Commit Graph

38883 Commits

Author SHA1 Message Date
Adhemerval Zanella
90cf8e6f0a microblaze: Remove _dl_skip_args usage
Since ad43cac44a the generic code already shuffles the argv/envp/auxv
on the stack to remove the ld.so own arguments and thus _dl_skip_args
is always 0.   So there is no need to adjust the argc or argv.

Checked with qemu-user that arguments are correctly passed on both
constructors and main program.

Reviewed-by: Carlos O'Donell <carlos@redhat.com>
2022-05-30 16:33:14 -03:00
Adhemerval Zanella
ee39fafa98 m68k: Remove _dl_skip_args usage
Since ad43cac44a the generic code already shuffles the argv/envp/auxv
on the stack to remove the ld.so own arguments and thus _dl_skip_args
is always 0.  So there is no need to adjust the argc or argv.

Checked with qemu-user that arguments are correctly passed on both
constructors and main program.

Reviewed-by: Carlos O'Donell <carlos@redhat.com>
2022-05-30 16:33:11 -03:00
Adhemerval Zanella
57bb1e5b9f ia64: Remove _dl_skip_args usage
Since ad43cac44a the generic code already shuffles the argv/envp/auxv
on the stack to remove the ld.so own arguments and thus _dl_skip_args
is always 0.

The startup code is changed to read the _dl_argc and _dl_argv values,
and envp is calculated from argc and argv.

Checked on ia64-linux-gnu.

Reviewed-by: Carlos O'Donell <carlos@redhat.com>
2022-05-30 16:33:08 -03:00
Adhemerval Zanella
1b7f05d11e i686: Remove _dl_skip_args usage
Since ad43cac44a the generic code already shuffles the argv/envp/auxv
on the stack to remove the ld.so own arguments and thus _dl_skip_args
is always 0.  So there is no need to adjust the argc or argv.

Checked on i686-linux-gnu.

Reviewed-by: H.J. Lu <hjl.tools@gmail.com>
2022-05-30 16:32:57 -03:00
Adhemerval Zanella
6242602273 hppa: Remove _dl_skip_args usage (BZ# 29165)
Different than other architectures, hppa creates an unrelated stack
frame where ld.so argc/argv adjustments done by ad43cac44a
is not done on the argc/argv saved/restore by _dl_start_user.

Instead load _dl_argc and _dl_argv directlty instead of adjust them
using _dl_skip_args value.

Checked on hppa-linux-gnu.

Reviewed-by: Carlos O'Donell <carlos@redhat.com>
2022-05-30 16:32:35 -03:00
Adhemerval Zanella
00477963c6 csky: Remove _dl_skip_args usage
Since ad43cac44a the generic code already shuffles the argv/envp/auxv
on the stack to remove the ld.so own arguments and thus _dl_skip_args
is always 0.  It makes the fixup_stack branch ununsed.

Reviewed-by: Carlos O'Donell <carlos@redhat.com>
2022-05-30 16:32:33 -03:00
Adhemerval Zanella
f20464e9e4 arc: Remove _dl_skip_args usage
Since ad43cac44a the generic code already shuffles the argv/envp/auxv
on the stack to remove the ld.so own arguments and thus _dl_skip_args
is always 0.  So there is no need to adjust the argc or argv.

Reviewed-by: Carlos O'Donell <carlos@redhat.com>
2022-05-30 16:32:29 -03:00
Adhemerval Zanella
49d877a80b arm: Remove _dl_skip_args usage
Since ad43cac44a the generic code already shuffles the argv/envp/auxv
on the stack to remove the ld.so own arguments and thus _dl_skip_args
is always 0.  It makes the _fixup_stack branch ununsed.

Checked with qemu-user that arguments are correctly passed on both
constructors and main program.

