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diff --git a/man2/chroot.2 b/man2/chroot.2 deleted file mode 100644 index 72a75fb40..000000000 --- a/man2/chroot.2 +++ /dev/null @@ -1,166 +0,0 @@ -.\" Copyright (c) 1992 Drew Eckhardt (drew@cs.colorado.edu), March 28, 1992 -.\" -.\" SPDX-License-Identifier: Linux-man-pages-copyleft -.\" -.\" Modified by Michael Haardt <michael@moria.de> -.\" Modified 1993-07-21 by Rik Faith <faith@cs.unc.edu> -.\" Modified 1994-08-21 by Michael Chastain <mec@shell.portal.com> -.\" Modified 1996-06-13 by aeb -.\" Modified 1996-11-06 by Eric S. Raymond <esr@thyrsus.com> -.\" Modified 1997-08-21 by Joseph S. Myers <jsm28@cam.ac.uk> -.\" Modified 2004-06-23 by Michael Kerrisk <mtk.manpages@gmail.com> -.\" -.TH chroot 2 (date) "Linux man-pages (unreleased)" -.SH NAME -chroot \- change root directory -.SH LIBRARY -Standard C library -.RI ( libc ", " \-lc ) -.SH SYNOPSIS -.nf -.B #include <unistd.h> -.P -.BI "int chroot(const char *" path ); -.fi -.P -.RS -4 -Feature Test Macro Requirements for glibc (see -.BR feature_test_macros (7)): -.RE -.P -.BR chroot (): -.nf - Since glibc 2.2.2: - _XOPEN_SOURCE && ! (_POSIX_C_SOURCE >= 200112L) - || /* Since glibc 2.20: */ _DEFAULT_SOURCE - || /* glibc <= 2.19: */ _BSD_SOURCE - Before glibc 2.2.2: - none -.fi -.SH DESCRIPTION -.BR chroot () -changes the root directory of the calling process to that specified in -.IR path . -This directory will be used for pathnames beginning with \fI/\fP. -The root directory is inherited by all children of the calling process. -.P -Only a privileged process (Linux: one with the -.B CAP_SYS_CHROOT -capability in its user namespace) may call -.BR chroot (). -.P -This call changes an ingredient in the pathname resolution process -and does nothing else. -In particular, it is not intended to be used -for any kind of security purpose, neither to fully sandbox a process nor -to restrict filesystem system calls. -In the past, -.BR chroot () -has been used by daemons to restrict themselves prior to passing paths -supplied by untrusted users to system calls such as -.BR open (2). -However, if a folder is moved out of the chroot directory, an attacker -can exploit that to get out of the chroot directory as well. -The easiest way to do that is to -.BR chdir (2) -to the to-be-moved directory, wait for it to be moved out, then open a -path like ../../../etc/passwd. -.P -.\" This is how the "slightly trickier variation" works: -.\" https://github.com/QubesOS/qubes-secpack/blob/master/QSBs/qsb-014-2015.txt#L142 -A slightly -trickier variation also works under some circumstances if -.BR chdir (2) -is not permitted. -If a daemon allows a "chroot directory" to be specified, -that usually means that if you want to prevent remote users from accessing -files outside the chroot directory, you must ensure that folders are never -moved out of it. -.P -This call does not change the current working directory, -so that after the call \[aq]\fI.\fP\[aq] can -be outside the tree rooted at \[aq]\fI/\fP\[aq]. -In particular, the superuser can escape from a "chroot jail" -by doing: -.P -.in +4n -.EX -mkdir foo; chroot foo; cd .. -.EE -.in -.P -This call does not close open file descriptors, and such file -descriptors may allow access to files outside the chroot tree. -.SH RETURN VALUE -On success, zero is returned. -On error, \-1 is returned, and -.I errno -is set to indicate the error. -.SH ERRORS -Depending on the filesystem, other errors can be returned. -The more general errors are listed below: -.TP -.B EACCES -Search permission is denied on a component of the path prefix. -(See also -.BR path_resolution (7).) -.\" Also search permission is required on the final component, -.\" maybe just to guarantee that it is a directory? -.TP -.B EFAULT -.I path -points outside your accessible address space. -.TP -.B EIO -An I/O error occurred. -.TP -.B ELOOP -Too many symbolic links were encountered in resolving -.IR path . -.TP -.B ENAMETOOLONG -.I path -is too long. -.TP -.B ENOENT -The file does not exist. -.TP -.B ENOMEM -Insufficient kernel memory was available. -.TP -.B ENOTDIR -A component of -.I path -is not a directory. -.TP -.B EPERM -The caller has insufficient privilege. -.SH STANDARDS -None. -.SH HISTORY -SVr4, 4.4BSD, SUSv2 (marked LEGACY). -This function is not part of POSIX.1-2001. -.\" SVr4 documents additional EINTR, ENOLINK and EMULTIHOP error conditions. -.\" X/OPEN does not document EIO, ENOMEM or EFAULT error conditions. -.SH NOTES -A child process created via -.BR fork (2) -inherits its parent's root directory. -The root directory is left unchanged by -.BR execve (2). -.P -The magic symbolic link, -.IR /proc/ pid /root , -can be used to discover a process's root directory; see -.BR proc (5) -for details. -.P -FreeBSD has a stronger -.BR jail () -system call. -.SH SEE ALSO -.BR chroot (1), -.BR chdir (2), -.BR pivot_root (2), -.BR path_resolution (7), -.BR switch_root (8) |