Wilco Dijkstra [Fri, 28 Feb 2025 16:52:25 +0000 (16:52 +0000)]
Remove unused dl-procinfo.h
Remove unused _dl_hwcap_string defines. As a result many dl-procinfo.h headers
can be removed. This also removes target specific _dl_procinfo implementations
which only printed HWCAP strings using dl_hwcap_string.
This looks really bad, with expensive movfr2gr instructions, redundant
sign-extensions and masking (arguably it's a compiler
missed-optimzation), and a branch. Rewrite it with inline assembly:
Note that we cannot make it more readable with
"double a = __builtin_isnanf (x) ? y : x" because this C statement only
happens to produce what we want with https://gcc.gnu.org/PR66462, if
this bug is fixed in the future the generated code may change.
Sergei Zimmerman [Tue, 25 Feb 2025 18:05:40 +0000 (18:05 +0000)]
sysdeps/ieee754: Fix remainder sign of zero for FE_DOWNWARD (BZ #32711)
Single-precision remainderf() and quad-precision remainderl()
implementation derived from Sun is affected by an issue when the result
is +-0. IEEE754 requires that if remainder(x, y) = 0, its sign shall be
that of x regardless of the rounding direction.
The implementation seems to have assumed that x - x = +0 in all
rounding modes, which is not the case. When rounding direction is
roundTowardNegative the sign of an exact zero sum (or difference) is −0.
Regression tests that triggered this erroneous behavior are added to
math/libm-test-remainder.inc.
math: Add optimization barrier to ensure a1 + u.d is not reused [BZ #30664]
A number of fma tests started to fail on hppa when gcc was changed to
use Ranger rather than EVRP. Eventually I found that the value of
a1 + u.d in this is block of code was being computed in FE_TOWARDZERO
mode and not the original rounding mode:
if (TININESS_AFTER_ROUNDING)
{
w.d = a1 + u.d;
if (w.ieee.exponent == 109)
return w.d * 0x1p-108;
}
This caused the exponent value to be wrong and the wrong return path
to be used.
Here we add an optimization barrier after the rounding mode is reset
to ensure that the previous value of a1 + u.d is not reused.
Signed-off-by: John David Anglin <dave.anglin@bell.net>
Yangyu Chen [Mon, 24 Feb 2025 17:12:19 +0000 (01:12 +0800)]
RISC-V: Fix IFUNC resolver cannot access gp pointer
In some cases, an IFUNC resolver may need to access the gp pointer to
access global variables. Such an object may have l_relocated == 0 at
this time. In this case, an IFUNC resolver will fail to access a global
variable and cause a SIGSEGV.
This patch fixes this issue by relaxing the check of l_relocated in
elf_machine_runtime_setup, but added a check for SHARED case to avoid
using this code in static-linked executables. Such object have already
set up the gp pointer in load_gp function and l->l_scope will be NULL if
it is a pie object. So if we use these code to set up the gp pointer
again for static-pie, it will causing a SIGSEGV in glibc as original bug
on BZ #31317.
I have also reproduced and checked BZ #31317 using the mold commit bed5b1731b ("illumos: Treat absolute symbols specially"), this patch can
fix the issue.
Also, we used the wrong gp pointer previously because ref->st_value is
not the relocated address but just the offset from the base address of
ELF. An edge case may happen if we reference gp pointer in a IFUNC
resolver in a PIE object, but it will not happen in compiler-generated
codes since -pie will disable relax to gp. In this case, the GP will be
initialized incorrectly since the ref->st_value is not the address after
relocation. This patch fixes this issue by adding the l->l_addr to
ref->st_value to get the relocated address for the gp pointer. We don't
use SYMBOL_ADDRESS macro here because __global_pointer$ is a special
symbol that has SHN_ABS type, but it will use PC-relative addressing in
the load_gp function using lla.
Closes: BZ #32269 Fixes: 96d1b9ac23 ("RISC-V: Fix the static-PIE non-relocated object check") Co-authored-by: Vivian Wang <dramforever@live.com> Signed-off-by: Yangyu Chen <cyy@cyyself.name>
Stefan Liebler [Mon, 24 Feb 2025 13:13:00 +0000 (14:13 +0100)]
Increase the amount of data tested in stdio-common/tst-fwrite-pipe.c
The number of iterations and the length of the string are not high
enough on some systems causing the test to return false-positives.
Testcase stdio-common/tst-fwrite-bz29459.c was fixed in the same way in 1b6f868625403d6b7683af840e87d2b18d5d7731
(Increase the amount of data tested in stdio-common/tst-fwrite-bz29459.c, 2025-02-14)
Testcases stdio-common/tst-fwrite-bz29459.c and stdio-common/tst-fwrite-pipe.c
were introcued in 596a61cf6b51ce2d58b8ca4e1d1f4fdfe1440dbc
(libio: Start to return errors when flushing fwrite's buffer [BZ #29459], 2025-01-28)
Frédéric Bérat [Fri, 29 Nov 2024 13:48:43 +0000 (14:48 +0100)]
support: Add support_next_to_fault_before support function
Refactor the support_next_to_fault and add the
support_next_to_fault_before method returns a buffer with a protected
page before it, to be able to test buffer underflow accesses.