Reviewed-by: Carlos O'Donell <carlos@redhat.com>
2022-05-30 16:32:26 -03:00
Adhemerval Zanella
1e4fb2e1ab alpha: Remove _dl_skip_args usage
Since ad43cac44a the generic code already shuffles the argv/envp/auxv
on the stack to remove the ld.so own arguments and thus _dl_skip_args
is always 0.  It makes the fixup_stack branch ununsed.

Checked with qemu-user that arguments are correctly passed on both
constructors and main program.

Reviewed-by: Carlos O'Donell <carlos@redhat.com>
2022-05-30 16:32:22 -03:00
Noah Goldstein
a8f62164b1 benchtests: Improve benchtests for strstr, memmem, and memchr
1. Use json_ctx for output to help standardize format across all
   benchtests.

2. Add some additional tests to strstr and memchr expanding alignments
   and adding more small values.
Reviewed-by: H.J. Lu <hjl.tools@gmail.com>
2022-05-27 22:52:37 -05:00
Fangrui Song
efa7936e4c dlsym: Make RTLD_NEXT prefer default version definition [BZ #14932]
When the first object providing foo defines both foo@v1 and foo@@v2,
dlsym(RTLD_NEXT, "foo") returns foo@v1 while dlsym(RTLD_DEFAULT, "foo")
returns foo@@v2.  The issue is that RTLD_DEFAULT uses the
DL_LOOKUP_RETURN_NEWEST flag while RTLD_NEXT doesn't.  Fix the RTLD_NEXT
branch to use DL_LOOKUP_RETURN_NEWEST.

Note: the new behavior matches FreeBSD rtld.  Future sanitizers will not
need to add versioned interceptors like https://reviews.llvm.org/D96348

Reviewed-by: Adhemerval Zanella  <adhemerval.zanella@linaro.org>
2022-05-27 12:34:49 -07:00
H.J. Lu
f8587a6189 x86-64: Ignore r_addend for R_X86_64_GLOB_DAT/R_X86_64_JUMP_SLOT
According to x86-64 psABI, r_addend should be ignored for R_X86_64_GLOB_DAT
and R_X86_64_JUMP_SLOT.  Since linkers always set their r_addends to 0, we
can ignore their r_addends.

Reviewed-by: Fangrui Song <maskray@google.com>
2022-05-26 14:00:25 -07:00
Sunil K Pandey
9c66efb86f x86_64: Implement evex512 version of strlen, strnlen, wcslen and wcsnlen
This patch implements following evex512 version of string functions.
Perf gain for evex512 version is up to 50% as compared to evex,
depending on length and alignment.

Placeholder function, not used by any processor at the moment.

- String length function using 512 bit vectors.
- String N length using 512 bit vectors.
- Wide string length using 512 bit vectors.
- Wide string N length using 512 bit vectors.

Reviewed-by: Noah Goldstein <goldstein.w.n@gmail.com>
2022-05-26 13:11:36 -07:00
Joseph Myers
8d6c44ee7d Update kernel version to 5.18 in header constant tests
This patch updates the kernel version in the tests tst-mman-consts.py
and tst-pidfd-consts.py to 5.18.  (There are no new constants covered
by these tests in 5.18, or in 5.17 in the case of tst-pidfd-consts.py
that previously used version 5.16, that need any other header
changes.)

Tested with build-many-glibcs.py.
2022-05-26 13:51:17 +00:00
Sunil K Pandey
7597b251d4 String: Improve overflow test coverage for strnlen
This patch adds more overflow test coverage for strnlen and wcsnlen.

Reviewed-by: H.J. Lu <hjl.tools@gmail.com>
2022-05-25 14:23:54 -07:00
Joseph Myers
3d9926663c Update syscall-names.list for Linux 5.18
Linux 5.18 has no new syscalls.  Update the version number in
syscall-names.list to reflect that it is still current for 5.18.

