The select function, fd_set, and FD_* macros were standardized by POSIX
in the sys/select.h header. They are still defined in sys/types.h if
__USE_MISC is defined, but we should recommend the more portable and
standardized sys/select.h.
Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
The original example works on glibc since sys/time.h includes
sys/select.h. However, since POSIX requires that select is defined in
sys/select.h this change makes the example more portable.
Reported by Gavin Smith <gavinsmith0123@gmail.com> in:
<https://lists.gnu.org/archive/html/bug-texinfo/2025-07/msg00091.html>.
Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
The getsubopt function was an XSI extension since POSIX issue 4 until it
was added to Base in POSIX Issue 7. This also adds the 'restrict'
qualifier to the arguments as done in POSIX.1-2024, and has been the
case in glibc.
Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
Secure mode is enabled only if SGID actually provides a new privilege,
so we have to drop it before gaining it again.
Fixes commit 3a3fb2ed83
("Fix error reporting (false negatives) in SGID tests")
Cleanup sysmalloc_mmap - simplify padding since it is always a constant.
Remove av parameter which is only used in do_check_chunk, but since it may be
NULL for mmap, it will cause a crash in checking mode. Remove the odd check
on mmap in do_check_chunk.
Reviewed-by: DJ Delorie <dj@redhat.com>
Change checked_request2size to return SIZE_MAX for huge inputs. This
ensures large allocation requests stay large and can't be confused with a
small allocation. As a result several existing checks against PTRDIFF_MAX
become redundant.
Reviewed-by: DJ Delorie <dj@redhat.com>
MAX_TCACHE_SMALL_SIZE should use chunk size since it is used after
checked_request2size. Increase limit of tcache_max_bytes by 1 since all
comparisons use '<'. As a result, the last tcache entry is now used as
expected.
Reviewed-by: DJ Delorie <dj@redhat.com>
The SYSCALL_CANCEL calls __syscall_cancel, which in turn
calls __internal_syscall_cancel with an 'int' return instead of the
expected 'long int'. This causes issues with syscalls that return
values larger than INT_MAX, such as copy_file_range [1].
Checked on x86_64-linux-gnu.
[1] https://debbugs.gnu.org/cgi/bugreport.cgi?bug=79139
Reviewed-by: Andreas K. Huettel <dilfridge@gentoo.org>
Consolidate subdirectory check on elf and csu to avoid checking them
more than once.
Signed-off-by: H.J. Lu <hjl.tools@gmail.com>
Reviewed-by: Sam James <sam@gentoo.org>
Consolidate subdirectory check on elf and csu to avoid checking them
more than once.
Signed-off-by: H.J. Lu <hjl.tools@gmail.com>
Reviewed-by: Sam James <sam@gentoo.org>
Detect if ld.so not contiguous and handle that case in _dl_find_object.
Set l_find_object_processed even for initially loaded link maps,
otherwise dlopen of an initially loaded object adds it to
_dlfo_loaded_mappings (where maps are expected to be contiguous),
in addition to _dlfo_nodelete_mappings.
Test elf/tst-link-map-contiguous-ldso iterates over the loader
image, reading every word to make sure memory is actually mapped.
It only does that if the l_contiguous flag is set for the link map.
Otherwise, it finds gaps with mmap and checks that _dl_find_object
does not return the ld.so mapping for them.
The test elf/tst-link-map-contiguous-main does the same thing for
the libc.so shared object. This only works if the kernel loaded
the main program because the glibc dynamic loader may fill
the gaps with PROT_NONE mappings in some cases, making it contiguous,
but accesses to individual words may still fault.
Test elf/tst-link-map-contiguous-libc is again slightly different
because the dynamic loader always fills the gaps with PROT_NONE
mappings, so a different form of probing has to be used.
Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
Remove historic binutils reference from comment and update
how this data is used by applications.
Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
The __abort_fork_reset_child (introduced in
d40ac01cbb) call resets the lock after the
fork. This causes a DRD regression in valgrind
(https://bugs.kde.org/show_bug.cgi?id=503668), as it's effectively a
double initialization, despite it being actually ok in this case. As
suggested in https://sourceware.org/bugzilla/show_bug.cgi?id=32994#c2
we replace it here with a memcpy of another initialized lock instead,
which makes valgrind happy.
Reviewed-by: Florian Weimer <fweimer@redhat.com>
Enable support for THP always when glibc.malloc.hugetlb=1, as the tunable
currently only gives explicit support in malloc for the THP madvise mode
by aligning to a huge page size. Add a thp_mode parameter to mp_ and check
in madvise_thp whether the system is using madvise mode, otherwise the
`__madvise` call is useless. Set the thp_mode to be unsupported by default,
but if the hugetlb tunable is set this updates thp_mode. Performance of
xalancbmk improves by 4.9% on Neoverse V2 when THP always mode is set on the
system and glibc.malloc.hugetlb=1.
Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
Commit 934d88d used inputs with exponent generated at random in the
whole binary64 exponent range, which yields essentially very large
or very small values of |y/x|. Instead, this commit generates x, y at
random in [-10,10], which should better corresponds to real applications.
Reviewed-by: Florian Weimer <fweimer@redhat.com>
It fixes ce488f7c16 which updated
the out files without using gen-auto-libm-tests.c instructions.
Checked on powerpc64le-linux-gnu.
Tested-by: Andreas K. Huettel <dilfridge@gentoo.org>
Reviewed-by: Carlos O'Donell <carlos@redhat.com>
This ensures that the compiler will not inline it, so that
debuggers which do not use the Systemtap probes can reliably
set a breakpoint on it.
Reviewed-by: Andreas K. Huettel <dilfridge@gentoo.org>
Tested-by: Andreas K. Huettel <dilfridge@gentoo.org>
If SFrame is enable check if DLFO_FLAG_SFRAME is set (since sframe
support is added by default) and if dlfo_sframe has the expected
value.
Checked on aarch64-linux-gnu and x86_64-linux-gnu.
Reviewed-by: Sam James <sam@gentoo.org>
The Sframe V2 has a new errata which introduces the
SFRAME_F_FDE_FUNC_START_PCREL flag. This flag indicates the encoding
of the SFrame FDE function start address field like this:
- if set, sfde_func_start_address field contains the offset in bytes
to the start PC of the associated function from the field itself.
- if unset, sfde_func_start_address field contains the offset in bytes
to the start PC of the associated function from the start of the
SFrame section.
Signed-off-by: Claudiu Zissulescu <claudiu.zissulescu-ianculescu@oracle.com>
Reviewed-by: Sam James <sam@gentoo.org>
And add extra checks to enable for binutils 2.45 and if the architecture
explicitly enables it. When SFrame is disabled, all the related code
is also not enabled for backtrace() and _dl_find_object(), so SFrame
backtracking is not used even if the binary has the SFrame segment.
This patch also adds some other related fixes:
* Fixed an issue with AC_CHECK_PROG_VER, where the READELF_SFRAME
usage prevented specifying a different readelf through READELF
environment variable at configure time.
* Add an extra arch-specific internal definition,
libc_cv_support_sframe, to disable --enable-sframe on architectures
that have binutils but not glibc support (s390x).
* Renamed the tests without the .sframe segment and move the
tst-backtrace1 from pthread to debug.
* Use the built compiler strip to remove the .sframe segment,
instead of the system one (which might not support SFrame).
Checked on x86_64-linux-gnu and aarch64-linux-gnu.
Reviewed-by: Sam James <sam@gentoo.org>
Wilco Dijkstra
Collin Funk
Luca Boccassi
Samuel Thibault
Florian Weimer
Adhemerval Zanella
H.J. Lu
Davide Cavalca
Joseph Myers
William Hunt
Paul Zimmermann
Sam James
Andreas K. Hüttel
Carlos O'Donell
Claudiu Zissulescu
Sachin Monga