chiark / gitweb /
core: always create /dev/kdbus/ns (and make it private 0700) after setting up the...
[elogind.git] / src / core / mount-setup.c
index c26dedca60a466b5fc24f0bff5440565ba6c42d2..c601c9742c7d3fd249a54d59093b01f075c61c2a 100644 (file)
 #include "strv.h"
 #include "mkdir.h"
 #include "path-util.h"
+#include "missing.h"
+#include "virt.h"
+#include "efivars.h"
+#include "smack-util.h"
 
 #ifndef TTY_GID
 #define TTY_GID 5
 #endif
 
+typedef enum MountMode {
+        MNT_NONE  =        0,
+        MNT_FATAL =        1 <<  0,
+        MNT_IN_CONTAINER = 1 <<  1,
+} MountMode;
+
 typedef struct MountPoint {
         const char *what;
         const char *where;
         const char *type;
         const char *options;
         unsigned long flags;
-        bool fatal;
+        bool (*condition_fn)(void);
+        MountMode mode;
 } MountPoint;
 
 /* The first three entries we might need before SELinux is up. The
  * fourth (securityfs) is needed by IMA to load a custom policy. The
  * other ones we can delay until SELinux and IMA are loaded. */
-#define N_EARLY_MOUNT 4
+#define N_EARLY_MOUNT 5
 
 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,
+          NULL,       MNT_FATAL|MNT_IN_CONTAINER },
+        { "sysfs",      "/sys",                      "sysfs",      NULL, MS_NOSUID|MS_NOEXEC|MS_NODEV,
+          NULL,       MNT_FATAL|MNT_IN_CONTAINER },
+        { "devtmpfs",   "/dev",                      "devtmpfs",   "mode=755", MS_NOSUID|MS_STRICTATIME,
+          NULL,       MNT_FATAL|MNT_IN_CONTAINER },
+        { "securityfs", "/sys/kernel/security",      "securityfs", NULL, MS_NOSUID|MS_NOEXEC|MS_NODEV,
+          NULL,       MNT_NONE },
+#ifdef HAVE_SMACK
+        { "smackfs",    "/sys/fs/smackfs",           "smackfs",    "smackfsdef=*", MS_NOSUID|MS_NOEXEC|MS_NODEV|MS_STRICTATIME,
+          use_smack,  MNT_FATAL },
+        { "tmpfs",      "/dev/shm",                  "tmpfs",      "mode=1777,smackfsroot=*", MS_NOSUID|MS_NODEV|MS_STRICTATIME,
+          use_smack,  MNT_FATAL },
+#endif
+        { "tmpfs",      "/dev/shm",                  "tmpfs",      "mode=1777", MS_NOSUID|MS_NODEV|MS_STRICTATIME,
+          NULL,       MNT_FATAL|MNT_IN_CONTAINER },
+        { "devpts",     "/dev/pts",                  "devpts",     "mode=620,gid=" STRINGIFY(TTY_GID), MS_NOSUID|MS_NOEXEC,
+          NULL,       MNT_IN_CONTAINER },
+#ifdef HAVE_SMACK
+        { "tmpfs",      "/run",                      "tmpfs",      "mode=755,smackfsroot=*", MS_NOSUID|MS_NODEV|MS_STRICTATIME,
+          use_smack,  MNT_FATAL },
+#endif
+        { "tmpfs",      "/run",                      "tmpfs",      "mode=755", MS_NOSUID|MS_NODEV|MS_STRICTATIME,
+          NULL,       MNT_FATAL|MNT_IN_CONTAINER },
+        { "tmpfs",      "/sys/fs/cgroup",            "tmpfs",      "mode=755", MS_NOSUID|MS_NOEXEC|MS_NODEV|MS_STRICTATIME,
+          NULL,       MNT_IN_CONTAINER },
+#ifdef HAVE_XATTR
+        { "cgroup",     "/sys/fs/cgroup/systemd",    "cgroup",     "none,name=systemd,xattr", MS_NOSUID|MS_NOEXEC|MS_NODEV,
+          NULL,       MNT_IN_CONTAINER },
+#endif
+        { "cgroup",     "/sys/fs/cgroup/systemd",    "cgroup",     "none,name=systemd", MS_NOSUID|MS_NOEXEC|MS_NODEV,
+          NULL,       MNT_IN_CONTAINER },
+        { "pstore",     "/sys/fs/pstore",            "pstore",     NULL, MS_NOSUID|MS_NOEXEC|MS_NODEV,
+          NULL,       MNT_NONE },
+#ifdef ENABLE_EFI
+        { "efivarfs",   "/sys/firmware/efi/efivars", "efivarfs",   NULL, MS_NOSUID|MS_NOEXEC|MS_NODEV,
+          is_efi_boot, MNT_NONE },
+#endif
 };
 
