Current POSIX standard requires fork() to be async-signal safe. Neither
our implementation, nor implementations in other operating systems are,
and practically it is impossible to make fork() async-signal safe without
too much efforts. Also, that would put undue requirement that all atfork
handlers should be async-signal safe as well, which contradicts its main
use.
As result, Austin Group dropped the requirement, and added a new function
_Fork() that should be async-signal safe, but it does not call atfork
handlers. Basically, _Fork() can be implemented as a raw syscall.
Release of glibc 2.34 added _Fork(), do the same for FreeBSD.
Clarify threading behavior for fork() in the manpage.
Reviewed by: markj
Sponsored by: The FreeBSD Foundation
MFC after: 2 weeks
Differential revision: https://reviews.freebsd.org/D31378
getlogin_r is specified by POSIX to to take a size_t len, not int. Fix our
version to do the same, bump the symbol version due to ABI change and
provide compat.
This was reported to break compilation of Ruby 2.8.
Some discussion about the necessity of the ABI compat did take place in the
review. While many 64-bit platforms would likely be passing it in a 64-bit
register and zero-extended and thus, not notice ABI breakage, some do
sign-extend (e.g. mips).
PR: 247102
Submitted by: Bertram Scharpf <software@bertram-scharpf.de> (original)
Submitted by: cem (ABI compat)
MFC after: 1 week
Differential Revision: https://reviews.freebsd.org/D26335
close_range(min, max, flags) allows for a range of descriptors to be
closed. The Python folk have indicated that they would much prefer this
interface to closefrom(2), as the case may be that they/someone have special
fds dup'd to higher in the range and they can't necessarily closefrom(min)
because they don't want to hit the upper range, but relocating them to lower
isn't necessarily feasible.
sys_closefrom has been rewritten to use kern_close_range() using ~0U to
indicate closing to the end of the range. This was chosen rather than
requiring callers of kern_close_range() to hold FILEDESC_SLOCK across the
call to kern_close_range for simplicity.
The flags argument of close_range(2) is currently unused, so any flags set
is currently EINVAL. It was added to the interface in Linux so that future
flags could be added for, e.g., "halt on first error" and things of this
nature.
This patch is based on a syscall of the same design that is expected to be
merged into Linux.
Reviewed by: kib, markj, vangyzen (all slightly earlier revisions)
Differential Revision: https://reviews.freebsd.org/D21627
copy_file_range(2) is a Linux compatible syscall created by r350315.
Reviewed by: kib, asomers
Relnotes: yes
Differential Revision: https://reviews.freebsd.org/D20584
the file associated with the given file descriptor.
Reviewed by: kib, asomers
Reviewed by: cem, jilles, brooks (they reviewed previous version)
Discussed with: pjd, and many others
Differential Revision: https://reviews.freebsd.org/D14567
The general idea here is to provide userspace programs with well-defined
sources of entropy, in a fashion that doesn't require opening a new file
descriptor (ulimits) or accessing paths (/dev/urandom may be restricted
by chroot or capsicum).
getrandom(2) is the more general API, and comes from the Linux world.
Since our urandom and random devices are identical, the GRND_RANDOM flag
is ignored.
getentropy(3) is added as a compatibility shim for the OpenBSD API.
truss(1) support is included.
Tests for both system calls are provided. Coverage is believed to be at
least as comprehensive as LTP getrandom(2) test coverage. Additionally,
instructions for running the LTP tests directly against FreeBSD are provided
in the "Test Plan" section of the Differential revision linked below. (They
pass, of course.)
PR: 194204
Reported by: David CARLIER <david.carlier AT hardenedbsd.org>
Discussed with: cperciva, delphij, jhb, markj
Relnotes: maybe
Differential Revision: https://reviews.freebsd.org/D14500
Mainly focus on files that use BSD 3-Clause license.
The Software Package Data Exchange (SPDX) group provides a specification
to make it easier for automated tools to detect and summarize well known
opensource licenses. We are gradually adopting the specification, noting
that the tags are considered only advisory and do not, in any way,
superceed or replace the license texts.
