Historically receive buffer overflows have been ignored and programs
could not tell if they missed messages or messages had been truncated
because of overflows. Since programs historically do not expect to get
receive overflow errors, this behavior is not the default.
This is really really important for programs that use route(4) to keep in sync
with the system. If we loose a message then we need to reload the full system
state, otherwise the behaviour from that point is undefined and can lead
to chasing bogus bug reports.
Previously, we would accept any kind of LIO_* opcode, including ones
that were intended for in-kernel use only like LIO_SYNC (which is not
defined in userland). The situation became more serious with
022ca2fc7f. After that revision, setting
aio_lio_opcode to LIO_WRITEV or LIO_READV would trigger an assertion.
Note that POSIX does not specify what should happen if aio_lio_opcode is
invalid.
MFC-with: 022ca2fc7f
Reviewed by: jhb, tmunro, 0mp
Differential Revision: <https://reviews.freebsd.org/D28078
Without wrapping, rtld services and malloc(3) are not guaranteed
to operate correctly in the forked child.
Reviewed by: markj
MFC after: 1 week
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D28088
aio_fsync(O_DSYNC, ...) is the asynchronous version of fdatasync(2).
Reviewed by: kib, asomers, jhb
Differential Review: https://reviews.freebsd.org/D25071
POSIX O_DSYNC means that writes include an implicit fdatasync(2), just
as O_SYNC implies fsync(2).
VOP_WRITE() functions that understand the new IO_DATASYNC flag can act
accordingly, but we'll still pass down IO_SYNC so that file systems that
don't understand it will continue to provide the stronger O_SYNC
behaviour.
Flag also applies to fcntl(2).
Reviewed by: kib, delphij
Differential Revision: https://reviews.freebsd.org/D25090
POSIX AIO is great, but it lacks vectored I/O functions. This commit
fixes that shortcoming by adding aio_writev and aio_readv. They aren't
part of the standard, but they're an obvious extension. They work just
like their synchronous equivalents pwritev and preadv.
It isn't yet possible to use vectored aiocbs with lio_listio, but that
could be added in the future.
Reviewed by: jhb, kib, bcr
Relnotes: yes
Differential Revision: https://reviews.freebsd.org/D27743
PR#252358 reported a serious performance problem w.r.t.
cp(1) when copying large non-sparse files.
This problem appears to have been caused by cp(1)
calling copy_file_range(2) with a small "len" argument.
This patch adds a recommendation to use a large "len"
value where possible, for performance reasons.
Reviewed by: asomers
Differential Revision: https://reviews.freebsd.org/D27935
- varios "new sentence, new line" warnings
- varios "sections out of conventional order" warnings
- varios "unusual Xr order" warnings
- varios "missing section argument" warnings
- varios "no blank before trailing delimiter" warnings
- varios "normalizing date format" warnings
MFC after: 1 month
Sort by manpage section, then sort entries alphabetically.
This makes the manpages `make manlint` clean.
MFC after: 1 week
Sponsored by: DellEMC Isilon
Months should be fully spelled as their local-specific equivalents: in this
case `Oct` should have been spelled like `October`.
Reported by: make manlint
MFC after: 1 week
Sponsored by: DellEMC Isilon
The CAVEATS section was misspelled as "CAVEAT" before this change. Fix the
spelling to identify issues related to the section.
Furthermore, given that the section order was incorrect, move the CAVEATS
section down to the bottom of the manpage, per the conventional section
order.
MFC after: 1 week
Reported by: make manlint
Sponsored by: DellEMC Isilon
This is being done for the formatting and context changes. While the net content
hasn't been changed, the content/context changes were sufficient to warrant the
date bump.
MFC after: 1 week
MFC with: r368431, r368433, r368434, r368435
Sponsored by: DellEMC Isilon
While some of the syscalls' behavior were documented and implied in the
RETURN VALUES section by earlier, e.g., the DESCRIPTION sections, as having
behavior of the other calls (`*_fd` vs `*_file` vs `*_link`), there was a lot
of implied return value behavior in the section prior to this change.
Explicitly document the syscall behavior per the current implementation in
sys/kern/vfs_extattr.c so others can better develop based on its explicit
documented behavior instead of having to digest the context of the manpage to
understand the appropriate behavior.
MFC after: 1 week
MFC with: r368431, r368433, r368434
Sponsored by: DellEMC Isilon
- Remove an unnecessary trailing comma separating a two-item clause.
- Sort more function calls alphabetically (in the same vein as r368433).
MFC after: 1 week
Sponsored by: DellEMC Isilon
Although some sections of the manpage sort the syscalls alphabetically, many
core areas of the manpage do not. Sort the syscalls so it is easier to pick out
functional changes and to improve manpage readability.
This formatting change is also being done to make future functional changes
easier to spot.
MFC after: 1 week
Sponsored by: DellEMC Isilon
The date with .Dd prior to this change isn't canonically spelled out: it
should have been "December", not "Dec".
MFC after: 1 week
Sponsored by: DellEMC Isilon
- The CAVEATS section was misspelled as "CAVEAT".
- The CAVEATS section should come before the "BUGS" section and after
other existing sections by convention.
MFC after: 1 week
Reported by: make manlint
Sponsored by: DellEMC Isilon
This clever technique to get a time remaining back was added to support sem_clockwait_np.
Reviewed by: kib, vangyzen
MFC after: 1 week
Differential Revision: https://reviews.freebsd.org/D27160
Foundation copyrights, approved by emaste@. It does not include
files which carry other people's copyrights; if you're one
of those people, feel free to make similar change.
Reviewed by: emaste, imp, gbe (manpages)
Differential Revision: https://reviews.freebsd.org/D26980
This also fixes a minor issue that was missed in the initial review; the
layout of the MFD_HUGE_* flags is actually not 1:1 bit:flag -- it instead
borrowed the Linux convention of how this is laid out since it was
originally implemented on Linux, the top 6 bits represent the shift required
for the requested page size.
This allows us to remove the flag <-> pgsize mapping table and simplify the
logic just prior to validation of the requested page size.
While we're here, fix two small nits:
- HUGETLB memfd shouldn't exhibit the SHM_GROW_ON_WRITE behavior. We can
only grow largepage shm by appropriately aligned (i.e. requested pagesize)
sizes, so it can't work in the typical/sane fashion. Furthermore, Linux
does the same, so let's be compatible.
- We don't allow MFD_HUGETLB without specifying a pagesize, so no need to
check for that later.
