O_SEARCH is defined by POSIX [0] to open a directory for searching, skipping permissions checks on the directory itself after the initial open(). This is close to the semantics we've historically applied for O_EXEC on a directory, which is UB according to POSIX. Conveniently, O_SEARCH on a file is also explicitly undefined behavior according to POSIX, so O_EXEC would be a fine choice. The spec goes on to state that O_SEARCH and O_EXEC need not be distinct values, but they're not defined to be the same value. This was pointed out as an incompatibility with other systems that had made its way into libarchive, which had assumed that O_EXEC was an alias for O_SEARCH. This defines compatibility O_SEARCH/FSEARCH (equivalent to O_EXEC and FEXEC respectively) and expands our UB for O_EXEC on a directory. O_EXEC on a directory is checked in vn_open_vnode already, so for completeness we add a NOEXECCHECK when O_SEARCH has been specified on the top-level fd and do not re-check that when descending in namei. [0] https://pubs.opengroup.org/onlinepubs/9699919799/ Reviewed by: kib Differential Revision: https://reviews.freebsd.org/D23247 |
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bin | ||
cddl | ||
contrib | ||
crypto | ||
etc | ||
gnu | ||
include | ||
kerberos5 | ||
lib | ||
libexec | ||
release | ||
rescue | ||
sbin | ||
secure | ||
share | ||
stand | ||
sys | ||
targets | ||
tests | ||
tools | ||
usr.bin | ||
usr.sbin | ||
.arcconfig | ||
.arclint | ||
.cirrus.yml | ||
.clang-format | ||
.gitattributes | ||
.gitignore | ||
COPYRIGHT | ||
LOCKS | ||
MAINTAINERS | ||
Makefile | ||
Makefile.inc1 | ||
Makefile.libcompat | ||
Makefile.sys.inc | ||
ObsoleteFiles.inc | ||
README | ||
README.md | ||
RELNOTES | ||
UPDATING |
FreeBSD Source:
This is the top level of the FreeBSD source directory. This file
was last revised on:
FreeBSD
FreeBSD is an operating system used to power modern servers, desktops, and embedded platforms. A large community has continually developed it for more than thirty years. Its advanced networking, security, and storage features have made FreeBSD the platform of choice for many of the busiest web sites and most pervasive embedded networking and storage devices.
For copyright information, please see the file COPYRIGHT in this directory. Additional copyright information also exists for some sources in this tree - please see the specific source directories for more information.
The Makefile in this directory supports a number of targets for building components (or all) of the FreeBSD source tree. See build(7), config(8), https://www.freebsd.org/doc/en_US.ISO8859-1/books/handbook/makeworld.html, and https://www.freebsd.org/doc/en_US.ISO8859-1/books/handbook/kernelconfig.html for more information, including setting make(1) variables.
Source Roadmap:
bin System/user commands.
cddl Various commands and libraries under the Common Development
and Distribution License.
contrib Packages contributed by 3rd parties.
crypto Cryptography stuff (see crypto/README).
etc Template files for /etc.
gnu Various commands and libraries under the GNU Public License.
Please see gnu/COPYING* for more information.
include System include files.
kerberos5 Kerberos5 (Heimdal) package.
lib System libraries.
libexec System daemons.
release Release building Makefile & associated tools.
rescue Build system for statically linked /rescue utilities.
sbin System commands.
secure Cryptographic libraries and commands.
share Shared resources.
stand Boot loader sources.
sys Kernel sources.
sys/<arch>/conf Kernel configuration files. GENERIC is the configuration
used in release builds. NOTES contains documentation of
all possible entries.
tests Regression tests which can be run by Kyua. See tests/README
for additional information.
tools Utilities for regression testing and miscellaneous tasks.
usr.bin User commands.
usr.sbin System administration commands.
For information on synchronizing your source tree with one or more of the FreeBSD Project's development branches, please see:
https://www.freebsd.org/doc/en_US.ISO8859-1/books/handbook/current-stable.html