-/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
-
-/***
- 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/>.
-***/
+/* SPDX-License-Identifier: LGPL-2.1+ */
#include <errno.h>
#include <mntent.h>
#include <string.h>
+#include <sys/prctl.h>
#include <sys/stat.h>
#include <sys/wait.h>
#include <unistd.h>
+#include "env-util.h"
#include "exit-status.h"
#include "log.h"
+#include "main-func.h"
#include "mount-setup.h"
#include "mount-util.h"
#include "path-util.h"
+#include "process-util.h"
#include "signal-util.h"
+#include "strv.h"
#include "util.h"
-/* Goes through /etc/fstab and remounts all API file systems, applying
- * options that are in /etc/fstab that systemd might not have
- * respected */
+/* Goes through /etc/fstab and remounts all API file systems, applying options that are in /etc/fstab that systemd
+ * might not have respected */
-int main(int argc, char *argv[]) {
- int ret = EXIT_FAILURE;
- _cleanup_endmntent_ FILE *f = NULL;
- struct mntent* me;
- Hashmap *pids = NULL;
+static int track_pid(Hashmap **h, const char *path, pid_t pid) {
+ _cleanup_free_ char *c = NULL;
+ int r;
- if (argc > 1) {
- log_error("This program takes no argument.");
- return EXIT_FAILURE;
- }
+ assert(h);
+ assert(path);
+ assert(pid_is_valid(pid));
- log_set_target(LOG_TARGET_AUTO);
- log_parse_environment();
- log_open();
+ r = hashmap_ensure_allocated(h, NULL);
+ if (r < 0)
+ return log_oom();
- umask(0022);
+ c = strdup(path);
+ if (!c)
+ return log_oom();
- f = setmntent("/etc/fstab", "r");
- if (!f) {
- if (errno == ENOENT)
- return EXIT_SUCCESS;
+ r = hashmap_put(*h, PID_TO_PTR(pid), c);
+ if (r < 0)
+ return log_oom();
- log_error_errno(errno, "Failed to open /etc/fstab: %m");
- return EXIT_FAILURE;
- }
+ TAKE_PTR(c);
+ return 0;
+}
- pids = hashmap_new(NULL);
- if (!pids) {
- log_error("Failed to allocate set");
- goto finish;
+static int do_remount(const char *path, bool force_rw, Hashmap **pids) {
+ pid_t pid;
+ int r;
+
+ log_debug("Remounting %s...", path);
+
+ r = safe_fork(force_rw ? "(remount-rw)" : "(remount)",
+ FORK_RESET_SIGNALS|FORK_DEATHSIG|FORK_RLIMIT_NOFILE_SAFE|FORK_LOG, &pid);
+ if (r < 0)
+ return r;
+ if (r == 0) {
+ /* Child */
+ execv(MOUNT_PATH,
+ STRV_MAKE(MOUNT_PATH,
+ path,
+ "-o",
+ force_rw ? "remount,rw" : "remount"));
+ log_error_errno(errno, "Failed to execute " MOUNT_PATH ": %m");
+ _exit(EXIT_FAILURE);
}
- ret = EXIT_SUCCESS;
-
- while ((me = getmntent(f))) {
- pid_t pid;
- int k;
- char *s;
-
- /* Remount the root fs, /usr and all API VFS */
- if (!mount_point_is_api(me->mnt_dir) &&
- !path_equal(me->mnt_dir, "/") &&
- !path_equal(me->mnt_dir, "/usr"))
- continue;
+ /* Parent */
+ return track_pid(pids, path, pid);
+}
- log_debug("Remounting %s", me->mnt_dir);
+static int run(int argc, char *argv[]) {
+ _cleanup_hashmap_free_free_ Hashmap *pids = NULL;
+ _cleanup_endmntent_ FILE *f = NULL;
+ bool has_root = false;
+ struct mntent* me;
+ int r;
- pid = fork();
- if (pid < 0) {