Reviewed by: kib (slightly earlier version)
Literally returning EINVAL from a function designed to return an fd makes
for interesting scenarios.
I cannot assign enough pointy hats to cover this one.
r365524 did accidentally invert this check that sets SHM_LARGEPAGE, leading
non-hugetlb memfd as unconfigured largepage shm and thus test failures when
we try to ftruncate or write to them.
PR: 249236
Discussed with: kib
largepage shm objects.
And since we can, add memfd_create(MFD_HUGETLB) support, hopefully
close enough to the Linux feature.
Reviewed by: markj
Tested by: pho
Sponsored by: The FreeBSD Foundation
MFC after: 1 week
Differential revision: https://reviews.freebsd.org/D24652
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
Currently we use a single bit to indicate whether the virtual page is
part of a superpage. To support a forthcoming implementation of
non-transparent 1GB superpages, it is useful to provide more detailed
information about large page sizes.
The change converts MINCORE_SUPER into a mask for MINCORE_PSIND(psind)
values, indicating a mapping of size psind, where psind is an index into
the pagesizes array returned by getpagesizes(3), which in turn comes
from the hw.pagesizes sysctl. MINCORE_PSIND(1) is equal to the old
value of MINCORE_SUPER.
For now, two bits are used to record the page size, permitting values
of MAXPAGESIZES up to 4.
Reviewed by: alc, kib
Sponsored by: Juniper Networks, Inc.
Sponsored by: Klara, Inc.
Differential Revision: https://reviews.freebsd.org/D26238
In certain situations lseek(2) will return successful although if no seek
was performed. This can happen when operating on devices that don't support
seeking (older tape drives) or when operating on changeable media devices
(such as DVD or Blu-ray devices) without a medium inserted.
Document this within the man page and update the POSIX compliance while here.
PR: 162765
Submitted by: arundel@
Reported by: arundel@
Reviewed by: bcr (mentor)
Approved by: bcr (mentor)
MFC after: 1 week
Differential Revision: https://reviews.freebsd.org/D25646
Some older references called it 'arg'
Also fix a syntax error that was underlining an entire sentence.
PR: 247386
Reported by: Paul Floyd <paulf@free.fr>, PauAmma (research)
MFC after: 2 weeks
Sponsored by: Klara Inc.
memfd_create fds will no longer require an ftruncate(2) to set the size;
they'll grow (to the extent that it's possible) upon write(2)-like syscalls.
Reviewed by: kib
Differential Revision: https://reviews.freebsd.org/D25502
While this behaviour is harmless, it is really just an artifact of the
fact that the msgctl(2) implementation uses a user-visible structure as
part of the internal implementation, so it is not deliberate and these
pointers are not useful to userspace. Thus, NULL them out before
copying out, and remove references to them from the manual page.
Reported by: Jeffball <jeffball@grimm-co.com>
Reviewed by: emaste, kib
MFC after: 1 week
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D25600
- Add STANDARDS and HISTORY sections within the appropriate manpages
- Mention two USENIX papers within kqueue(2) and strlcpy(3)
Reviewed by: bcr (mentor)
Approved by: bcr (mentor)
Obtained from: NetBSD
MFC after: 7 days
Differential Revision: https://reviews.freebsd.org/D24650
This commit adds the priv(9) that waters down the sysctl to make it only
allow read(2) of a dirfd by the system root. Jailed root is not allowed, but
jail policy and superuser policy will abstain from allowing/denying it so
that a MAC module can fully control the policy.
Such a MAC module has been written, and can be found at:
https://people.freebsd.org/~kevans/mac_read_dir-0.1.0.tar.gz
It is expected that the MAC module won't be needed by many, as most only
need to do such diagnostics that require this behavior as system root
anyways. Interested parties are welcome to grab the MAC module above and
create a port or locally integrate it, and with enough support it could see
introduction to base. As noted in mac_read_dir.c, it is released under the
BSD 2 clause license and allows the restrictions to be lifted for only
jailed root or for all unprivileged users.
PR: 246412
Reviewed by: mckusick, kib, emaste, jilles, cy, phk, imp (all previous)
Reviewed by: rgrimes (latest version)
Differential Revision: https://reviews.freebsd.org/D24596
Historically, we've allowed read() of a directory and some filesystems will
accommodate (e.g. ufs/ffs, msdosfs). From the history department staffed by
Warner: <<EOF
pdp-7 unix seemed to allow reading directories, but they were weird, special
things there so I'm unsure (my pdp-7 assembler sucks).
1st Edition's sources are lost, mostly. The kernel allows it. The
reconstructed sources from 2nd or 3rd edition read it though.
V6 to V7 changed the filesystem format, and should have been a warning, but
reading directories weren't materially changed.
4.1b BSD introduced readdir because of UFS. UFS broke all directory reading
programs in 1983. ls, du, find, etc all had to be rewritten. readdir() and
friends were introduced here.
SysVr3 picked up readdir() in 1987 for the AT&T fork of Unix. SysVr4 updated
all the directory reading programs in 1988 because different filesystem
types were introduced.
In the 90s, these interfaces became completely ubiquitous as PDP-11s running
V7 faded from view and all the folks that initially started on V7 upgraded
to SysV. Linux never supported this (though I've not done the software
archeology to check) because it has always had a pathological diversity of
filesystems.
EOF
Disallowing read(2) on a directory has the side-effect of masking
application bugs from relying on other implementation's behavior
(e.g. Linux) of rejecting these with EISDIR across the board, but allowing
it has been a vector for at least one stack disclosure bug in the past[0].
By POSIX, this is implementation-defined whether read() handles directories
or not. Popular implementations have chosen to reject them, and this seems
sensible: the data you're reading from a directory is not structured in some
unified way across filesystem implementations like with readdir(2), so it is
impossible for applications to portably rely on this.
With this patch, we will reject most read(2) of a dirfd with EISDIR. Users
that know what they're doing can conscientiously set
bsd.security.allow_read_dir=1 to allow read(2) of directories, as it has
proven useful for debugging or recovery. A future commit will further limit
the sysctl to allow only the system root to read(2) directories, to make it
at least relatively safe to leave on for longer periods of time.
While we're adding logic pertaining to directory vnodes to vn_io_fault, an
additional assertion has also been added to ensure that we're not reaching
vn_io_fault with any write request on a directory vnode. Such request would
be a logical error in the kernel, and must be debugged rather than allowing
it to potentially silently error out.
