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
realpath(3) is used a lot e.g., by clang and is a major source of getcwd
and fstatat calls. This can be done more efficiently in the kernel.
This works by performing a regular lookup while saving the name and found
parent directory. If the terminal vnode is a directory we can resolve it using
usual means. Otherwise we can use the name saved by lookup and resolve the
parent.
See the review for sample syscall counts.
Reviewed by: kib
Differential Revision: https://reviews.freebsd.org/D23574
-Werror warnings from clang 10.0.0, such as:
lib/libc/quad/fixdfdi.c:57:12: error: implicit conversion from 'long long' to 'double' changes value from 9223372036854775807 to 9223372036854775808 [-Werror,-Wimplicit-int-float-conversion]
if (x >= QUAD_MAX)
~~ ^~~~~~~~
/usr/obj/usr/src/powerpc.powerpc/tmp/usr/include/sys/limits.h:89:19: note: expanded from macro 'QUAD_MAX'
#define QUAD_MAX (__QUAD_MAX) /* max value for a quad_t */
^~~~~~~~~~
/usr/obj/usr/src/powerpc.powerpc/tmp/usr/include/machine/_limits.h:91:20: note: expanded from macro '__QUAD_MAX'
#define __QUAD_MAX __LLONG_MAX /* max value for a quad_t */
^~~~~~~~~~~
/usr/obj/usr/src/powerpc.powerpc/tmp/usr/include/machine/_limits.h:75:21: note: expanded from macro '__LLONG_MAX'
#define __LLONG_MAX 0x7fffffffffffffffLL /* max value for a long long */
^~~~~~~~~~~~~~~~~~~~
and many instances of:
lib/libc/quad/fixunsdfdi.c:73:17: error: shift count >= width of type [-Werror,-Wshift-count-overflow]
toppart = (x - ONE_HALF) / ONE;
^~~~~~~~
lib/libc/quad/fixunsdfdi.c:45:19: note: expanded from macro 'ONE_HALF'
#define ONE_HALF (ONE_FOURTH * 2.0)
^~~~~~~~~~
lib/libc/quad/fixunsdfdi.c:44:23: note: expanded from macro 'ONE_FOURTH'
#define ONE_FOURTH (1 << (LONG_BITS - 2))
^ ~~~~~~~~~~~~~~~
lib/libc/quad/fixunsdfdi.c:73:29: error: shift count >= width of type [-Werror,-Wshift-count-overflow]
toppart = (x - ONE_HALF) / ONE;
^~~
lib/libc/quad/fixunsdfdi.c:46:15: note: expanded from macro 'ONE'
#define ONE (ONE_FOURTH * 4.0)
^~~~~~~~~~
lib/libc/quad/fixunsdfdi.c:44:23: note: expanded from macro 'ONE_FOURTH'
#define ONE_FOURTH (1 << (LONG_BITS - 2))
^ ~~~~~~~~~~~~~~~
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
- Use a constant for the offset instead of a magic number.
- Use an addi instruction that writes to tp directly instead of a mv
that writes the result of a compiler-generated addi.
Reviewed by: mhorne
MFC after: 1 week
Sponsored by: DARPA
Differential Revision: https://reviews.freebsd.org/D23521
libssp_nonshared.a defines one symbol, __stack_chk_fail_local. This
is used only on i386 and powerpc; other archs emit calls directly to
__stack_chk_fail. Simplify linking on other archs by omitting it.
PR: 242941 [exp-run]
This appears to have been introduced in r173763. Also fix the confusing
indentation that probably led to the bug in the first place.
PR: 243759
Diagnosed by: martin@lispworks.com
MFC after: 2 weeks
Sponsored by: The FreeBSD Foundation
Among the same justification as the other stdio _unlocked; in addition to an
inline version in <stdio.h>, we must provide a function in libc as well for
the functionality. This fixes the lang/gcc* builds, which want to use the
symbol from libc.
PR: 243810
Reported by: antoine, swills, Michael <michael.adm gmail com>
X-MFC-With: r357284
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
rand(3)'s standard C API is extremely limiting, but we can do better
than the historical 32-bit state Park-Miller LCG we've shipped since
2001: r73156.
The justification provided at the time for not using random(3) was that
rand_r(3) could not be made to use the same algorithm. That is still
true. However, the irrelevance of rand_r(3) is increasingly obvious.
