = pty_forward_new(event, master, true, !interactive, &forward); if (r < 0) { log_error_errno(r, "Failed to create PTY forwarder: %m"); goto finish; @@ -4286,7 +4472,7 @@ finish: if (arg_machine) { const char *p; - p = strappenda("/run/systemd/nspawn/propagate/", arg_machine); + p = strjoina("/run/systemd/nspawn/propagate/", arg_machine); (void) rm_rf(p, false, true, false); }