Commented out shell aliases have been placed in root's chsrc/shrc to promote
awareness that grep may become noisy after this change, depending on your
usage.
A tentative MFC plan has been put together to try and make it as trivial as
possible to identify issues and collect reports; note that this will be
strongly re-evaluated. Tentatively, I will MFC this knob with the default as
it is in HEAD to improve our odds of actually getting reports. The future
priv(9) to further restrict the sysctl WILL NOT BE MERGED BACK, so the knob
will be a faithful reversion on stable/12. We will go into the merge
acknowledging that the sysctl default may be flipped back to restore
historical behavior at *any* point if it's warranted.
[0] https://www.freebsd.org/security/advisories/FreeBSD-SA-19:10.ufs.asc
PR: 246412
Reviewed by: mckusick, kib, emaste, jilles, cy, phk, imp (all previous)
Reviewed by: rgrimes (latest version)
MFC after: 1 month (note the MFC plan mentioned above)
Relnotes: absolutely, but will amend previous RELNOTES entry
Differential Revision: https://reviews.freebsd.org/D24596
One of the error descriptions referred to permissions; in context the
meaning was probably clear, but the prot values are properly called
protections.
MFC after: 1 week
Sponsored by: The FreeBSD Foundation
functionality first appeared in FreeBSD.
Submitted by: Gordon Bergling gbergling_gmail.com
Approved by: bcr
Differential Revision: https://reviews.freebsd.org/D24677
sendto(2), sendmsg(2) and sendmmsg(2) return ENOTCONN if a destination
address is specified and the socket is not connected and the socket
protocol does not automatically connect ("implied connect"). Document
that. Also document the fact that the destination address is ignored
for connection-mode sockets if the socket is already connected.
PR: 245817
Submitted by: Erik Inge Bolsø <knan-bfo@modirum.com>
MFC after: 1 week
Differential Revision: https://reviews.freebsd.org/D24530
Contrary to the kevent man page, EV_EOF on a fifo is not cleared by
EV_CLEAR. Modify the read and write filters to clear EV_EOF when the
fifo's PIPE_EOF flag is clear, and update the man page to document the
new behaviour.
Modify the write filter to return the amount of buffer space available
even if no readers are present. This matches the behaviour for sockets.
When reading from a pipe, only call pipeselwakeup() if some data was
actually read. This prevents the continuous re-triggering of a
EVFILT_READ event on EOF when in edge-triggered mode.
PR: 203366, 224615
Submitted by: Jan Kokemüller <jan.kokemueller@gmail.com>
MFC after: 2 weeks
Differential Revision: https://reviews.freebsd.org/D24528
In r326576 ("use @@@ instead of @@ in __sym_default"), an earlier version of
the phabricator-discussed patch was inadvertently committed. The commit
message claims that @@@ means that weak is not needed, but that was due to a
misunderstanding of the use of weak symbols in this context by the submitted
in the first draft of the patch; the description text was not updated to
match the discussion. As discussed in phabricator, weak is needed for
symbol interposing because of the behavior of our rtld, and is widely used
elsewhere in libc.
This partial revert restores the approved version of the patch and permits
symbol interposing for openat.
Reported by: Raymond Ramsden <rramsden AT isilon.com>
Reviewed by: dim, emaste, kib (2017)
Discussed with: kib (2020)
Differential Revision: https://reviews.freebsd.org/D11653
In the below-referenced PR, a case is attached of a simple reproducer that
exhibits suboptimal behavior: EVFILT_READ and EVFILT_WRITE being set in the
same kevent(2) call will only honor the first one. This is, in-fact, how
it's supposed to work.
A read of the manpage leads me to believe we could be more clear about this;
right now there's a logical leap to make in the relevant statement: "When
passed as input, it forces EV_ERROR to always be returned." -- the logical
leap being that this indicates the caller should have allocated space for
the change to be returned with EV_ERROR indicated in the events, or
subsequent filters will get dropped on the floor.
Another possible workaround that accomplishes similar effect without needing
space for all events is just setting EV_RECEIPT on the final change being
passed in; if any errored before it, the kqueue would not be drained. If we
made it to the final change with EV_RECEIPT set, then we would return that
one with EV_ERROR and still not drain the kqueue. This would seem to not be
all that advisable.
PR: 229741
MFC after: 1 week
Include a temporarily compatibility shim as well for kernels predating
close_range, since closefrom is used in some critical areas.
Reviewed by: markj (previous version), kib
Differential Revision: https://reviews.freebsd.org/D24399
sonewconn() emits debug-level messages when a listen socket's queue
overflows. Currently, sonewconn() tracks overflows on a global basis. It
will only log one message every 60 seconds, regardless of how many sockets
experience overflows. And, when it next logs at the end of the 60 seconds,
it records a single message referencing a single PCB with the total number
of overflows across all sockets.
This commit changes to per-socket overflow tracking. The code will now
log one message every 60 seconds per socket. And, the code will provide
per-socket queue length and overflow counts. It also provides a way to
change the period between log messages using a sysctl.
Reviewed by: jhb (previous version), bcr (manpages)
MFC after: 2 weeks
Sponsored by: Netflix, Inc.
Differential Revision: https://reviews.freebsd.org/D24316
This had been introduced to ease any pain for using slightly older kernels
with a newer libc, e.g., for bisecting a kernel across the introduction of
shm_open2(2). 6 months has passed, retire the fallback and let shm_open()
unconditionally call shm_open2().
Stale includes are removed as well.
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
This is an application of the kernel overflow fix from r357948 to
userspace, based on the algorithm developed by Bruce Evans. To keep
the ABI of the vds_timekeep stable, instead of adding the large_delta
member, MSB of both multipliers are added to quickly estimate the overflow.
Sponsored by: The FreeBSD Foundation
MFC after: 2 weeks
While here, drop an extra conjunction from the list of error
conditions for the remaining EIO description in symlink(2).
Discussed with: mckusick (trimming duplicates)
MFC after: 2 weeks
EINTEGRITY was previously documented as a UFS-specific error for
mount(2). This documents EINTEGRITY as a filesystem-independent error
that may be reported by the backing store of a filesystem.
While here, document EIO as a filesystem-independent error for both
mount(2) and posix_fadvise(2). EIO was previously only documented for
UFS for mount(2).
Reviewed by: mckusick
Suggested by: mckusick
MFC after: 2 weeks
Sponsored by: Chelsio Communications
Differential Revision: https://reviews.freebsd.org/D24168
when a superblock check-hash error is detected. This change clarifies
a mount that failed due to media hardware failures (EIO) from a mount
that failed due to media errors (EINTEGRITY) that can be corrected by
running fsck(8).
