/* SPDX-License-Identifier: LGPL-2.1+ */
/***
- This file is part of systemd.
-
Copyright 2010 Lennart Poettering
-
- systemd is free software; you can redistribute it and/or modify it
- under the terms of the GNU Lesser General Public License as published by
- the Free Software Foundation; either version 2.1 of the License, or
- (at your option) any later version.
-
- systemd is distributed in the hope that it will be useful, but
- WITHOUT ANY WARRANTY; without even the implied warranty of
- MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
- Lesser General Public License for more details.
-
- You should have received a copy of the GNU Lesser General Public License
- along with systemd; If not, see <http://www.gnu.org/licenses/>.
***/
#include <errno.h>
#include <ftw.h>
#include <stdlib.h>
#include <sys/mount.h>
+#include <sys/statvfs.h>
#include <unistd.h>
#include "alloc-util.h"
#include "virt.h"
typedef enum MountMode {
- MNT_NONE = 0,
- MNT_FATAL = 1 << 0,
- MNT_IN_CONTAINER = 1 << 1,
- MNT_CHECK_WRITABLE = 1 << 2,
+ MNT_NONE = 0,
+ MNT_FATAL = 1 << 0,
+ MNT_IN_CONTAINER = 1 << 1,
+ MNT_CHECK_WRITABLE = 1 << 2,
} MountMode;
typedef struct MountPoint {
#endif
{ "tmpfs", "/run", "tmpfs", "mode=755", MS_NOSUID|MS_NODEV|MS_STRICTATIME,
NULL, MNT_FATAL|MNT_IN_CONTAINER },
- { "cgroup", "/sys/fs/cgroup", "cgroup2", "nsdelegate", MS_NOSUID|MS_NOEXEC|MS_NODEV,
+ { "cgroup2", "/sys/fs/cgroup", "cgroup2", "nsdelegate", MS_NOSUID|MS_NOEXEC|MS_NODEV,
cg_is_unified_wanted, MNT_IN_CONTAINER|MNT_CHECK_WRITABLE },
- { "cgroup", "/sys/fs/cgroup", "cgroup2", NULL, MS_NOSUID|MS_NOEXEC|MS_NODEV,
+ { "cgroup2", "/sys/fs/cgroup", "cgroup2", NULL, MS_NOSUID|MS_NOEXEC|MS_NODEV,
cg_is_unified_wanted, MNT_IN_CONTAINER|MNT_CHECK_WRITABLE },
{ "tmpfs", "/sys/fs/cgroup", "tmpfs", "mode=755", MS_NOSUID|MS_NOEXEC|MS_NODEV|MS_STRICTATIME,
cg_is_legacy_wanted, MNT_FATAL|MNT_IN_CONTAINER },
- { "cgroup", "/sys/fs/cgroup/unified", "cgroup2", "nsdelegate", MS_NOSUID|MS_NOEXEC|MS_NODEV,
+ { "cgroup2", "/sys/fs/cgroup/unified", "cgroup2", "nsdelegate", MS_NOSUID|MS_NOEXEC|MS_NODEV,
cg_is_hybrid_wanted, MNT_IN_CONTAINER|MNT_CHECK_WRITABLE },
- { "cgroup", "/sys/fs/cgroup/unified", "cgroup2", NULL, MS_NOSUID|MS_NOEXEC|MS_NODEV,
+ { "cgroup2", "/sys/fs/cgroup/unified", "cgroup2", NULL, MS_NOSUID|MS_NOEXEC|MS_NODEV,
cg_is_hybrid_wanted, MNT_IN_CONTAINER|MNT_CHECK_WRITABLE },
{ "cgroup", "/sys/fs/cgroup/systemd", "cgroup", "none,name=systemd,xattr", MS_NOSUID|MS_NOEXEC|MS_NODEV,
cg_is_legacy_wanted, MNT_IN_CONTAINER },
{ "efivarfs", "/sys/firmware/efi/efivars", "efivarfs", NULL, MS_NOSUID|MS_NOEXEC|MS_NODEV,
is_efi_boot, MNT_NONE },
#endif
+ { "bpf", "/sys/fs/bpf", "bpf", "mode=700", MS_NOSUID|MS_NOEXEC|MS_NODEV,
+ NULL, MNT_NONE, },
};
/* These are API file systems that might be mounted by other software,
}
static int mount_one(const MountPoint *p, bool relabel) {
- int r;
+ int r, priority;
assert(p);
+ priority = (p->mode & MNT_FATAL) ? LOG_ERR : LOG_DEBUG;
+
if (p->condition_fn && !p->condition_fn())
return 0;
