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Diffstat (limited to 'man2/setreuid.2')
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diff --git a/man2/setreuid.2 b/man2/setreuid.2 deleted file mode 100644 index e887619..0000000 --- a/man2/setreuid.2 +++ /dev/null @@ -1,193 +0,0 @@ -.\" Copyright (c) 1983, 1991 The Regents of the University of California. -.\" and Copyright (C) 2009, 2010, 2014, 2015, Michael Kerrisk <mtk.manpages@gmail.com> -.\" All rights reserved. -.\" -.\" SPDX-License-Identifier: BSD-4-Clause-UC -.\" -.\" @(#)setregid.2 6.4 (Berkeley) 3/10/91 -.\" -.\" Modified Sat Jul 24 09:08:49 1993 by Rik Faith <faith@cs.unc.edu> -.\" Portions extracted from linux/kernel/sys.c: -.\" Copyright (C) 1991, 1992 Linus Torvalds -.\" May be distributed under the GNU General Public License -.\" Changes: 1994-07-29 by Wilf <G.Wilford@ee.surrey.ac.uk> -.\" 1994-08-02 by Wilf due to change in kernel. -.\" 2004-07-04 by aeb -.\" 2004-05-27 by Michael Kerrisk -.\" -.TH setreuid 2 2023-10-31 "Linux man-pages 6.7" -.SH NAME -setreuid, setregid \- set real and/or effective user or group ID -.SH LIBRARY -Standard C library -.RI ( libc ", " \-lc ) -.SH SYNOPSIS -.nf -.B #include <unistd.h> -.P -.BI "int setreuid(uid_t " ruid ", uid_t " euid ); -.BI "int setregid(gid_t " rgid ", gid_t " egid ); -.fi -.P -.RS -4 -Feature Test Macro Requirements for glibc (see -.BR feature_test_macros (7)): -.RE -.P -.BR setreuid (), -.BR setregid (): -.nf - _XOPEN_SOURCE >= 500 -.\" || _XOPEN_SOURCE && _XOPEN_SOURCE_EXTENDED - || /* Since glibc 2.19: */ _DEFAULT_SOURCE - || /* glibc <= 2.19: */ _BSD_SOURCE -.fi -.SH DESCRIPTION -.BR setreuid () -sets real and effective user IDs of the calling process. -.P -Supplying a value of \-1 for either the real or effective user ID forces -the system to leave that ID unchanged. -.P -Unprivileged processes may only set the effective user ID to the real user ID, -the effective user ID, or the saved set-user-ID. -.P -Unprivileged users may only set the real user ID to -the real user ID or the effective user ID. -.P -If the real user ID is set (i.e., -.I ruid -is not \-1) or the effective user ID is set to a value -not equal to the previous real user ID, -the saved set-user-ID will be set to the new effective user ID. -.P -Completely analogously, -.BR setregid () -sets real and effective group ID's of the calling process, -and all of the above holds with "group" instead of "user". -.SH RETURN VALUE -On success, zero is returned. -On error, \-1 is returned, and -.I errno -is set to indicate the error. -.P -.IR Note : -there are cases where -.BR setreuid () -can fail even when the caller is UID 0; -it is a grave security error to omit checking for a failure return from -.BR setreuid (). -.SH ERRORS -.TP -.B EAGAIN -The call would change the caller's real UID (i.e., -.I ruid -does not match the caller's real UID), -but there was a temporary failure allocating the -necessary kernel data structures. -.TP -.B EAGAIN -.I ruid -does not match the caller's real UID and this call would -bring the number of processes belonging to the real user ID -.I ruid -over the caller's -.B RLIMIT_NPROC -resource limit. -Since Linux 3.1, this error case no longer occurs -(but robust applications should check for this error); -see the description of -.B EAGAIN -in -.BR execve (2). -.TP -.B EINVAL -One or more of the target user or group IDs -is not valid in this user namespace. -.TP -.B EPERM -The calling process is not privileged -(on Linux, does not have the necessary capability in its user namespace: -.B CAP_SETUID -in the case of -.BR setreuid (), -or -.B CAP_SETGID -in the case of -.BR setregid ()) -and a change other than (i) -swapping the effective user (group) ID with the real user (group) ID, -or (ii) setting one to the value of the other or (iii) setting the -effective user (group) ID to the value of the -saved set-user-ID (saved set-group-ID) was specified. -.SH VERSIONS -POSIX.1 does not specify all of the UID changes that Linux permits -for an unprivileged process. -For -.BR setreuid (), -the effective user ID can be made the same as the -real user ID or the saved set-user-ID, -and it is unspecified whether unprivileged processes may set the -real user ID to the real user ID, the effective user ID, or the -saved set-user-ID. -For -.BR setregid (), -the real group ID can be changed to the value of the saved set-group-ID, -and the effective group ID can be changed to the value of -the real group ID or the saved set-group-ID. -The precise details of what ID changes are permitted vary -across implementations. -.P -POSIX.1 makes no specification about the effect of these calls -on the saved set-user-ID and saved set-group-ID. -.SH STANDARDS -POSIX.1-2008. -.SH HISTORY -POSIX.1-2001, 4.3BSD (first appeared in 4.2BSD). -.P -Setting the effective user (group) ID to the -saved set-user-ID (saved set-group-ID) is -possible since Linux 1.1.37 (1.1.38). -.P -The original Linux -.BR setreuid () -and -.BR setregid () -system calls supported only 16-bit user and group IDs. -Subsequently, Linux 2.4 added -.BR setreuid32 () -and -.BR setregid32 (), -supporting 32-bit IDs. -The glibc -.BR setreuid () -and -.BR setregid () -wrapper functions transparently deal with the variations across kernel versions. -.\" -.SS C library/kernel differences -At the kernel level, user IDs and group IDs are a per-thread attribute. -However, POSIX requires that all threads in a process -share the same credentials. -The NPTL threading implementation handles the POSIX requirements by -providing wrapper functions for -the various system calls that change process UIDs and GIDs. -These wrapper functions (including those for -.BR setreuid () -and -.BR setregid ()) -employ a signal-based technique to ensure -that when one thread changes credentials, -all of the other threads in the process also change their credentials. -For details, see -.BR nptl (7). -.SH SEE ALSO -.BR getgid (2), -.BR getuid (2), -.BR seteuid (2), -.BR setgid (2), -.BR setresuid (2), -.BR setuid (2), -.BR capabilities (7), -.BR credentials (7), -.BR user_namespaces (7) |