Since that time, POSIX has marked the interface obsolescent. rand_r(3)
never became part of the standard C library. If not for API
compatibility reasons, I would just remove rand_r(3) entirely.
So, I do not believe it is a problem for rand_r(3) and rand(3) to
diverge.
The 12 ABI is maintained with compatibility definitions, but this
revision does subtly change the API of rand(3). The sequences of
pseudorandom numbers produced in programs built against new versions of
libc will differ from programs built against prior versions of libc.
Reviewed by: kevans, markm
MFC after: no
Relnotes: yes
Differential Revision: https://reviews.freebsd.org/D23290
fflush_unlocked is currently desired in ports by sysutils/metalog, and
redefined as the locked fflush.
fputc_unlocked, fputs_unlocked, fread_unlocked, and fwrite_unlocked are
currently desired in ports by devel/elfutils, and redefined as the locked
fputs, fread, and fwrite respectively.
Reviewed by: kib
MFC after: 2 weeks
Differential Revision: https://reviews.freebsd.org/D23336
The existing APIs simply pass the implicit global state to the _r variants.
No functional change.
Note that these routines are not exported from libc and are not intended to be
exported. If someone wished to export them from libc (which I would
discourage), they should first be modified to match the inconsistent parameter
type / order of the glibc public interfaces of the same names.
I know Ravi will ask, so: the eventual goal of this series is to replace
rand(3) with the implementation from random(3) (D23290). However, I'd like to
wait a bit longer on that one to see if more feedback emerges.
Reviewed by: kevans, markm
Differential Revision: https://reviews.freebsd.org/D23289
As part of the FreeBSD powerpc* flag day (1300070), the auxv numbering was
changed to match every other platform.
See D20799 for more details on that change.
While the kernel and rtld were adapted, libc was not, so old dynamic
binaries broke for reasons other than the ABI change on powerpc64.
Since it's possible to support nearly everything regarding old binaries by
adding compatibility code to libc (as besides rtld, it is the main point
where auxv is digested), we might as well provide compatibility code.
The only unhandled case remaining should be "new format libraries that call
elf_aux_info() which are dynamically linked to by old-format binaries",
which should be quite rare.
Reviewed by: jhibbits
Sponsored by: Tag1 Consulting, Inc.
Differential Revision: https://reviews.freebsd.org/D23096
In the case of an error, the RFSPAWN'd thread will write back to psa->error
with the correct exit code. Mark this as volatile as the return value is
being actively dorked up for erroneous exits on !x86.
This fixes the following tests, tested on aarch64 (only under qemu, at the
moment):
- posix_spawn/spawn_test:t_spawn_missing
- posix_spawn/spawn_test:t_spawn_nonexec
- posix_spawn/spawn_test:t_spawn_zero
Reported by: mikael
MFC after: 3 days
to port software written for Linux variant of qsort_r(3).
Reviewed by: kib, arichardson
MFC after: 2 weeks
Relnotes: yes
Sponsored by: DARPA
Differential Revision: https://reviews.freebsd.org/D23174
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
For copies shorter than 512 bytes, the data is copied using plain
ld/std instructions.
For 512 bytes or more, the copy is done in 3 phases:
Phase 1: copy from the src buffer until it's aligned at a 16-byte boundary
Phase 2: copy as many aligned 64-byte blocks from the src buffer as possible
Phase 3: copy the remaining data, if any
In phase 2, this code uses VSX instructions when available. Otherwise,
it uses ldx/stdx.
Submitted by: Luis Pires <lffpires_ruabrasil.org> (original version)
Reviewed by: jhibbits
Differential Revision: https://reviews.freebsd.org/D15118
Assembly optimization of strncpy for PowerPC64, using double words
instead of bytes to copy strings.
Submitted by: Leonardo Bianconi <leonardo.bianconi_eldorado.org.br> (original version)
Reviewed by: jhibbits
Differential Revision: https://reviews.freebsd.org/D15369
Assembly optimization of strcpy for PowerPC64, using double words
instead of bytes to copy strings.
Submitted by: Leonardo Bianconi <leonardo.bianconi_eldorado.org.br> (original version)
Reviewed by: jhibbits
Differential Revision: https://reviews.freebsd.org/D15368
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
- Fix checks for mmap() failures. [1]
- Set the "map" and "maplen" fields of struct xlocale_collate so that
the table destructor actually does something.