Special thanks to Wind River for providing access to "The Duke of
Highlander" tool: an older (2014) run over FreeBSD tree was useful as a
starting point.
The setkey() and encrypt() functions are part of XSI, not the POSIX base
definitions. There is no strict requirement for us to provide these,
especially if we're only going to keep these around as undocumented
stubs. The same holds for des_setkey() and des_cipher().
Instead of providing functions that only generate warnings when linking,
simply disallow linking against them. The impact of this is relatively
low. It only causes two leaf ports to break. I'll see what I can do to
help out to get those fixed.
PR: 211626
The syscall is a trivial wrapper around new VOP_FDATASYNC(), sharing
code with fsync(2). For all filesystems, this commit provides the
implementation which delegates the work of VOP_FDATASYNC() to
VOP_FSYNC(). This is functionally correct but not efficient.
This is not yet POSIX-compliant implementation, because it does not
ensure that queued AIO requests are completed before returning.
Reviewed by: mckusick
Discussed with: avg (ZFS), jhb (AIO part)
Tested by: pho
Sponsored by: The FreeBSD Foundation
MFC after: 2 weeks
Differential revision: https://reviews.freebsd.org/D7471
glibc has a pretty nice function called crypt_r(3), which is nothing
more than crypt(3), but thread-safe. It accomplishes this by introducing
a 'struct crypt_data' structure that contains a buffer that is large
enough to hold the resulting string.
Let's go ahead and also add this function. It would be a shame if a
useful function like this wouldn't be usable in multithreaded apps.
Refactor crypt.c and all of the backends to no longer declare static
arrays, but write their output in a provided buffer.
There is no need to do any buffer length computation here, as we'll just
need to ensure that 'struct crypt_data' is large enough, which it is.
_PASSWORD_LEN is defined to 128 bytes, but in this case I'm picking 256,
as this is going to be part of the actual ABI.
Differential Revision: https://reviews.freebsd.org/D7306
breaking the ABI. Special value is stored in the lock pointer to
indicate shared lock, and offline page in the shared memory is
allocated to store the actual lock.
Reviewed by: vangyzen (previous version)
Discussed with: deischen, emaste, jhb, rwatson,
Martin Simmons <martin@lispworks.com>
Tested by: pho
Sponsored by: The FreeBSD Foundation
Start using the gcc sentinel attribute, which can be used to
mark varargs function that need a NULL pointer to mark argument
termination, like execl(3).
Relnotes: yes
or __POSIX_VISIBLE.
Whenever <sys/cdefs.h> sets __BSD_VISIBLE to non-zero, it also sets
__POSIX_VISIBLE and __XSI_VISIBLE to the newest version supported.
No functional change is intended.
I removed functionality not proposed for POSIX in Austin group issue #411.
A man page (my own) and test cases will follow in later commits.
PR: 176233
Submitted by: Jukka Ukkonen
The pipe2() function is similar to pipe() but allows setting FD_CLOEXEC and
O_NONBLOCK (on both sides) as part of the function.
If p points to two writable ints, pipe2(p, 0) is equivalent to pipe(p).
If the pointer is not valid, behaviour differs: pipe2() writes into the
array from the kernel like socketpair() does, while pipe() writes into the
array from an architecture-specific assembler wrapper.
Reviewed by: kan, kib
Add an API for alerting internal libc routines to the presence of
"unsafe" paths post-chroot, and use it in ftpd. [11:07]
Fix a buffer overflow in telnetd. [11:08]
Make pam_ssh ignore unpassphrased keys unless the "nullok" option is
specified. [11:09]
Add sanity checking of service names in pam_start. [11:10]
Approved by: so (cperciva)
Approved by: re (bz)
Security: FreeBSD-SA-11:06.bind
Security: FreeBSD-SA-11:07.chroot
Security: FreeBSD-SA-11:08.telnetd
Security: FreeBSD-SA-11:09.pam_ssh
Security: FreeBSD-SA-11:10.pam
it possible for the kernel to track login class the process is assigned to,
which is required for RCTL. This change also make setusercontext(3) call
setloginclass(2) and makes it possible to retrieve current login class using
id(1).
