#include "missing.h"
#include "execute.h"
#include "loopback-setup.h"
+#include "mkdir.h"
+#include "dev-setup.h"
+#include "def.h"
typedef enum MountMode {
/* This is ordered by priority! */
READONLY,
PRIVATE_TMP,
PRIVATE_VAR_TMP,
+ PRIVATE_DEV,
READWRITE
} MountMode;
(*p)->ignore = false;
- if ((mode == INACCESSIBLE || mode == READONLY) && (*i)[0] == '-') {
+ if ((mode == INACCESSIBLE || mode == READONLY || mode == READWRITE) && (*i)[0] == '-') {
(*p)->ignore = true;
(*i)++;
}
*n = t - m;
}
+static int mount_dev(BindMount *m) {
+ static const char devnodes[] =
+ "/dev/null\0"
+ "/dev/zero\0"
+ "/dev/full\0"
+ "/dev/random\0"
+ "/dev/urandom\0"
+ "/dev/tty\0";
+
+ char temporary_mount[] = "/tmp/namespace-dev-XXXXXX";
+ const char *d, *dev = NULL, *devpts = NULL, *devshm = NULL, *devkdbus = NULL, *devhugepages = NULL, *devmqueue = NULL;
+ _cleanup_umask_ mode_t u;
+ int r;
+
+ assert(m);
+
+ u = umask(0000);
+
+ if (!mkdtemp(temporary_mount))
+ return -errno;
+
+ dev = strappenda(temporary_mount, "/dev");
+ mkdir(dev, 0755);
+ if (mount("tmpfs", dev, "tmpfs", MS_NOSUID|MS_STRICTATIME, "mode=755") < 0) {
+ r = -errno;
+ goto fail;
+ }
+
+ devpts = strappenda(temporary_mount, "/dev/pts");
+ mkdir(devpts, 0755);
+ if (mount("/dev/pts", devpts, NULL, MS_BIND, NULL) < 0) {
+ r = -errno;
+ goto fail;
+ }
+
+ devshm = strappenda(temporary_mount, "/dev/shm");
+ mkdir(devshm, 01777);
+ r = mount("/dev/shm", devshm, NULL, MS_BIND, NULL);
+ if (r < 0) {
+ r = -errno;
+ goto fail;
+ }
+
+ devmqueue = strappenda(temporary_mount, "/dev/mqueue");
+ mkdir(devmqueue, 0755);
+ mount("/dev/mqueue", devmqueue, NULL, MS_BIND, NULL);
+
+ devkdbus = strappenda(temporary_mount, "/dev/kdbus");
+ mkdir(devkdbus, 0755);
+ mount("/dev/kdbus", devkdbus, NULL, MS_BIND, NULL);
+
+ devhugepages = strappenda(temporary_mount, "/dev/hugepages");
+ mkdir(devhugepages, 0755);
+ mount("/dev/hugepages", devhugepages, NULL, MS_BIND, NULL);
+
+ NULSTR_FOREACH(d, devnodes) {
+ _cleanup_free_ char *dn = NULL;
+ struct stat st;
+
+ r = stat(d, &st);
+ if (r < 0) {
+
+ if (errno == ENOENT)
+ continue;
+
+ r = -errno;
+ goto fail;
+ }
+
+ if (!S_ISBLK(st.st_mode) &&
+ !S_ISCHR(st.st_mode)) {
+ r = -EINVAL;
+ goto fail;
+ }
+
+ if (st.st_rdev == 0)
+ continue;
+
+ dn = strappend(temporary_mount, d);
+ if (!dn) {
+ r = -ENOMEM;
+ goto fail;
+ }
+
+ r = mknod(dn, st.st_mode, st.st_rdev);
+ if (r < 0) {
+ r = -errno;
+ goto fail;
+ }
+ }
+
+ dev_setup(temporary_mount);
+
+ if (mount(dev, "/dev/", NULL, MS_MOVE, NULL) < 0) {
+ r = -errno;
+ goto fail;
+ }
+
+ rmdir(dev);
+ rmdir(temporary_mount);
+
+ return 0;
+
+fail:
+ if (devpts)
+ umount(devpts);
+
+ if (devshm)
+ umount(devshm);
+
+ if (devkdbus)
+ umount(devkdbus);
+
+ if (devhugepages)
+ umount(devhugepages);
+
+ if (devmqueue)
+ umount(devmqueue);
+
+ if (dev) {
+ umount(dev);
+ rmdir(dev);
+ }
+
+ rmdir(temporary_mount);
+
+ return r;
+}
+
static int apply_mount(
BindMount *m,
const char *tmp_dir,
switch (m->mode) {
+ case PRIVATE_DEV:
+ return mount_dev(m);
+
case INACCESSIBLE:
what = "/run/systemd/inaccessible";
break;
char** inaccessible_dirs,
char* tmp_dir,
char* var_tmp_dir,
+ bool private_dev,
unsigned mount_flags) {
BindMount *m, *mounts = NULL;
n = !!tmp_dir + !!var_tmp_dir +
strv_length(read_write_dirs) +
strv_length(read_only_dirs) +
- strv_length(inaccessible_dirs);
+ strv_length(inaccessible_dirs) +
+ private_dev;
if (n > 0) {
m = mounts = (BindMount *) alloca(n * sizeof(BindMount));
m++;
}
+ if (private_dev) {
+ m->path = "/dev";
+ m->mode = PRIVATE_DEV;
+ m++;
+ }
+
assert(mounts + n == m);
qsort(mounts, n, sizeof(BindMount), mount_path_compare);
drop_duplicates(mounts, &n);
}
- /* 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 (n > 0) {
+ /* 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;
- for (m = mounts; m < mounts + n; ++m) {
- r = apply_mount(m, tmp_dir, var_tmp_dir);
- if (r < 0)
- goto fail;
- }
+ for (m = mounts; m < mounts + n; ++m) {
+ r = apply_mount(m, tmp_dir, var_tmp_dir);
+ if (r < 0)
+ goto fail;
+ }
- for (m = mounts; m < mounts + n; ++m) {
- r = make_read_only(m);
- if (r < 0)
- goto fail;
+ for (m = mounts; m < mounts + n; ++m) {
+ r = make_read_only(m);
+ if (r < 0)
+ goto fail;
+ }
}
- /* Remount / as the desired mode */
+ /* 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;
return 0;
fail:
- for (m = mounts; m < mounts + n; ++m)
- if (m->done)
- umount2(m->path, MNT_DETACH);
+ if (n > 0) {
+ for (m = mounts; m < mounts + n; ++m)
+ if (m->done)
+ umount2(m->path, MNT_DETACH);
+ }
return r;
}