/* Relabel first, just in case */
if (relabel)
- (void) label_fix(p->where, true, true);
+ (void) label_fix(p->where, LABEL_IGNORE_ENOENT|LABEL_IGNORE_EROFS);
r = path_is_mount_point(p->where, NULL, AT_SYMLINK_FOLLOW);
if (r < 0 && r != -ENOENT) {
- log_full_errno((p->mode & MNT_FATAL) ? LOG_ERR : LOG_DEBUG, r, "Failed to determine whether %s is a mount point: %m", p->where);
+ log_full_errno(priority, r, "Failed to determine whether %s is a mount point: %m", p->where);
return (p->mode & MNT_FATAL) ? r : 0;
}
if (r > 0)
p->type,
p->flags,
p->options) < 0) {
- log_full_errno((p->mode & MNT_FATAL) ? LOG_ERR : LOG_DEBUG, errno, "Failed to mount %s at %s: %m", p->type, p->where);
+ log_full_errno(priority, errno, "Failed to mount %s at %s: %m", p->type, p->where);
return (p->mode & MNT_FATAL) ? -errno : 0;
}
/* Relabel again, since we now mounted something fresh here */
if (relabel)
- (void) label_fix(p->where, false, false);
+ (void) label_fix(p->where, 0);
if (p->mode & MNT_CHECK_WRITABLE) {
- r = access(p->where, W_OK);
- if (r < 0) {
+ if (access(p->where, W_OK) < 0) {
+ r = -errno;
+
(void) umount(p->where);
(void) rmdir(p->where);
+
+ log_full_errno(priority, r, "Mount point %s not writable after mounting: %m", p->where);
return (p->mode & MNT_FATAL) ? r : 0;
}
}
int mount_cgroup_controllers(char ***join_controllers) {
_cleanup_set_free_free_ Set *controllers = NULL;
+ bool has_argument = !!join_controllers;
int r;
if (!cg_is_legacy_wanted())
/* Mount all available cgroup controllers that are built into the kernel. */
+ if (!has_argument)
+ /* The defaults:
+ * mount "cpu" + "cpuacct" together, and "net_cls" + "net_prio".
+ *
+ * We'd like to add "cpuset" to the mix, but "cpuset" doesn't really
+ * work for groups with no initialized attributes.
+ */
+ join_controllers = (char**[]) {
+ STRV_MAKE("cpu", "cpuacct"),
+ STRV_MAKE("net_cls", "net_prio"),
+ NULL,
+ };
+
r = cg_kernel_controllers(&controllers);
if (r < 0)
return log_error_errno(r, "Failed to enumerate cgroup controllers: %m");
if (!controller)
break;
- if (join_controllers)
- for (k = join_controllers; *k; k++)
- if (strv_find(*k, controller))
- break;
+ for (k = join_controllers; *k; k++)
+ if (strv_find(*k, controller))
+ break;
- if (k && *k) {
+ if (*k) {
char **i, **j;
for (i = *k, j = *k; *i; i++) {
t = set_remove(controllers, *i);
if (!t) {
- free(*i);
+ if (has_argument)
+ free(*i);
continue;
}
}
options = strv_join(*k, ",");
if (!options)
return log_oom();
- } else {
- options = controller;
- controller = NULL;
- }
+ } else
+ options = TAKE_PTR(controller);
where = strappend("/sys/fs/cgroup/", options);
if (!where)
if (r < 0)
return r;
- if (r > 0 && k && *k) {
+ if (r > 0 && *k) {
char **i;
for (i = *k; *i; i++) {
if (_unlikely_(ftwbuf->level == 0))
return FTW_CONTINUE;
- label_fix(fpath, false, false);
+ (void) label_fix(fpath, 0);
/* /run/initramfs is static data and big, no need to
* dynamically relabel its contents at boot... */
return FTW_CONTINUE;
};
+
+static int relabel_cgroup_filesystems(void) {
+ int r;
+ struct statfs st;