Sponsored by: Netflix
From POSIX,
[ENOTSUP]
The implementation does not support the combination of accesses
requested in the prot argument.
This fits the case that prot contains permissions which are not a subset
of prot_max.
Reviewed by: brooks, cem
Relnotes: Yes
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D23843
Also update comments for which architectures use 128 bit long doubles,
as appropriate.
The softfloat specialization routines weren't updated since they
appear to be from an upstream source which we may want to update in
the future to get a more favorable license.
Reviewed by: emaste@
Differential Revision: https://reviews.freebsd.org/D23658
Update the man page to mention that extending a file with truncate(2)
is required by POSIX as of 2008.
Reviewed by: bcr
MFC after: 2 weeks
Sponsored by: Dell EMC Isilon
Differential Revision: https://reviews.freebsd.org/D23354
A new syscall sigfastblock(2) is added which registers a uint32_t
variable as containing the count of blocks for signal delivery. Its
content is read by kernel on each syscall entry and on AST processing,
non-zero count of blocks is interpreted same as the signal mask
blocking all signals.
The biggest downside of the feature that I see is that memory
corruption that affects the registered fast sigblock location, would
cause quite strange application misbehavior. For instance, the process
would be immune to ^C (but killable by SIGKILL).
With consumers (rtld and libthr added), benchmarks do not show a
slow-down of the syscalls in micro-measurements, and macro benchmarks
like buildworld do not demonstrate a difference. Part of the reason is
that buildworld time is dominated by compiler, and clang already links
to libthr. On the other hand, small utilities typically used by shell
scripts have the total number of syscalls cut by half.
The syscall is not exported from the stable libc version namespace on
purpose. It is intended to be used only by our C runtime
implementation internals.
Tested by: pho
Disscussed with: cem, emaste, jilles
Sponsored by: The FreeBSD Foundation
Differential revision: https://reviews.freebsd.org/D12773
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
Prior to introduction of this op libc's readdir would call fstatfs(2), in
effect unnecessarily copying kilobytes of data just to check fs name and a
mount flag.
Reviewed by: kib (previous version)
Differential Revision: https://reviews.freebsd.org/D23162
Treat it as a synonym for GRND_NONBLOCK. The reasoning is this:
We have two choices for handling Linux's GRND_INSECURE API flag.
1. We could ignore it completely (like GRND_RANDOM). However, this might
produce the surprising result of GRND_INSECURE requests blocking, when the
Linux API does not block.
2. Alternatively, we could treat GRND_INSECURE requests as requests for
GRND_NONBLOCk. Here, the surprising result for Linux programs is that
invocations with unseeded random(4) will produce EAGAIN, rather than
garbage.
Honoring the flag in the way Linux does seems fraught. If we actually use
the output of a random(4) implementation prior to seeding, we leak some
entropy (in an information theory and also practical sense) from what will
be the initial seed to attackers (or allow attackers to arbitrary DoS
initial seeding, if we don't leak). This seems unacceptable -- it defeats
the purpose of blocking on initial seeding.
Secondary to that concern, before seeding we may have arbitrarily little
entropy collected; producing output from zero or a handful of entropy bits
does not seem particularly useful to userspace.
If userspace can accept garbage, insecure, non-random bytes, they can create
their own insecure garbage with srandom(time(NULL)) or similar. Any program
which would be satisfied with a 3-bit key CTR stream has no need for CSPRNG
bytes. So asking the kernel to produce such an output from the secure
getrandom(2) API seems inane.
For now, we've elected to emulate GRND_INSECURE as an alternative spelling
of GRND_NONBLOCK (2). Consider this API not-quite stable for now. We
guarantee it will never block. But we will attempt to monitor actual port
uptake of this bizarre API and may revise our plans for the unseeded
behavior (prior stable/13 branching).
Approved by: csprng(markm), manpages(bcr)
See also: https://lwn.net/ml/linux-kernel/cover.1577088521.git.luto@kernel.org/
See also: https://lwn.net/ml/linux-kernel/20200107204400.GH3619@mit.edu/
Differential Revision: https://reviews.freebsd.org/D23130
This opens the door for other descriptor types to implement
posix_fallocate(2) as needed.
Reviewed by: kib, bcr (manpages)
Differential Revision: https://reviews.freebsd.org/D23042
As mandated by POSIX. Also clarify the kill(2) manpage.
While there, restructure the code in killpg1() to use helper which
keeps overall state of the process list iteration in the killpg1_ctx
structued, later used to infer the error returned.
Reported by: amdmi3
Reviewed by: jilles
Sponsored by: The FreeBSD Foundation
MFC after: 2 weeks
Differential revision: https://reviews.freebsd.org/D22621
o Remove All Rights Reserved from my notices
o imp@FreeBSD.org everywhere
o regularize punctiation, eliminate date ranges
o Make sure that it's clear that I don't claim All Rights reserved by listing
All Rights Reserved on same line as other copyright holders (but not
me). Other such holders are also listed last where it's clear.
While FreeBSD's implementation of these expect an int inside of libc, that's an
implementation detail that we can hide from the user as it's the natural
promotion of the current mode_t type and before it is used in the kernel, it's
converted back to the narrower type that's the current definition of mode_t. As
such, documenting int is at best confusing and at worst misleading. Instead add
a note that these args are variadic and as such calling conventions may differ
from non-variadic arguments.
promoted to ints).
- `mode_t` is `uint16_t` (`sys/sys/_types.h`)
- `openat` takes variadic args
- variadic args cannot be 16-bit, and indeed the code uses int
- the manpage currently kinda implies the argument is 16-bit by saying `mode_t`
Prompted by Rust things: https://github.com/tailhook/openat/issues/21
Submitted by: Greg V at unrelenting
Differential Revision: https://reviews.freebsd.org/D21816
Add an atomic shm rename operation, similar in spirit to a file
rename. Atomically unlink an shm from a source path and link it to a
destination path. If an existing shm is linked at the destination
path, unlink it as part of the same atomic operation. The caller needs
the same permissions as shm_unlink to the shm being renamed, and the
same permissions for the shm at the destination which is being
unlinked, if it exists. If those fail, EACCES is returned, as with the
other shm_* syscalls.
truss support is included; audit support will come later.
This commit includes only the implementation; the sysent-generated
bits will come in a follow-on commit.