Reviewed-by: Tulio Magno Quites Machado Filho <tuliom@redhat.com>
koraynilay [Sat, 22 Feb 2025 14:55:59 +0000 (15:55 +0100)]
math: Fix `unknown type name '__float128'` for clang 3.4 to 3.8.1 (bug 32694)
When compiling a program that includes <bits/floatn.h> using a clang version
between 3.4 (included) and 3.8.1 (included), clang will fail with `unknown type
name '__float128'; did you mean '__cfloat128'?`. This changes fixes the clang
prerequirements macro call in floatn.h to check for clang 3.9 instead of 3.4,
since support for __float128 was actually enabled in 3.9 by:
Michael Jeanson [Fri, 14 Feb 2025 18:54:22 +0000 (13:54 -0500)]
nptl: clear the whole rseq area before registration
Due to the extensible nature of the rseq area we can't explictly
initialize fields that are not part of the ABI yet. It was agreed with
upstream that all new fields will be documented as zero initialized by
userspace. Future kernels configured with CONFIG_DEBUG_RSEQ will
validate the content of all fields during registration.
Replace the explicit field initialization with a memset of the whole
rseq area which will cover fields as they are added to future kernels.
Signed-off-by: Michael Jeanson <mjeanson@efficios.com> Reviewed-by: Florian Weimer <fweimer@redhat.com>
Yury Khrustalev [Tue, 21 Jan 2025 13:33:20 +0000 (13:33 +0000)]
aarch64: Add tests for Guarded Control Stack
These tests validate that GCS tunable works as expected depending
on the GCS markings in the test binaries.
Tests validate both static and dynamically linked binaries.
These new tests are AArch64 specific. Moreover, they are included only
if linker supports the "-z gcs=<value>" option. If built, these tests
will run on systems with and without HWCAP_GCS. In the latter case the
tests will be reported as UNSUPPORTED.
Carlos O'Donell [Thu, 20 Feb 2025 01:52:14 +0000 (20:52 -0500)]
manual: Mark setlogmask as AS-unsafe and AC-unsafe.
This fixes the check-safety.sh failure with commit ad9c4c536115ba38be3e63592a632709ec8209b4, and correctly marks
the function AS-unsafe and AC-unsafe due to the use of the
non-recursive lock.
Tested on x86_64 without regressions. Reviewed-by: Frédéric Bérat <fberat@redhat.com>
Wilco Dijkstra [Tue, 24 Dec 2024 18:01:59 +0000 (18:01 +0000)]
AArch64: Add SVE memset
Add SVE memset based on the generic memset with predicated load for sizes < 16.
Unaligned memsets of 128-1024 are improved by ~20% on average by using aligned
stores for the last 64 bytes. Performance of random memset benchmark improves
by ~2% on Neoverse V1.
H.J. Lu [Wed, 19 Feb 2025 23:08:26 +0000 (07:08 +0800)]
x86 (__HAVE_FLOAT128): Defined to 0 for Intel SYCL compiler [BZ #32723]
Intel compiler always defines __INTEL_LLVM_COMPILER. When SYCL is
enabled by -fsycl, it also defines SYCL_LANGUAGE_VERSION. Since Intel
SYCL compiler doesn't support _Float128:
https://github.com/intel/llvm/issues/16903
define __HAVE_FLOAT128 to 0 for Intel SYCL compiler.
This fixes BZ #32723.
Signed-off-by: H.J. Lu <hjl.tools@gmail.com> Reviewed-by: Sam James <sam@gentoo.org>
Aurelien Jarno [Sat, 15 Feb 2025 10:08:33 +0000 (11:08 +0100)]
Fix tst-aarch64-pkey to handle ENOSPC as not supported
The syscall pkey_alloc can return ENOSPC to indicate either that all
keys are in use or that the system runs in a mode in which memory
protection keys are disabled. In such case the test should not fail and
just return unsupported.
This matches the behaviour of the generic tst-pkey.
Florian Weimer [Thu, 13 Feb 2025 20:56:52 +0000 (21:56 +0100)]
elf: Keep using minimal malloc after early DTV resize (bug 32412)
If an auditor loads many TLS-using modules during startup, it is
possible to trigger DTV resizing. Previously, the DTV was marked
as allocated by the main malloc afterwards, even if the minimal
malloc was still in use. With this change, _dl_resize_dtv marks
the resized DTV as allocated with the minimal malloc.
The new test reuses TLS-using modules from other auditing tests.
Ben Kallus [Tue, 11 Feb 2025 19:29:51 +0000 (14:29 -0500)]
malloc: Add size check when moving fastbin->tcache
By overwriting a forward link in a fastbin chunk that is subsequently
moved into the tcache, it's possible to get malloc to return an
arbitrary address [0].
When a chunk is fetched from a fastbin, its size is checked against the
expected chunk size for that fastbin (see malloc.c:3991). This patch
adds a similar check for chunks being moved from a fastbin to tcache,
which renders obsolete the exploitation technique described above.
