Files
freebsd/lib/libc/include/compat.h
T
Kyle Evans 9da2fe96ff kern: fix setgroups(2) and getgroups(2) to match other platforms
On most other platforms observed, including OpenBSD, NetBSD, and Linux,
these system calls have long since been converted to only touching the
supplementary groups of the process.  This poses both portability and
security concerns in porting software to and from FreeBSD, as this
subtle difference is a landmine waiting to happen.  Bugs have been
discovered even in FreeBSD-local sources, since this behavior is
somewhat unintuitive (see, e.g., fix 48fd05999b for chroot(8)).

Now that the egid is tracked outside of cr_groups in our ucred, convert
the syscalls to deal with only supplementary groups.  Some remaining
stragglers in base that had baked in assumptions about these syscalls
are fixed in the process to avoid heartburn in conversion.

For relnotes: application developers should audit their use of both
setgroups(2) and getgroups(2) for signs that they had assumed the
previous FreeBSD behavior of using the first element for the egid.  Any
calls to setgroups() to clear groups that used a single array of the
now or soon-to-be egid can be converted to setgroups(0, NULL) calls to
clear the supplementary groups entirely on all FreeBSD versions.

Co-authored-by:	olce (but bugs are likely mine)
Relnotes:	yes (see last paragraph)
Reviewed by:	kib
Differential Revision:	https://reviews.freebsd.org/D51648
2025-08-14 23:06:09 -05:00

84 lines
3.0 KiB
C

/*-
* SPDX-License-Identifier: BSD-2-Clause
*
* Copyright (c) 2009 Hudson River Trading LLC
* Written by: John H. Baldwin <[email protected]>
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
/*
* This file defines compatibility symbol versions for old system calls. It
* is included in all generated system call files.
*/
#ifndef __LIBC_COMPAT_H__
#define __LIBC_COMPAT_H__
#define __sym_compat(sym, impl, verid) \
.symver impl, sym@verid
#ifndef NO_COMPAT7
__sym_compat(__semctl, freebsd7___semctl, FBSD_1.0);
__sym_compat(msgctl, freebsd7_msgctl, FBSD_1.0);
__sym_compat(shmctl, freebsd7_shmctl, FBSD_1.0);
#endif
__sym_compat(nfstat, freebsd11_nfstat, FBSD_1.0);
__sym_compat(nlstat, freebsd11_nlstat, FBSD_1.0);
__sym_compat(nstat, freebsd11_nstat, FBSD_1.0);
__sym_compat(fhstat, freebsd11_fhstat, FBSD_1.0);
__sym_compat(fstat, freebsd11_fstat, FBSD_1.0);
__sym_compat(fstatat, freebsd11_fstatat, FBSD_1.1);
__sym_compat(lstat, freebsd11_lstat, FBSD_1.0);
__sym_compat(stat, freebsd11_stat, FBSD_1.0);
__sym_compat(getdents, freebsd11_getdents, FBSD_1.0);
__sym_compat(getdirentries, freebsd11_getdirentries, FBSD_1.0);
__sym_compat(getfsstat, freebsd11_getfsstat, FBSD_1.0);
__sym_compat(fhstatfs, freebsd11_fhstatfs, FBSD_1.0);
__sym_compat(fstatfs, freebsd11_fstatfs, FBSD_1.0);
__sym_compat(statfs, freebsd11_statfs, FBSD_1.0);
__sym_compat(mknod, freebsd11_mknod, FBSD_1.0);
__sym_compat(mknodat, freebsd11_mknodat, FBSD_1.1);
__sym_compat(kevent, freebsd11_kevent, FBSD_1.0);
__sym_compat(swapoff, freebsd13_swapoff, FBSD_1.0);
__sym_compat(getgroups, freebsd14_getgroups, FBSD_1.0);
__sym_compat(setgroups, freebsd14_setgroups, FBSD_1.0);
#undef __sym_compat
#define __weak_reference(sym,alias) \
.weak alias;.equ alias,sym
#undef __weak_reference
#endif /* __LIBC_COMPAT_H__ */