chroot — change root directory
#include <unistd.h>
int
chroot( |
const char * | path); |
chroot() changes the root
directory to that specified in path. This directory will be
used for pathnames beginning with /. The root directory is inherited by all
children of the calling process.
Only a privileged process (Linux: one with the
CAP_SYS_CHROOT capability) may
call chroot().
This call changes an ingredient in the pathname resolution process and does nothing else.
This call does not change the current working directory,
so that after the call '.' can
be outside the tree rooted at '/'. In particular, the superuser can escape
from a "chroot jail" by doing:
mkdir foo; chroot foo; cd ..
This call does not close open file descriptors, and such file descriptors may allow access to files outside the chroot tree.
On success, zero is returned. On error, −1 is
returned, and errno is set
appropriately.
Depending on the file system, other errors can be returned. The more general errors are listed below:
Search permission is denied on a component of the path prefix. (See also path_resolution(7).)
path points
outside your accessible address space.
An I/O error occurred.
Too many symbolic links were encountered in
resolving path.
path is too
long.
The file does not exist.
Insufficient kernel memory was available.
A component of path is not a
directory.
The caller has insufficient privilege.
A child process created via fork(2) inherits its parent's root directory. The root directory is left unchanged by execve(2).
FreeBSD has a stronger jail() system call.
This page is part of release 2.79 of the Linux man-pages project. A
description of the project, and information about reporting
bugs, can be found at
http://www.kernel.org/doc/man-pages/.
|
Copyright (c) 1992 Drew Eckhardt (drewcs.colorado.edu), March 28, 1992 Permission is granted to make and distribute verbatim copies of this manual provided the copyright notice and this permission notice are preserved on all copies. Permission is granted to copy and distribute modified versions of this manual under the conditions for verbatim copying, provided that the entire resulting derived work is distributed under the terms of a permission notice identical to this one. Since the Linux kernel and libraries are constantly changing, this manual page may be incorrect or out-of-date. The author(s) assume no responsibility for errors or omissions, or for damages resulting from the use of the information contained herein. The author(s) may not have taken the same level of care in the production of this manual, which is licensed free of charge, as they might when working professionally. Formatted or processed versions of this manual, if unaccompanied by the source, must acknowledge the copyright and authors of this work. Modified by Michael Haardt <michaelmoria.de> Modified 1993-07-21 by Rik Faith <faithcs.unc.edu> Modified 1994-08-21 by Michael Chastain <mecshell.portal.com> Modified 1996-06-13 by aeb Modified 1996-11-06 by Eric S. Raymond <esrthyrsus.com> Modified 1997-08-21 by Joseph S. Myers <jsm28cam.ac.uk> Modified 2004-06-23 by Michael Kerrisk <mtk.manpagesgmail.com> |