Now updated to use __glibc_unlikely instead of __builtin_expect, as
requested.
nss: Improve network number parsers (bz 32573, 32575)
Make sure that numbers never overflow uint32_t in inet_network to
properly validate octets encountered in IPv4 addresses.
Avoid malloca in NSS networks file code because /etc/networks lines
can be arbitrarily long. Instead of handcrafting the input for
inet_network by adding ".0" octets if they are missing, just left shift
the result. Also, do not accept invalid entries, but ignore the line
instead.
Luna Lamb [Thu, 13 Feb 2025 17:54:46 +0000 (17:54 +0000)]
Aarch64: Improve codegen in SVE exp and users, and update expf_inline
Use unpredicted muls, and improve memory access.
7%, 3% and 1% improvement in throughput microbenchmark on Neoverse V1,
for exp, exp2 and cosh respectively.
Wilco Dijkstra [Fri, 13 Dec 2024 15:43:07 +0000 (15:43 +0000)]
math: Improve layout of exp/exp10 data
GCC aligns global data to 16 bytes if their size is >= 16 bytes. This patch
changes the exp_data struct slightly so that the fields are better aligned
and without gaps. As a result on targets that support them, more load-pair
instructions are used in exp. Exp10 is improved by moving invlog10_2N later
so that neglog10_2hiN and neglog10_2loN can be loaded using load-pair.
The exp benchmark improves 2.5%, "144bits" by 7.2%, "768bits" by 12.7% on
Neoverse V2. Exp10 improves by 1.5%.
The libm size improvement built with "--enable-stack-protector=strong
--enable-bind-now=yes --enable-fortify-source=2":
Before:
text data bss dec hex filename
585192 860 12 586064 8f150 aarch64-linux-gnu/math/libm.so
960775 1068 12 961855 ead3f x86_64-linux-gnu/math/libm.so 1189174 5544 368 1195086 123c4e powerpc64le-linux-gnu/math/libm.so
After:
text data bss dec hex filename
584952 860 12 585824 8f060 aarch64-linux-gnu/math/libm.so
960615 1068 12 961695 eac9f x86_64-linux-gnu/math/libm.so 1189078 5544 368 1194990 123bee powerpc64le-linux-gnu/math/libm.so
The are small code changes for x86_64 and powerpc64le, which do not
affect performance; but on aarch64 with gcc-14 I see a slight better
code generation due the usage of ldq for floating point constant loading. Reviewed-by: Andreas K. Huettel <dilfridge@gentoo.org>
math: Consolidate acoshf and asinhf internal tables
The libm size improvement built with "--enable-stack-protector=strong
--enable-bind-now=yes --enable-fortify-source=2":
Before:
text data bss dec hex filename
587304 860 12 588176 8f990 aarch64-linux-gnu-master/math/libm.so
962855 1068 12 963935 eb55f x86_64-linux-gnu-master/math/libm.so 1191222 5544 368 1197134 12444e powerpc64le-linux-gnu-master/math/libm.so
After:
text data bss dec hex filename
585192 860 12 586064 8f150 aarch64-linux-gnu/math/libm.so
960775 1068 12 961855 ead3f x86_64-linux-gnu/math/libm.so 1189174 5544 368 1195086 123c4e powerpc64le-linux-gnu/math/libm.so
The are small code changes for x86_64 and powerpc64le, which do not
affect performance; but on aarch64 with gcc-14 I see a slight better
code generation due the usage of ldq for floating point constant loading. Reviewed-by: Andreas K. Huettel <dilfridge@gentoo.org>
DJ Delorie [Fri, 17 Jan 2025 22:34:02 +0000 (17:34 -0500)]
manual: Update signal descriptions
Based on auditing all the signals and source trees for Hurd and
Linux...
SIGSYS - This is not used for a bad system call (ENOSYS is used
for that). This is used by SECCOMP and some cases where an invalid
sub-function was requested.
SIGSTKFLT - Note it used to be a coprocessor stack fault but is now
obsolete and available for general user use.
SIGLOST - Hurd only now; note that its original purpose as an NFS
lock lost signal is obsolete.
SIGPWR - Note this is for power lost *and* power restored, and is
more a user-mode signal than a kernel-generated signal.
DJ Delorie [Tue, 10 Dec 2024 21:57:21 +0000 (16:57 -0500)]
manual: make @manpageurl more specific to each output
Tweak the @manpageurl macro to customize the output for
each of html, info, and pdf output. HTML and PDF (at
least, these days) support clicking on the link title,
whereas info does not. Add text to the intro section
explaining which man pages are normative and which
aren't.
Florian Weimer [Sun, 2 Feb 2025 19:10:09 +0000 (20:10 +0100)]
elf: Merge __dl_libc_freemem into __rtld_libc_freeres
The functions serve very similar purposes. The advantage of
__rtld_libc_freeres is that it is located within ld.so, so it is
more natural to poke at link map internals there.
This slightly regresses cleanup capabilities for statically linked
binaries. If that becomes a problem, we should start calling
__rtld_libc_freeres from __libc_freeres (perhaps after renaming it).
projects / thirdparty / glibc.git / log