- log_error_errno(errno, "Failed to fork: %m");
- ret = EXIT_FAILURE;
- continue;
- }
+ log_setup_service();
- if (pid == 0) {
- const char *arguments[5];
- /* Child */
+ if (argc > 1)
+ return log_error_errno(SYNTHETIC_ERRNO(EINVAL),
+ "This program takes no arguments.");
- (void) reset_all_signal_handlers();
- (void) reset_signal_mask();
+ umask(0022);
- arguments[0] = MOUNT_PATH;
- arguments[1] = me->mnt_dir;
- arguments[2] = "-o";
- arguments[3] = "remount";
- arguments[4] = NULL;
+ f = setmntent("/etc/fstab", "re");
+ if (!f) {
+ if (errno != ENOENT)
+ return log_error_errno(errno, "Failed to open /etc/fstab: %m");
+ } else
+ while ((me = getmntent(f))) {
+ /* Remount the root fs, /usr, and all API VFSs */
+ if (!mount_point_is_api(me->mnt_dir) &&
+ !PATH_IN_SET(me->mnt_dir, "/", "/usr"))
+ continue;
- execv(MOUNT_PATH, (char **) arguments);
+ if (path_equal(me->mnt_dir, "/"))
+ has_root = true;
- log_error_errno(errno, "Failed to execute " MOUNT_PATH ": %m");
- _exit(EXIT_FAILURE);
+ r = do_remount(me->mnt_dir, false, &pids);
+ if (r < 0)
+ return r;
}
- /* Parent */
-
- s = strdup(me->mnt_dir);
- if (!s) {
- log_oom();
- ret = EXIT_FAILURE;
- continue;
- }
+ if (!has_root) {
+ /* The $SYSTEMD_REMOUNT_ROOT_RW environment variable is set by systemd-gpt-auto-generator to tell us
+ * whether to remount things. We honour it only if there's no explicit line in /etc/fstab configured
+ * which takes precedence. */
+ r = getenv_bool("SYSTEMD_REMOUNT_ROOT_RW");
+ if (r < 0 && r != -ENXIO)
+ log_warning_errno(r, "Failed to parse $SYSTEMD_REMOUNT_ROOT_RW, ignoring: %m");
- k = hashmap_put(pids, UINT_TO_PTR(pid), s);
- if (k < 0) {
- log_error_errno(k, "Failed to add PID to set: %m");
- ret = EXIT_FAILURE;
- continue;
+ if (r > 0) {
+ r = do_remount("/", true, &pids);
+ if (r < 0)
+ return r;
}
}
+ r = 0;
while (!hashmap_isempty(pids)) {
+ _cleanup_free_ char *s = NULL;
siginfo_t si = {};
- char *s;
if (waitid(P_ALL, 0, &si, WEXITED) < 0) {
-
if (errno == EINTR)
continue;
- log_error_errno(errno, "waitid() failed: %m");
- ret = EXIT_FAILURE;
- break;
+ return log_error_errno(errno, "waitid() failed: %m");
}
- s = hashmap_remove(pids, UINT_TO_PTR(si.si_pid));
- if (s) {
- if (!is_clean_exit(si.si_code, si.si_status, NULL)) {
- if (si.si_code == CLD_EXITED)
- log_error(MOUNT_PATH " for %s exited with exit status %i.", s, si.si_status);
- else
- log_error(MOUNT_PATH " for %s terminated by signal %s.", s, signal_to_string(si.si_status));
-
- ret = EXIT_FAILURE;
- }
+ s = hashmap_remove(pids, PID_TO_PTR(si.si_pid));
+ if (s &&
+ !is_clean_exit(si.si_code, si.si_status, EXIT_CLEAN_COMMAND, NULL)) {
+ if (si.si_code == CLD_EXITED)
+ log_error(MOUNT_PATH " for %s exited with exit status %i.", s, si.si_status);
+ else
+ log_error(MOUNT_PATH " for %s terminated by signal %s.", s, signal_to_string(si.si_status));
- free(s);
+ r = -ENOEXEC;
}
}
-finish:
-
- if (pids)
- hashmap_free_free(pids);
-
- return ret;
+ return r;
}
+
+DEFINE_MAIN_FUNCTION(run);