Submitted by: Matthew Bryan <matthew.bryan@isilon.com>
Reviewed by: jilles (earlier revision)
Reviewed by: brueffer (manpages, earlier revision)
Relnotes: yes
Sponsored by: Dell EMC Isilon
Differential Revision: https://reviews.freebsd.org/D21423
Described in [1], signal handlers running in a vfork child have
opportunities to corrupt the parent's state. Address this by adding a new
rfork(2) flag, RFSPAWN, that has vfork(2) semantics but also resets signal
handlers in the child during creation.
x86 uses rfork_thread(3) instead of a direct rfork(2) because rfork with
RFMEM/RFSPAWN cannot work when the return address is stored on the stack --
further information about this problem is described under RFMEM in the
rfork(2) man page.
Addressing this has been identified as a prerequisite to using posix_spawn
in subprocess on FreeBSD [2].
[1] https://ewontfix.com/7/
[2] https://bugs.python.org/issue35823
Reviewed by: jilles, kib
Differential Revision: https://reviews.freebsd.org/D19058
When RFSPAWN is passed, rfork exhibits vfork(2) semantics but also resets
signal handlers in the child during creation to avoid a point of corruption
of parent state from the child.
This flag will be used by posix_spawn(3) to handle potential signal issues.
Reviewed by: jilles, kib
Differential Revision: https://reviews.freebsd.org/D19058
memfd_create is effectively a SHM_ANON shm_open(2) mapping with optional
CLOEXEC and file sealing support. This is used by some mesa parts, some
linux libs, and qemu can also take advantage of it and uses the sealing to
prevent resizing the region.
This reimplements shm_open in terms of shm_open2(2) at the same time.
shm_open(2) will be moved to COMPAT12 shortly.
Reviewed by: markj, kib
Differential Revision: https://reviews.freebsd.org/D21393
The two options are
* nocover/cover: Prevent/allow mounting over an existing root mountpoint.
E.g., "mount -t ufs -o nocover /dev/sd1a /usr/local" will fail if /usr/local
is already a mountpoint.
* emptydir/noemptydir: Prevent/allow mounting on a non-empty directory.
E.g., "mount -t ufs -o emptydir /dev/sd1a /usr" will fail.
Neither of these options is intended to be a default, for historical and
compatibility reasons.
Reviewed by: allanjude, kib
Differential Revision: https://reviews.freebsd.org/D21458
When SO_TIMESTAMP is set, the kernel will attempt to attach a timestamp as
ancillary data to each IP datagram that is received on the socket. However,
it may fail, for example due to insufficient memory. In that case the
packet will still be received but not timestamp will be attached.
Reviewed by: kib
MFC after: 3 days
Differential Revision: https://reviews.freebsd.org/D21607
It allows a process to request that stack gap was not applied to its
stacks, retroactively. Also it is possible to control the gaps in the
process after exec.
PR: 239894
Reviewed by: alc
Sponsored by: The FreeBSD Foundation
Differential revision: https://reviews.freebsd.org/D21352
Previously userspace would issue one syscall to resolve the sysctl and then
another one to actually use it. Do it all in one trip.
Fallback is provided in case newer libc happens to be running on an older
kernel.
Submitted by: Pawel Biernacki
Reported by: kib, brooks
Differential Revision: https://reviews.freebsd.org/D17282
Although libc syscall wrappers do not get checked in this can aid in
finding the source of generated files when spelunking in the objdir.
Multiple tools use @generated to identify generated files (for example,
in a review Phabricator will by default hide diffs in generated files).
For consistency use the @generated tag in makesyscalls.sh as we've done
for other generated files, even though these wrappers aren't checked in
to the tree.
copy_file_range.2 is a new man page (content change).
Reviewed by: kib, asomers
Relnotes: yes
Differential Revision: https://reviews.freebsd.org/D20584
This ptrace operation returns a structure containing the error and
return values from the current system call. It is only valid when a
thread is stopped during a system call exit (PL_FLAG_SCX is set).
The sr_error member holds the error value from the system call. Note
that this error value is the native FreeBSD error value that has _not_
been translated to an ABI-specific error value similar to the values
logged to ktrace.
If sr_error is zero, then the return values of the system call will be
set in sr_retval[0] and sr_retval[1].
Reviewed by: kib
MFC after: 1 month
Sponsored by: DARPA
Differential Revision: https://reviews.freebsd.org/D20901
Take part of the text from POSIX 2018 edition and describe the
atomicity requirements for read and write syscalls. See p1003.1-2018,
Vol.2, 2.9.7 Threads interaction with Regular File Operations.
Reviewed by: asomers
Sponsored by: The FreeBSD Foundation
MFC after: 3 days
Differential revision: https://reviews.freebsd.org/D20867
feature bit.
In particular, allocate the bit to opt-out the image from implicit
PROTMAX enablement. Provide procctl(2) verbs to set and query
implicit PROTMAX handling. The knobs mimic the same per-image flag
and per-process controls for ASLR.
Reviewed by: emaste, markj (previous version)
Discussed with: brooks
Sponsored by: The FreeBSD Foundation
Differential revision: https://reviews.freebsd.org/D20795
In the case of mmap(), add a HISTORY section. Mention that mmap() and
mprotect()'s documentation predates an implementation. The
implementation first saw wide use in 4.3-Reno, but there seems to be no
easy way to express that in mdoc so stick with 4.4BSD.
Reviewed by: emaste
Requested by: cem
Sponsored by: DARPA, AFRL
Differential Revision: https://reviews.freebsd.org/D20713
A new macro PROT_MAX() alters a protection value so it can be OR'd with
a regular protection value to specify the maximum permissions. If
present, these flags specify the maximum permissions.
While these flags are non-portable, they can be used in portable code
with simple ifdefs to expand PROT_MAX() to 0.
This change allows (e.g.) a region that must be writable during run-time
linking or JIT code generation to be made permanently read+execute after
writes are complete. This complements W^X protections allowing more
precise control by the programmer.
This change alters mprotect argument checking and returns an error when
unhandled protection flags are set. This differs from POSIX (in that
POSIX only specifies an error), but is the documented behavior on Linux
and more closely matches historical mmap behavior.
In addition to explicit setting of the maximum permissions, an
experimental sysctl vm.imply_prot_max causes mmap to assume that the
initial permissions requested should be the maximum when the sysctl is
set to 1. PROT_NONE mappings are excluded from this for compatibility
with rtld and other consumers that use such mappings to reserve
address space before mapping contents into part of the reservation. A
final version this is expected to provide per-binary and per-process
opt-in/out options and this sysctl will go away in its current form.