Reviewed by: kib (as part of a larger patch)
- Provide function prototype for nlm_syscall
- Don't assign a variable from the stack to a global var[1]
- Remove unused vars
Found by: clang static analyser [1]
Reviewed by: dfr
The ttyslot() function was originally part for SUSv1, marked LEGACY in
SUSv2 and removed later on. This function only makes sense when using
utmp(5), because it was used to determine the offset of the record for
the controlling TTY. It makes little sense to keep it here, because the
new utmpx file format doesn't index based on TTY slots.
if the new file mode is the same as it was before; however, this
optimization must be disabled for filesystems that support NFSv4 ACLs.
Chmod uses pathconf(2) to determine whether this is the case - however,
pathconf(2) always follows symbolic links, while the 'chmod -h' doesn't.
This change adds lpathconf(3) to make it possible to solve that problem
in a clean way.
Reviewed by: rwatson (earlier version)
Approved by: re (kib)
any open file descriptors >= 'lowfd'. It is largely identical to the same
function on other operating systems such as Solaris, DFly, NetBSD, and
OpenBSD. One difference from other *BSD is that this closefrom() does not
fail with any errors. In practice, while the manpages for NetBSD and
OpenBSD claim that they return EINTR, they ignore internal errors from
close() and never return EINTR. DFly does return EINTR, but for the common
use case (closing fd's prior to execve()), the caller really wants all
fd's closed and returning EINTR just forces callers to call closefrom() in
a loop until it stops failing.
Note that this implementation of closefrom(2) does not make any effort to
resolve userland races with open(2) in other threads. As such, it is not
multithread safe.
Submitted by: rwatson (initial version)
Reviewed by: rwatson
MFC after: 2 weeks
in the POSIX namespace, and hiding eaccess() and setproctitle().
Also move mknodat() from unistd.h to sys/stat.h where it belongs.
The *at() syscalls are only in CURRENT, so this shouldn't cause
problems.
*at, and fexecve to the POSIX.1-2008 namespace.
- Remove getwd, ualarm, usleep, and vfork from the XSI namespace.
- Remove mkdtemp from the POSIX.1-2008 namespace (should be in stdlib.h).
Adding exevpe() has caused some ports to break. Even though execvpe() is
a useful routine, it does not conform to any standards.
This patch is a little bit different from the patch sent to the mailing
list. I forgot to remove execvpe from the Symbol.map (which does not
seem to miscompile libc, though).
Reviewed by: davidxu
Approved by: philip
can be used as replacements for exec/fork in a lot of cases. This
change also added execvpe() which allows environment variable
PATH to be used for searching executable file, it is used for
implementing posix_spawnp().
PR: standards/122051
different from what has been offered in libc_r (the one spotted in the
original PR which is found in libthr has already been removed by David's
commit, which is rev. 1.44 of lib/libthr/thread/thr_private.h):
- Use POSIX standard prototype for ttyname_r, which is,
int ttyname_r(int, char *, size_t);
Instead of:
char *ttyname_r(int, char *, size_t);
This is to conform IEEE Std 1003.1, 2004 Edition [1].
- Since we need to use standard errno for return code, include
errno.h in ttyname.c
- Update ttyname(3) implementation according to reflect the API
change.
- Document new ttyname_r(3) behavior
- Since we already make use of a thread local storage for
ttyname(3), remove the BUGS section.
- Remove conflicting ttyname_r related declarations found in libc_r.
Hopefully this change should not have changed the API/ABI, as the ttyname_r
symbol was never introduced before the last unistd.h change which happens a
couple of days before.
[1] http://www.opengroup.org/onlinepubs/009695399/functions/ttyname.html
Requested by: Tom McLaughlin <tmclaugh sdf lonestar org>
Through PR: threads/76938
Patched by: Craig Rodrigues <rodrigc crodrigues org> (with minor changes)
Prompted by: mezz@
