diff options
Diffstat (limited to 'src/core')
| -rw-r--r-- | src/core/execute.c | 8 | ||||
| -rw-r--r-- | src/core/namespace.c | 80 | ||||
| -rw-r--r-- | src/core/namespace.h | 3 |
3 files changed, 78 insertions, 13 deletions
diff --git a/src/core/execute.c b/src/core/execute.c index 0cca4813a8..97498b23d7 100644 --- a/src/core/execute.c +++ b/src/core/execute.c @@ -1307,6 +1307,7 @@ static int exec_child( uid_t uid = UID_INVALID; gid_t gid = GID_INVALID; int i, r; + bool needs_mount_namespace; assert(unit); assert(command); @@ -1585,7 +1586,9 @@ static int exec_child( } } - if (exec_needs_mount_namespace(context, params, runtime)) { + needs_mount_namespace = exec_needs_mount_namespace(context, params, runtime); + + if (needs_mount_namespace) { char *tmp = NULL, *var = NULL; /* The runtime struct only contains the parent @@ -1602,6 +1605,7 @@ static int exec_child( } r = setup_namespace( + params->apply_chroot ? context->root_directory : NULL, context->read_write_dirs, context->read_only_dirs, context->inaccessible_dirs, @@ -1627,7 +1631,7 @@ static int exec_child( } if (params->apply_chroot) { - if (context->root_directory) + if (!needs_mount_namespace && context->root_directory) if (chroot(context->root_directory) < 0) { *exit_status = EXIT_CHROOT; return -errno; diff --git a/src/core/namespace.c b/src/core/namespace.c index bee2839f54..5b782798c8 100644 --- a/src/core/namespace.c +++ b/src/core/namespace.c @@ -36,6 +36,7 @@ #include "dev-setup.h" #include "selinux-util.h" #include "namespace.h" +#include "mkdir.h" typedef enum MountMode { /* This is ordered by priority! */ @@ -124,6 +125,22 @@ static void drop_duplicates(BindMount *m, unsigned *n) { *n = t - m; } +static int mount_move_root(const char *path) { + if (chdir(path) < 0) + return -errno; + + if (mount(path, "/", NULL, MS_MOVE, NULL) < 0) + return -errno; + + if (chroot(".") < 0) + return -errno; + + if (chdir("/") < 0) + return -errno; + + return 0; +} + static int mount_dev(BindMount *m) { static const char devnodes[] = "/dev/null\0" @@ -225,7 +242,13 @@ static int mount_dev(BindMount *m) { dev_setup(temporary_mount); - if (mount(dev, "/dev/", NULL, MS_MOVE, NULL) < 0) { + /* Create the /dev directory if missing. It is more likely to be + * missing when the service is started with RootDirectory. This is + * consistent with mount units creating the mount points when missing. + */ + (void) mkdir_p_label(m->path, 0755); + + if (mount(dev, m->path, NULL, MS_MOVE, NULL) < 0) { r = -errno; goto fail; } @@ -404,6 +427,7 @@ static int make_read_only(BindMount *m) { } int setup_namespace( + const char* root_directory, char** read_write_dirs, char** read_only_dirs, char** inaccessible_dirs, @@ -449,37 +473,56 @@ int setup_namespace( return r; if (tmp_dir) { - m->path = "/tmp"; + m->path = prefix_roota(root_directory, "/tmp"); m->mode = PRIVATE_TMP; m++; } if (var_tmp_dir) { - m->path = "/var/tmp"; + m->path = prefix_roota(root_directory, "/var/tmp"); m->mode = PRIVATE_VAR_TMP; m++; } if (private_dev) { - m->path = "/dev"; + m->path = prefix_roota(root_directory, "/dev"); m->mode = PRIVATE_DEV; m++; } if (bus_endpoint_path) { - m->path = bus_endpoint_path; + m->path = prefix_roota(root_directory, bus_endpoint_path); m->mode = PRIVATE_BUS_ENDPOINT; m++; } if (protect_home != PROTECT_HOME_NO) { - r = append_mounts(&m, STRV_MAKE("-/home", "-/run/user", "-/root"), protect_home == PROTECT_HOME_READ_ONLY ? READONLY : INACCESSIBLE); + const char *home_dir, *run_user_dir, *root_dir; + + home_dir = prefix_roota(root_directory, "/home"); + home_dir = strjoina("-", home_dir); + run_user_dir = prefix_roota(root_directory, "/run/user"); + run_user_dir = strjoina("-", run_user_dir); + root_dir = prefix_roota(root_directory, "/root"); + root_dir = strjoina("-", root_dir); + + r = append_mounts(&m, STRV_MAKE(home_dir, run_user_dir, root_dir), + protect_home == PROTECT_HOME_READ_ONLY ? READONLY : INACCESSIBLE); if (r < 0) return r; } if (protect_system != PROTECT_SYSTEM_NO) { - r = append_mounts(&m, protect_system == PROTECT_SYSTEM_FULL ? STRV_MAKE("/usr", "-/boot", "/etc") : STRV_MAKE("/usr", "-/boot"), READONLY); + const char *usr_dir, *boot_dir, *etc_dir; + + usr_dir = prefix_roota(root_directory, "/home"); + boot_dir = prefix_roota(root_directory, "/boot"); + boot_dir = strjoina("-", boot_dir); + etc_dir = prefix_roota(root_directory, "/etc"); + + r = append_mounts(&m, protect_system == PROTECT_SYSTEM_FULL + ? STRV_MAKE(usr_dir, boot_dir, etc_dir) + : STRV_MAKE(usr_dir, boot_dir), READONLY); if (r < 0) return r; } @@ -490,12 +533,20 @@ int setup_namespace( drop_duplicates(mounts, &n); } - if (n > 0) { + if (n > 0 || root_directory) { /* Remount / as SLAVE so that nothing now mounted in the namespace shows up in the parent */ if (mount(NULL, "/", NULL, MS_SLAVE|MS_REC, NULL) < 0) return -errno; + } + + if (root_directory) { + /* Turn directory into bind mount */ + if (mount(root_directory, root_directory, NULL, MS_BIND|MS_REC, NULL) < 0) + return -errno; + } + if (n > 0) { for (m = mounts; m < mounts + n; ++m) { r = apply_mount(m, tmp_dir, var_tmp_dir); if (r < 0) @@ -509,12 +560,21 @@ int setup_namespace( } } + if (root_directory) { + /* MS_MOVE does not work on MS_SHARED so the remount MS_SHARED will be done later */ + r = mount_move_root(root_directory); + + /* at this point, we cannot rollback */ + if (r < 0) + return r; + } + /* Remount / as the desired mode. Not that this will not * reestablish propagation from our side to the host, since * what's disconnected is disconnected. */ if (mount(NULL, "/", NULL, mount_flags | MS_REC, NULL) < 0) { - r = -errno; - goto fail; + /* at this point, we cannot rollback */ + return -errno; } return 0; diff --git a/src/core/namespace.h b/src/core/namespace.h index 42b92e7803..00ab22bf2e 100644 --- a/src/core/namespace.h +++ b/src/core/namespace.h @@ -41,7 +41,8 @@ typedef enum ProtectSystem { _PROTECT_SYSTEM_INVALID = -1 } ProtectSystem; -int setup_namespace(char **read_write_dirs, +int setup_namespace(const char *chroot, + char **read_write_dirs, char **read_only_dirs, char **inaccessible_dirs, const char *tmp_dir, |