mount: don't mount securityfs in a container

This commit is contained in:
Lennart Poettering 2012-09-18 12:05:47 +02:00
parent 6569cae18e
commit c481f78be7
2 changed files with 21 additions and 20 deletions

4
TODO
View File

@ -86,10 +86,6 @@ Features:
* system-wide seccomp filter
* securityfs: don't mount in container
* slave/shared remount root fs in container might clash with CAP_SYS_MOUNTS
* ability to pass fds into systemd
* system.conf should have controls for cgroups

View File

@ -40,6 +40,7 @@
#include "mkdir.h"
#include "path-util.h"
#include "missing.h"
#include "virt.h"
#ifndef TTY_GID
#define TTY_GID 5
@ -52,6 +53,7 @@ typedef struct MountPoint {
const char *options;
unsigned long flags;
bool fatal;
bool in_container;
} MountPoint;
/* The first three entries we might need before SELinux is up. The
@ -60,15 +62,15 @@ typedef struct MountPoint {
#define N_EARLY_MOUNT 4
static const MountPoint mount_table[] = {
{ "proc", "/proc", "proc", NULL, MS_NOSUID|MS_NOEXEC|MS_NODEV, true },
{ "sysfs", "/sys", "sysfs", NULL, MS_NOSUID|MS_NOEXEC|MS_NODEV, true },
{ "devtmpfs", "/dev", "devtmpfs", "mode=755", MS_NOSUID|MS_STRICTATIME, true },
{ "securityfs", "/sys/kernel/security", "securityfs", NULL, MS_NOSUID|MS_NOEXEC|MS_NODEV, false },
{ "tmpfs", "/dev/shm", "tmpfs", "mode=1777", MS_NOSUID|MS_NODEV|MS_STRICTATIME, true },
{ "devpts", "/dev/pts", "devpts", "mode=620,gid=" STRINGIFY(TTY_GID), MS_NOSUID|MS_NOEXEC, false },
{ "tmpfs", "/run", "tmpfs", "mode=755", MS_NOSUID|MS_NODEV|MS_STRICTATIME, true },
{ "tmpfs", "/sys/fs/cgroup", "tmpfs", "mode=755", MS_NOSUID|MS_NOEXEC|MS_NODEV|MS_STRICTATIME, false },
{ "cgroup", "/sys/fs/cgroup/systemd", "cgroup", "none,name=systemd", MS_NOSUID|MS_NOEXEC|MS_NODEV, false },
{ "proc", "/proc", "proc", NULL, MS_NOSUID|MS_NOEXEC|MS_NODEV, true, true },
{ "sysfs", "/sys", "sysfs", NULL, MS_NOSUID|MS_NOEXEC|MS_NODEV, true, true },
{ "devtmpfs", "/dev", "devtmpfs", "mode=755", MS_NOSUID|MS_STRICTATIME, true, true },
{ "securityfs", "/sys/kernel/security", "securityfs", NULL, MS_NOSUID|MS_NOEXEC|MS_NODEV, false, false },
{ "tmpfs", "/dev/shm", "tmpfs", "mode=1777", MS_NOSUID|MS_NODEV|MS_STRICTATIME, true, true },
{ "devpts", "/dev/pts", "devpts", "mode=620,gid=" STRINGIFY(TTY_GID), MS_NOSUID|MS_NOEXEC, false, true },
{ "tmpfs", "/run", "tmpfs", "mode=755", MS_NOSUID|MS_NODEV|MS_STRICTATIME, true, true },
{ "tmpfs", "/sys/fs/cgroup", "tmpfs", "mode=755", MS_NOSUID|MS_NOEXEC|MS_NODEV|MS_STRICTATIME, false, true },
{ "cgroup", "/sys/fs/cgroup/systemd", "cgroup", "none,name=systemd", MS_NOSUID|MS_NOEXEC|MS_NODEV, false, true },
};
/* These are API file systems that might be mounted by other software,
@ -86,10 +88,7 @@ static const char ignore_paths[] =
/* Container bind mounts */
"/proc/sys\0"
"/dev/console\0"
"/proc/kmsg\0"
"/etc/localtime\0"
"/etc/timezone\0"
"/etc/machine-id\0";
"/proc/kmsg\0";
bool mount_point_is_api(const char *path) {
unsigned i;
@ -123,12 +122,17 @@ static int mount_one(const MountPoint *p, bool relabel) {
if (relabel)
label_fix(p->where, true, true);
if ((r = path_is_mount_point(p->where, true)) < 0)
r = path_is_mount_point(p->where, true);
if (r < 0)
return r;
if (r > 0)
return 0;
/* Skip securityfs in a container */
if (!p->in_container && detect_container(NULL) > 0)
return 0;
/* The access mode here doesn't really matter too much, since
* the mounted file system will take precedence anyway. */
mkdir_p_label(p->where, 0755);
@ -406,8 +410,9 @@ int mount_setup(bool loaded_policy) {
* nspawn and the container tools work out of the box. If
* specific setups need other settings they can reset the
* propagation mode to private if needed. */
if (mount(NULL, "/", NULL, MS_REC|MS_SHARED, NULL) < 0)
log_warning("Failed to set up the root directory for shared mount propagation: %m");
if (detect_container(NULL) <= 0)
if (mount(NULL, "/", NULL, MS_REC|MS_SHARED, NULL) < 0)
log_warning("Failed to set up the root directory for shared mount propagation: %m");
/* Create a few directories we always want around */
mkdir_label("/run/systemd", 0755);