As such it is undocumented.
Reviewed by: emaste, kib (prior version), markj
Additional suggestions from: alc
Obtained from: CheriBSD
Sponsored by: DARPA, AFRL
Differential Revision: https://reviews.freebsd.org/D18880
The man page claims that with O_FSYNC (aka O_SYNC) the kernel will not cache
written data. However, that's not true. Nor does POSIX require it.
Perhaps it was true when that section of the man page was written in r69336
(I haven't checked). But it's not true now. Now the effect is simply that
writes are sent to disk immediately and synchronously, but they're still
cached.
See also: https://pubs.opengroup.org/onlinepubs/9699919799/
See also: ffs_write in sys/ufs/ffs/ffs_vnops.c
Reviewed by: cem
MFC after: 2 weeks
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D20641
Historically we have not distinguished between kernel wirings and user
wirings for accounting purposes. User wirings (via mlock(2)) were
subject to a global limit on the number of wired pages, so if large
swaths of physical memory were wired by the kernel, as happens with
the ZFS ARC among other things, the limit could be exceeded, causing
user wirings to fail.
The change adds a new counter, v_user_wire_count, which counts the
number of virtual pages wired by user processes via mlock(2) and
mlockall(2). Only user-wired pages are subject to the system-wide
limit which helps provide some safety against deadlocks. In
particular, while sources of kernel wirings typically support some
backpressure mechanism, there is no way to reclaim user-wired pages
shorting of killing the wiring process. The limit is exported as
vm.max_user_wired, renamed from vm.max_wired, and changed from u_int
to u_long.
The choice to count virtual user-wired pages rather than physical
pages was done for simplicity. There are mechanisms that can cause
user-wired mappings to be destroyed while maintaining a wiring of
the backing physical page; these make it difficult to accurately
track user wirings at the physical page layer.
The change also closes some holes which allowed user wirings to succeed
even when they would cause the system limit to be exceeded. For
instance, mmap() may now fail with ENOMEM in a process that has called
mlockall(MCL_FUTURE) if the new mapping would cause the user wiring
limit to be exceeded.
Note that bhyve -S is subject to the user wiring limit, which defaults
to 1/3 of physical RAM. Users that wish to exceed the limit must tune
vm.max_user_wired.
Reviewed by: kib, ngie (mlock() test changes)
Tested by: pho (earlier version)
MFC after: 45 days
Sponsored by: Netflix
Differential Revision: https://reviews.freebsd.org/D19908
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
If dso uses initial exec TLS mode, rtld tries to allocate TLS in
static space. If there is no space left, the dlopen(3) fails. If space
if allocated, initial content from PT_TLS segment is distributed to
all threads' pcbs, which was missed and caused un-initialized TLS
segment for such dso after dlopen(3).
The mode is auto-detected either due to the relocation used, or if the
DF_STATIC_TLS dynamic flag is set. In the later case, the TLS segment
is tried to allocate earlier, which increases chance of the dlopen(3)
to succeed. LLD was recently fixed to properly emit the flag, ld.bdf
did it always.
Initial test by: dumbbell
Tested by: emaste (amd64), ian (arm)
Tested by: Gerald Aryeetey <aryeeteygerald_rogers.com> (arm64)
Sponsored by: The FreeBSD Foundation
MFC after: 2 weeks
Differential revision: https://reviews.freebsd.org/D19072
According to 0mp, macros are not expanded in the argument provided to
-width. Use plain identifiers for width specification.
Noted and reviewed by: 0mp
Sponsored by: The FreeBSD Foundation
MFC after: 3 days
Differential revision: https://reviews.freebsd.org/D19308
back to the lever before r343030. For 64-bit machines reduce it slightly,
too. Together with r343030 I bumped the limit up to the value we use at
Netflix to serve 100 Gbit/s of sendfile traffic, and it probably isn't a
good default.
Provide a loader tunable to change vnode pager pbufs count. Document it.
This is meant to clarify the fact that the system call will not fail
with -1/EFAULT, as one might expect, when reading the sendfile(2)
manpage today.
While here, pet the mandoc linter, when dealing with the section that
describes valid values for `flags`.
PR: 232210
MFC after: 2 weeks
Approved by: emaste (mentor)
Reviewed by: glebius, 0mp
Differential Revision: https://reviews.freebsd.org/D18949
An integrity check such as a check-hash or a cross-correlation failed.
The integrity error falls between EINVAL that identifies errors in
parameters to a system call and EIO that identifies errors with the
underlying storage media. EINTEGRITY is typically raised by intermediate
kernel layers such as a filesystem or an in-kernel GEOM subsystem when
they detect inconsistencies. Uses include allowing the mount(8) command
to return a different exit value to automate the running of fsck(8)
during a system boot.
These changes make no use of the new error, they just add it. Later
commits will be made for the use of the new error number and it will
be added to additional manual pages as appropriate.
Reviewed by: gnn, dim, brueffer, imp
Discussed with: kib, cem, emaste, ed, jilles
Differential Revision: https://reviews.freebsd.org/D18765
Based on the description in Linux man page.
Reviewed by: markj, ngie (previous version)
Sponsored by: Mellanox Technologies
MFC after: 1 week
Differential revision: https://reviews.freebsd.org/D18837
from the local mapping.
Enable the setting by default.
The article behind the change: https://arxiv.org/abs/1901.01161
Reviewed by: markj
Discussed with: emaste
Sponsored by: The FreeBSD Foundation
MFC after: 1 week
Differential revision: https://reviews.freebsd.org/D18764
As it does for recv*(2), MSG_DONTWAIT indicates that the call should
not block, returning EAGAIN instead. Linux and OpenBSD both implement
this, so the change makes porting easier, especially since we do not
return EINVAL or so when unrecognized flags are specified.
Submitted by: Greg V <greg@unrelenting.technology>
Reviewed by: tuexen
MFC after: 1 week
Differential Revision: https://reviews.freebsd.org/D18728
There is no reason for it to behave differently from openat(fd, NULL).
Also the handling did not worked because the substituted path was from
the system address space, causing EFAULT.
Submitted by: Jack Halford <jack@gandi.net>
MFC after: 1 week
Differential revision: https://reviews.freebsd.org/D18501
The list of syscalls that modify st_atim, st_mtim, and st_ctim was quite out
of date and probably not accurate to begin with. Update it, and make it
clear that the list is open-ended.