+
+ r = cg_all_unified();
+ if (r == 0) {
+ /* Temporarily remount the root cgroup filesystem to give it a proper label. Do this
+ only when the filesystem has been already populated by a previous instance of systemd
+ running from initrd. Otherwise don't remount anything and leave the filesystem read-write
+ for the cgroup filesystems to be mounted inside. */
+ if (statfs("/sys/fs/cgroup", &st) < 0)
+ return log_error_errno(errno, "Failed to determine mount flags for /sys/fs/cgroup: %m");
+
+ if (st.f_flags & ST_RDONLY)
+ (void) mount(NULL, "/sys/fs/cgroup", NULL, MS_REMOUNT, NULL);
+
+ (void) label_fix("/sys/fs/cgroup", 0);
+ (void) nftw("/sys/fs/cgroup", nftw_cb, 64, FTW_MOUNT|FTW_PHYS|FTW_ACTIONRETVAL);
+
+ if (st.f_flags & ST_RDONLY)
+ (void) mount(NULL, "/sys/fs/cgroup", NULL, MS_REMOUNT|MS_RDONLY, NULL);
+
+ } else if (r < 0)
+ return log_error_errno(r, "Failed to determine whether we are in all unified mode: %m");
+
+ return 0;
+}
#endif
int mount_setup(bool loaded_policy) {
before_relabel = now(CLOCK_MONOTONIC);
- nftw("/dev", nftw_cb, 64, FTW_MOUNT|FTW_PHYS|FTW_ACTIONRETVAL);
- nftw("/dev/shm", nftw_cb, 64, FTW_MOUNT|FTW_PHYS|FTW_ACTIONRETVAL);
- nftw("/run", nftw_cb, 64, FTW_MOUNT|FTW_PHYS|FTW_ACTIONRETVAL);
+ (void) nftw("/dev", nftw_cb, 64, FTW_MOUNT|FTW_PHYS|FTW_ACTIONRETVAL);
+ (void) nftw("/dev/shm", nftw_cb, 64, FTW_MOUNT|FTW_PHYS|FTW_ACTIONRETVAL);
+ (void) nftw("/run", nftw_cb, 64, FTW_MOUNT|FTW_PHYS|FTW_ACTIONRETVAL);
+
+ r = relabel_cgroup_filesystems();
+ if (r < 0)
+ return r;
after_relabel = now(CLOCK_MONOTONIC);
- log_info("Relabelled /dev and /run in %s.",
+ log_info("Relabelled /dev, /run and /sys/fs/cgroup in %s.",
format_timespan(timespan, sizeof(timespan), after_relabel - before_relabel, 0));
}
#endif
(void) mkdir_label("/run/systemd", 0755);
(void) mkdir_label("/run/systemd/system", 0755);
- /* Set up inaccessible items */
+ /* Set up inaccessible (and empty) file nodes of all types */
(void) mkdir_label("/run/systemd/inaccessible", 0000);
(void) mknod("/run/systemd/inaccessible/reg", S_IFREG | 0000, 0);
(void) mkdir_label("/run/systemd/inaccessible/dir", 0000);
- (void) mknod("/run/systemd/inaccessible/chr", S_IFCHR | 0000, makedev(0, 0));
- (void) mknod("/run/systemd/inaccessible/blk", S_IFBLK | 0000, makedev(0, 0));
(void) mkfifo("/run/systemd/inaccessible/fifo", 0000);
(void) mknod("/run/systemd/inaccessible/sock", S_IFSOCK | 0000, 0);
+ /* The following two are likely to fail if we lack the privs for it (for example in an userns environment, if
+ * CAP_SYS_MKNOD is missing, or if a device node policy prohibit major/minor of 0 device nodes to be
+ * created). But that's entirely fine. Consumers of these files should carry fallback to use a different node
+ * then, for example /run/systemd/inaccessible/sock, which is close enough in behaviour and semantics for most
+ * uses. */
+ (void) mknod("/run/systemd/inaccessible/chr", S_IFCHR | 0000, makedev(0, 0));
+ (void) mknod("/run/systemd/inaccessible/blk", S_IFBLK | 0000, makedev(0, 0));
+
return 0;
}