 /* These are API file systems that might be mounted by other software,
@@ -85,10 +125,7 @@ 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;
@@ -118,16 +155,24 @@ static int mount_one(const MountPoint *p, bool relabel) {
 
         assert(p);
 
+        if (p->condition_fn && !p->condition_fn())
+                return 0;
+
         /* Relabel first, just in case */
         if (relabel)
-                label_fix(p->where, true);
+                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->mode & MNT_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);
@@ -143,13 +188,13 @@ static int mount_one(const MountPoint *p, bool relabel) {
                   p->type,
                   p->flags,
                   p->options) < 0) {
-                log_full(p->fatal ? LOG_ERR : LOG_DEBUG, "Failed to mount %s: %s", p->where, strerror(errno));
-                return p->fatal ? -errno : 0;
+                log_full((p->mode & MNT_FATAL) ? LOG_ERR : LOG_DEBUG, "Failed to mount %s: %m", p->where);
+                return (p->mode & MNT_FATAL) ? -errno : 0;
         }
 
         /* Relabel again, since we now mounted something fresh here */
         if (relabel)
-                label_fix(p->where, false);
+                label_fix(p->where, false, false);
 
         return 1;
 }
@@ -175,9 +220,9 @@ int mount_setup_early(void) {
 
 int mount_cgroup_controllers(char ***join_controllers) {
         int r;
-        FILE *f;
         char buf[LINE_MAX];
-        Set *controllers;
+        _cleanup_set_free_free_ Set *controllers = NULL;
+        _cleanup_fclose_ FILE *f;
 
         /* Mount all available cgroup controllers that are built into the kernel. */
 
@@ -188,11 +233,8 @@ int mount_cgroup_controllers(char ***join_controllers) {
         }
 
         controllers = set_new(string_hash_func, string_compare_func);
-        if (!controllers) {
-                r = -ENOMEM;
-                log_error("Failed to allocate controller set.");
-                goto finish;
-        }
+        if (!controllers)
+                return log_oom();
 
         /* Ignore the header line */
         (void) fgets(buf, sizeof(buf), f);
@@ -207,8 +249,7 @@ int mount_cgroup_controllers(char ***join_controllers) {
                                 break;
 
                         log_error("Failed to parse /proc/cgroups.");
-                        r = -EIO;
-                        goto finish;
+                        return -EIO;
                 }
 
                 if (!enabled) {
@@ -216,18 +257,22 @@ int mount_cgroup_controllers(char ***join_controllers) {
                         continue;
                 }
 
-                r = set_put(controllers, controller);
+                r = set_consume(controllers, controller);
                 if (r < 0) {
                         log_error("Failed to add controller to set.");
-                        free(controller);
-                        goto finish;
+                        return r;
                 }
         }
 
         for (;;) {
-                MountPoint p;
-                char *controller, *where, *options;
+                MountPoint p = {
+                        .what = "cgroup",
+                        .type = "cgroup",
+                        .flags = MS_NOSUID|MS_NOEXEC|MS_NODEV,
+                        .mode = MNT_IN_CONTAINER,
+                };
                 char ***k = NULL;
+                _cleanup_free_ char *options = NULL, *controller;
 
                 controller = set_steal_first(controllers);
                 if (!controller)
@@ -244,14 +289,13 @@ int mount_cgroup_controllers(char ***join_controllers) {
                         for (i = *k, j = *k; *i; i++) {
 
                                 if (!streq(*i, controller)) {
-                                        char *t;
+                                        char _cleanup_free_ *t;
 
                                         t = set_remove(controllers, *i);
                                         if (!t) {
                                                 free(*i);
                                                 continue;
                                         }
-                                        free(t);
                                 }
 
                                 *(j++) = *i;
@@ -260,80 +304,36 @@ int mount_cgroup_controllers(char ***join_controllers) {
                         *j = NULL;
 