Reviewed by: kib
MFC after: 2 weeks
Differential Revision: https://reviews.freebsd.org/D18410
The d_off field has been added to the dirent structure recently.
Currently filesystems don't support this feature. Support has been
added and tested for zfs, ufs, ext2fs, fdescfs, msdosfs and unionfs.
A stub implementation is available for cd9660, nandfs, udf and
pseudofs but hasn't been tested.
Motivation for this feature: our usecase is for a userspace nfs server
(nfs-ganesha) with zfs. At the moment we cache direntry offsets by
calling lseek once per entry, with this patch we can get the offset
directly from getdirentries(2) calls which provides a significant
speedup.
Submitted by: Jack Halford <jack@gandi.net>
Reviewed by: mckusick, pfg, rmacklem (previous versions)
Sponsored by: Gandi.net
MFC after: 1 week
Differential revision: https://reviews.freebsd.org/D17917
paths.
It was decided that committing the code and drafting of the man page
update is better than allowing the code to rot until wordsmithing
happens.
Reviewed by: jilles (previous version)
Discussed with: brooks, jilles, emaste
Sponsored by: The FreeBSD Foundation
MFC after: 1 week
Differential revision: https://reviews.freebsd.org/D17714
The comment isn't stale. The check is bogus in the sense that poll(2)
does not require pollfd entries to be unique in fd space, so there is no
reason there cannot be more pollfd entries than open or even allowed
fds. The check is mostly a seatbelt against accidental misuse or
abuse. FD_SETSIZE, while usually unrelated to poll, is used as an
arbitrary floor for systems with very low kern.maxfilesperproc.
Additionally, document this possible EINVAL condition in the poll.2
manual.
No functional change.
Reviewed by: markj
Sponsored by: Dell EMC Isilon
Differential Revision: https://reviews.freebsd.org/D17671
timezone offset. These values are generally zero.
While one still theoreticall could set these values, that's almost
never done. Users wishing to have an offset between the time of day
clock hardware and UTC use adjkerntz(8) instead.
localtime(3) should be used to find these values for the current
timezone.
Flags prevent open(2) and *at(2) vfs syscalls name lookup from
escaping the starting directory. Supposedly the interface is similar
to the same proposed Linux flags.
Reviewed by: jilles (code, previous version of manpages), 0mp (manpages)
Discussed with: allanjude, emaste, jonathan
Sponsored by: The FreeBSD Foundation
Differential revision: https://reviews.freebsd.org/D17547
There are multiple ways to wait for any child process to return a
status (e.g., waitpid(-1, ...), waitid(P_ALL, ...)), so don't be so
specific.
MFC after: 1 week
Sponsored by: The FreeBSD Foundation
the domain of a socket.
This is helpful when testing and Solaris and Linux have the same
socket option using the same name.
Reviewed by: bcr@, rrs@
Sponsored by: Netflix, Inc.
Differential Revision: https://reviews.freebsd.org/D16791
jails since FreeBSD 7.
Along with the system call, put the various security.jail.allow_foo and
security.jail.foo_allowed sysctls partly under COMPAT_FREEBSD11 (or
BURN_BRIDGES). These sysctls had two disparate uses: on the system side,
they were global permissions for jails created via jail(2) which lacked
fine-grained permission controls; inside a jail, they're read-only
descriptions of what the current jail is allowed to do. The first use
is obsolete along with jail(2), but keep them for the second-read-only use.
Differential Revision: D14791
Contrary to the removed comment, the kernel does appear to use the timezone
argument of settimeofday. The comment dates to the BSD4.4 import; I assume it
is just stale.
If a timer is updated (re-added) with a different time period
(specified in the .data field of the kevent), the new time period has
no effect; the timer will not expire until the original time has
elapsed. This violates the documented behavior as the kqueue(2) man
page says (in part) "Re-adding an existing event will modify the
parameters of the original event, and not result in a duplicate
entry."
This modification, adapted from a patch submitted by cem@ to PR214987,
fixes the kqueue system to allow updating a timer entry. The
kevent timer behavior is changed to:
* When a timer is re-added, update the timer parameters to and
re-start the timer using the new parameters.
* Allow updating both active and already expired timers.
* When the timer has already expired, dequeue any undelivered events
and clear the count of expirations.
All of these changes address the original PR and also bring the
FreeBSD and macOS kevent timer behaviors into agreement.
A few other changes were made along the way:
* Update the kqueue(2) man page to reflect the new timer behavior.
* Fix man page style issues in kqueue(2) diagnosed by igor.
* Update the timer libkqueue system test to test for the updated
timer behavior.
* Fix the (test) libkqueue common.h file so that it includes
config.h which defines various HAVE_* feature defines, before the
#if tests for such variables in common.h. This enables the use of
the actual err(3) family of functions.
* Fix the usages of the err(3) functions in the tests for incorrect
type of variables. Those were formerly undiagnosed due to the
disablement of the err(3) functions (see previous bullet point).
PR: 214987
Reported by: Brian Wellington <bwelling@xbill.org>
Reviewed by: kib
MFC after: 1 week
Relnotes: yes
Sponsored by: Dell EMC
Differential Revision: https://reviews.freebsd.org/D15778
Remove numactl(1), edit numa(4) to bring it some closer to reality,
provide libc ABI shims for old NUMA syscalls.
Noted and reviewed by: brooks (previous version)
Sponsored by: The FreeBSD Foundation
Differential revision: https://reviews.freebsd.org/D16142
No valid FreeBSD binary very called them (they would call lchown and
msync directly) and we haven't supported NetBSD binaries in ages.
This is a respin of r335983 with a workaround for the ancient BFD linker
in the libc stubs.
Reviewed by: kib
Sponsored by: DARPA, AFRL
Differential Revision: https://reviews.freebsd.org/D16193
RB_ASKNAME is no longer instructions to the boot loader to request a
prompt for which kernel to boot. Instead, it asks for what the root
file system to use. RB_INITNAME is unused, and never has been in
FreeBSD as far as I can tell. Remove it from the documentation and fix
comment. RB_SELFTEST and RB_MINIROOT likewise (though they were
completely undocumented). These last three constants can likely just
be deleted as nothing references them (even to set useless bits).
RB_ASKNAME doesn't actually survive reboot, however, so needs to be
communicated to the bootloader via other means. If the bootloader sets
it, though, it will be honored.
No valid FreeBSD binary ever called them (they would call lchown and
msync directly) and we haven't supported NetBSD binaries in ages.
