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/*
* Copyright (C) 2014, 2015 netblue30 (netblue30@yahoo.com)
*
* This file is part of firejail project
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program 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 General Public License for more details.
*
* You should have received a copy of the GNU General Public License along
* with this program; if not, write to the Free Software Foundation, Inc.,
* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
*/
#include "firejail.h"
#include <sys/mount.h>
#include <sys/stat.h>
#include <linux/limits.h>
#include <glob.h>
#include <dirent.h>
#include <fcntl.h>
#include <pwd.h>
void fs_trace_preload(void) {
struct stat s;
// create an empty /etc/ld.so.preload
if (stat("/etc/ld.so.preload", &s)) {
if (arg_debug)
printf("Creating an empty /etc/ld.so.preload file\n");
/* coverity[toctou] */
FILE *fp = fopen("/etc/ld.so.preload", "w");
if (!fp)
errExit("fopen");
fclose(fp);
if (chown("/etc/ld.so.preload", 0, 0) < 0)
errExit("chown");
if (chmod("/etc/ld.so.preload", S_IRUSR | S_IWRITE | S_IRGRP | S_IROTH ) < 0)
errExit("chmod");
}
}
void fs_trace(void) {
// create /tmp/firejail/mnt directory
fs_build_mnt_dir();
// create the new ld.so.preload file and mount-bind it
if (arg_debug)
printf("Create the new ld.so.preload file\n");
char *preload;
if (asprintf(&preload, "%s/ld.so.preload", MNT_DIR) == -1)
errExit("asprintf");
FILE *fp = fopen(preload, "w");
if (!fp)
errExit("fopen");
fprintf(fp, "%s/lib/firejail/libtrace.so\n", PREFIX);
fclose(fp);
if (chown(preload, 0, 0) < 0)
errExit("chown");
if (chmod(preload, S_IRUSR | S_IWRITE | S_IRGRP | S_IROTH ) < 0)
errExit("chmod");
// mount the new preload file
if (arg_debug)
printf("Mount the new ld.so.preload file\n");
if (mount(preload, "/etc/ld.so.preload", NULL, MS_BIND|MS_REC, NULL) < 0)
errExit("mount bind ls.so.preload");
}
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