                         options = strv_join(*k, ",");
-                        if (!options) {
-                                log_error("Failed to join options");
-                                free(controller);
-                                r = -ENOMEM;
-                                goto finish;
-                        }
-
+                        if (!options)
+                                return log_oom();
                 } else {
                         options = controller;
                         controller = NULL;
                 }
 
-                where = strappend("/sys/fs/cgroup/", options);
-                if (!where) {
-                        log_error("Failed to build path");
-                        free(options);
-                        r = -ENOMEM;
-                        goto finish;
-                }
-
-                zero(p);
-                p.what = "cgroup";
-                p.where = where;
-                p.type = "cgroup";
+                p.where = strappenda("/sys/fs/cgroup/", options);
                 p.options = options;
-                p.flags = MS_NOSUID|MS_NOEXEC|MS_NODEV;
-                p.fatal = false;
 
                 r = mount_one(&p, true);
-                free(controller);
-                free(where);
-
-                if (r < 0) {
-                        free(options);
-                        goto finish;
-                }
+                if (r < 0)
+                        return r;
 
                 if (r > 0 && k && *k) {
                         char **i;
 
                         for (i = *k; *i; i++) {
-                                char *t;
-
-                                t = strappend("/sys/fs/cgroup/", *i);
-                                if (!t) {
-                                        log_error("Failed to build path");
-                                        r = -ENOMEM;
-                                        free(options);
-                                        goto finish;
-                                }
+                                char *t = strappenda("/sys/fs/cgroup/", *i);
 
                                 r = symlink(options, t);
-                                free(t);
-
                                 if (r < 0 && errno != EEXIST) {
-                                        log_error("Failed to create symlink: %m");
-                                        r = -errno;
-                                        free(options);
-                                        goto finish;
+                                        log_error("Failed to create symlink %s: %m", t);
+                                        return -errno;
                                 }
                         }
                 }
-
-                free(options);
         }
 
-        r = 0;
-
-finish:
-        set_free_free(controllers);
-
-        fclose(f);
-
-        return r;
+        return 0;
 }
 
 static int nftw_cb(
@@ -346,7 +346,7 @@ static int nftw_cb(
         if (_unlikely_(ftwbuf->level == 0))
                 return FTW_CONTINUE;
 
-        label_fix(fpath, true);
+        label_fix(fpath, false, false);
 
         /* /run/initramfs is static data and big, no need to
          * dynamically relabel its contents at boot... */
@@ -359,14 +359,8 @@ static int nftw_cb(
 };
 
 int mount_setup(bool loaded_policy) {
-
-        static const char relabel[] =
-                "/run/initramfs/root-fsck\0"
-                "/run/initramfs/shutdown\0";
-
         int r;
         unsigned i;
-        const char *j;
 
         for (i = 0; i < ELEMENTSOF(mount_table); i ++) {
                 r = mount_one(mount_table + i, true);
@@ -388,24 +382,35 @@ int mount_setup(bool loaded_policy) {
                 nftw("/dev", nftw_cb, 64, FTW_MOUNT|FTW_PHYS|FTW_ACTIONRETVAL);
                 nftw("/run", nftw_cb, 64, FTW_MOUNT|FTW_PHYS|FTW_ACTIONRETVAL);
 
-                /* Explicitly relabel these */
-                NULSTR_FOREACH(j, relabel)
-                        label_fix(j, true);
-
                 after_relabel = now(CLOCK_MONOTONIC);
 
                 log_info("Relabelled /dev and /run in %s.",
-                         format_timespan(timespan, sizeof(timespan), after_relabel - before_relabel));
+                         format_timespan(timespan, sizeof(timespan), after_relabel - before_relabel, 0));
         }
 
         /* Create a few default symlinks, which are normally created
          * by udevd, but some scripts might need them before we start
          * udevd. */
-        dev_setup();
-
-        /* Create a few directories we always want around */
+        dev_setup(NULL);
+
+        /* Mark the root directory as shared in regards to mount
+         * propagation. The kernel defaults to "private", but we think
+         * it makes more sense to have a default of "shared" so that
+         * 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 (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, Note that
+         * sd_booted() checks for /run/systemd/system, so this mkdir
+         * really needs to stay for good, otherwise software that
+         * copied sd-daemon.c into their sources will misdetect
+         * systemd. */
         mkdir_label("/run/systemd", 0755);
         mkdir_label("/run/systemd/system", 0755);
+        mkdir_label("/run/systemd/inaccessible", 0000);
 
         return 0;
 }