Reviewed by: kib
Sponsored by: DARPA, AFRL
Differential Revision: https://reviews.freebsd.org/D15814
Add vertical space between struct definition and function prototype.
Use "NULL" to describe zero pointers, instead of "zero."
Remove perhaps unclear "can not" and replace. Tag struct member names used
with appropriate tags.
This patch adds a new socket option, SO_REUSEPORT_LB, which allow multiple
programs or threads to bind to the same port and incoming connections will be
load balanced using a hash function.
Most of the code was copied from a similar patch for DragonflyBSD.
However, in DragonflyBSD, load balancing is a global on/off setting and can not
be set per socket. This patch allows for simultaneous use of both the current
SO_REUSEPORT and the new SO_REUSEPORT_LB options on the same system.
Required changes to structures:
Globally change so_options from 16 to 32 bit value to allow for more options.
Add hashtable in pcbinfo to hold all SO_REUSEPORT_LB sockets.
Limitations:
As DragonflyBSD, a load balance group is limited to 256 pcbs (256 programs or
threads sharing the same socket).
This is a substantially different contribution as compared to its original
incarnation at svn r332894 and reverted at svn r332967. Thanks to rwatson@
for the substantive feedback that is included in this commit.
Submitted by: Johannes Lundberg <johalun0@gmail.com>
Obtained from: DragonflyBSD
Relnotes: Yes
Sponsored by: Limelight Networks
Differential Revision: https://reviews.freebsd.org/D11003
Previously, libc.so would initialize its notion of the break address
using _end, a special symbol emitted by the static linker following
the bss section. Compatibility issues between lld and ld.bfd could
cause the wrong definition of _end (libc.so's definition rather than
that of the executable) to be used, breaking the brk()/sbrk()
interface.
Avoid this problem and future interoperability issues by simply not
relying on _end. Instead, modify the break() system call to return
the kernel's view of the current break address, and have libc
initialize its state using an extra syscall upon the first use of the
interface. As a side effect, this appears to fix brk()/sbrk() usage
in executables run with rtld direct exec, since the kernel and libc.so
no longer maintain separate views of the process' break address.
PR: 228574
Reviewed by: kib (previous version)
MFC after: 2 months
Differential Revision: https://reviews.freebsd.org/D15663
Summary:
Added ptrace support for getting/setting the remaining part of the VSX registers
(the part that's not already covered by FPR or VR registers).
This is necessary to add support for VSX registers in debuggers.
Submitted by: Luis Pires
Differential Revision: https://reviews.freebsd.org/D15458
Super pages are supported on non-x86 architectures, so just remove the
incorrect note. While here, change terminology to be consistent with
mmap.2.
MFC after: 1 week
The vadvise syscall (aka ovadvise) is undocumented and has always been
implmented as returning EINVAL. Put the syscall under COMPAT11 and
provide a userspace implementation.
Reviewed by: kib
Sponsored by: DARPA, AFRL
Differential Revision: https://reviews.freebsd.org/D15557
More firmly suggest mmap(2) instead.
Include the history of arm64 and riscv shipping without brk/sbrk.
Mention that sbrk(0) produces unreliable results.
Reviewed by: emaste, Marcin Cieślak
MFC after: 3 days
Sponsored by: DARPA, AFRL
Differential Revision: https://reviews.freebsd.org/D15535
Each TCP connection that uses the system default cc_newreno(4) congestion
control algorithm module leaks a "struct newreno" (8 bytes of memory) at
connection initialisation time. The NULL-pointer dereference is only germane
when using the ABE feature, which is disabled by default.
While at it:
- Defer the allocation of memory until it is actually needed given that ABE is
optional and disabled by default.
- Document the ENOMEM errno in getsockopt(2)/setsockopt(2).
- Document ENOMEM and ENOBUFS in tcp(4) as being synonymous given that they are
used interchangeably throughout the code.
- Fix a few other nits also accidentally omitted from the original patch.
Reported by: Harsh Jain on freebsd-net@
Tested by: tjh@
Differential Revision: https://reviews.freebsd.org/D15358
Discovered during investigation into the PR - the description of
AT_FDCWD was somewhat confusing.
PR: 222632
Submitted by: Jan Kokemüller <jan.kokemueller@gmail.com>
MFC after: 1 week
-> PROC_PDEATHSIG_STATUS for consistency with other procctl(2)
operations names.
Requested by: emaste
Sponsored by: The FreeBSD Foundation
MFC after: 13 days
Allow processes to request the delivery of a signal upon death of
their parent process. Supposed consumer of the feature is PostgreSQL.
Submitted by: Thomas Munro
Reviewed by: jilles, mjg
MFC after: 2 weeks
Differential revision: https://reviews.freebsd.org/D15106
On older kernels, when userspace program disables SIGSYS, catch ENOSYS and
emulate getrandom(2) syscall with the kern.arandom sysctl (via existing
arc4_sysctl wrapper).
Special care is taken to faithfully emulate EFAULT on NULL pointers, because
sysctl(3) as used by kern.arandom ignores NULL oldp. (This was caught by
getentropy(3) ATF tests.)
Reported by: kib
Reviewed by: kib
Discussed with: delphij
Sponsored by: Dell EMC Isilon
Differential Revision: https://reviews.freebsd.org/D14785
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
POSIX defines no macros for these permissions.
Also remove unneeded headers from synopsis.
PR: 225905
Reviewed by: wblock
MFC after: 1 week
Differential Revision: https://reviews.freebsd.org/D14461
POSIX explicitly states that the application must declare union semun.
This makes no sense, but it is what it is. This brings us into line
with Linux, MacOS/Darwin, and NetBSD.
In a ports exp-run a moderate number of ports fail due to a lack of
approprate autotools-like discovery mechanisms or local patches. A
commit to address them will follow shortly.
PR: 224300, 224443 (exp-run)
Reviewed by: emaste, jhb, kib
Exp-run by: antoine
Sponsored by: DARPA, AFRL
Differential Revision: https://reviews.freebsd.org/D14492
This deliberately breaks the API in preperation for future syscall
revisions which will remove these nonstandard members.
In an exp-run a single port (devel/qemu-user-static) was found to
use them which it did becuase it emulates system calls. This has
been fixed in the ports tree.
PR: 224443 (exp-run)
Reviewed by: kib, jhb (previous version)
Exp-run by: antoine
Sponsored by: DARPA, AFRP
Differential Revision: https://reviews.freebsd.org/D14490