- Free an already-mapped collation file before loading a new one into
the global table.
- Harmonize the prototype and definition of __collate_load_tables_l() by
adding the "static" qualifier to the latter.
PR: 243195
Reported by: cem [1]
Reviewed by: cem, yuripv
MFC after: 1 week
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D23109
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
I've been advised that the model that uses these are fairly resilient, but
we do know the proper path to use (or remove, in the case of ^/targets/...),
so go ahead and update them to reflect that.
A future commit will rebuild this as part of libssp. The exact warnings are
fairly trivially fixed:
- No previous declaration for __stack_chk_guard
- idx is the wrong type, nitems yields a size_t
- Casting away volatile on the tmp_stack_chk_guard directly is a no-no.
Reviewed by: kib, emaste, pfg, Oliver Pinter (earlier version)
MFC after: 1 week
Differential Revision: https://reviews.freebsd.org/D22943
Remove temporary compatibility layer introduced in r351729. More that 3 months
should be enough for everybody who runs HEAD to upgrade to the new kernel
already.
Reviewed by: imp, mjg (mentor)
Approved by: mjg (mentor)
Differential Revision: https://reviews.freebsd.org/D22958
This uses the new layout of the upstream repository, which was recently
migrated to GitHub, and converted into a "monorepo". That is, most of
the earlier separate sub-projects with their own branches and tags were
consolidated into one top-level directory, and are now branched and
tagged together.
Updating the vendor area to match this layout is next.
It serves no useful purpose and wasn't as popular as its equally meritless
cousin, srandomdev(3).
Setting aside the problems with rand(3) in general, the problem with this
interface is that the seed isn't shared with the caller (other than by
attacking the output of the generator, which is trivial, but not a hallmark of
pleasant API design). The (arguable) utility of rand(3) or random(3) is as a
semi-fast simulation generator which produces consistent results from a given
seed. These are mutually at odd. Furthermore, sometimes people got the
mistaken impression that a high quality random seed meant a weak generator like
rand(3) or random(3) could be used for things like cryptographic key
generation. This is absolutely not so.
The API was never part of a standard and was not widely used in tree. Existing
in-tree uses have all been removed.
Possible replacement in out of tree codebases:
char buf[3];
time_t t;
time(t);
strftime(buf, sizeof(buf), "%S", gmtime(&t));
srand(atoi(buf));
Relnotes: yes
The settings in arith.h were not fully defined on powerpc64 after the gdtoa
switchover. Generate them using arithchk.c, similar to what AMD64 did for
r114814.
Technically, none of this is necessary in FreeBSD gdtoa, but since the other
platforms have full definitions, we might as well have full definitions
too.
Approved by: jhibbits (in irc)
Differential Revision: https://reviews.freebsd.org/D22775
Fix multiple problems in the powerpcspe floating point code.
* Endianness handling of the SPEFSCR in fenv.h was completely broken.
* Ensure SPEFSCR synchronization requirements are being met.
The __r.__d -> __r transformations were written by jhibbits.
Reviewed by: jhibbits
Differential Revision: https://reviews.freebsd.org/D22526
These functions (sigandset, sigisemptyset, sigorset) are commonly available
in at least musl libc and glibc; sigorset, at least, has proven quite useful
in qemu-bsd-user work for tracking the current process signal mask in a more
self-documenting/aesthetically pleasing manner.
Reviewed by: bapt, jilles, pfg
MFC after: 1 week
Differential Revision: https://reviews.freebsd.org/D22187
Update a bunch of Makefile.depend files as
a result of adding Makefile.depend.options files
Reviewed by: bdrewery
MFC after: 1 week
Sponsored by: Juniper Networks
Differential Revision: https://reviews.freebsd.org/D22494
Leaf directories that have dependencies impacted
by options need a Makefile.depend.options file
to avoid churn in Makefile.depend
DIRDEPS for cases such as OPENSSL, TCP_WRAPPERS etc
can be set in local.dirdeps-options.mk
which can add to those set in Makefile.depend.options
See share/mk/dirdeps-options.mk
Reviewed by: bdrewery
MFC after: 1 week
Sponsored by: Juniper Networks
Differential Revision: https://reviews.freebsd.org/D22469