Tested with build-many-glibcs.py.
2022-05-25 14:37:28 +00:00
Arjun Shankar
52a103e237 Fix deadlock when pthread_atfork handler calls pthread_atfork or dlclose
In multi-threaded programs, registering via pthread_atfork,
de-registering implicitly via dlclose, or running pthread_atfork
handlers during fork was protected by an internal lock.  This meant
that a pthread_atfork handler attempting to register another handler or
dlclose a dynamically loaded library would lead to a deadlock.

This commit fixes the deadlock in the following way:

During the execution of handlers at fork time, the atfork lock is
released prior to the execution of each handler and taken again upon its
return.  Any handler registrations or de-registrations that occurred
during the execution of the handler are accounted for before proceeding
with further handler execution.

If a handler that hasn't been executed yet gets de-registered by another
handler during fork, it will not be executed.   If a handler gets
registered by another handler during fork, it will not be executed
during that particular fork.

The possibility that handlers may now be registered or deregistered
during handler execution means that identifying the next handler to be
run after a given handler may register/de-register others requires some
bookkeeping.  The fork_handler struct has an additional field, 'id',
which is assigned sequentially during registration.  Thus, handlers are
executed in ascending order of 'id' during 'prepare', and descending
order of 'id' during parent/child handler execution after the fork.

Two tests are included:

* tst-atfork3: Adhemerval Zanella <adhemerval.zanella@linaro.org>
  This test exercises calling dlclose from prepare, parent, and child
  handlers.

* tst-atfork4: This test exercises calling pthread_atfork and dlclose
  from the prepare handler.

[BZ #24595, BZ #27054]

Co-authored-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
Reviewed-by: Adhemerval Zanella  <adhemerval.zanella@linaro.org>
2022-05-25 11:27:31 +02:00
Joseph Myers
31ec883990 Use Linux 5.18 in build-many-glibcs.py
This patch makes build-many-glibcs.py use Linux 5.18.

Tested with build-many-glibcs.py (host-libraries, compilers and glibcs
builds).
2022-05-24 13:51:24 +00:00
Florian Weimer
fe8ca369ad stdio-common: Simplify printf_unknown interface in vfprintf-internal.c
The called function does not use the args array, so there is no need
to produce it.

Reviewed-by: Adhemerval Zanella  <adhemerval.zanella@linaro.org>
2022-05-24 08:03:11 +02:00
Florian Weimer
46db978347 stdio-common: Move union printf_arg int <printf.h>
The type does not depend on wide vs narrow preprocessor macros,
so it does not need to be customized in stdio-common/printf-parse.h.

Reviewed-by: Adhemerval Zanella  <adhemerval.zanella@linaro.org>
2022-05-24 08:03:11 +02:00
Florian Weimer
800d535504 stdio-common: Add printf specifier registry to <printf.h>
Add  __printf_arginfo_table, __printf_function_table,
__printf_va_arg_table, __register_printf_specifier to
include/printf.h.
2022-05-24 08:03:11 +02:00
Fangrui Song
36c1dbaedd elf/dl-reloc.c: Copyright The GNU Toolchain Authors
by following 3.5. Update copyright information
on https://sourceware.org/glibc/wiki/Contribution%20checklist .
The change is advised by Carlos O'Donell.

Note: commit a8b11bd1f8 missed Signed-off-by tag
from Nicholas Guriev <nicholas@guriev.su>.
2022-05-23 19:16:05 -07:00
Noah Goldstein
a01a13601c benchtests: Improve bench-strnlen.c
1. Output results in json format so its easier to parse
2. Increase max alignment to `getpagesize () - 1` to make it possible
   to test page cross cases.
Reviewed-by: H.J. Lu <hjl.tools@gmail.com>
2022-05-23 18:14:06 -05:00
Adhemerval Zanella
efeb2bd1ab math: Add math-use-builtins-fabs (BZ#29027)
Both float, double, and _Float128 are assumed to be supported
(float and double already only uses builtins).  Only long double
is parametrized due GCC bug 29253 which prevents its usage on
powerpc.

It allows to remove i686, ia64, x86_64, powerpc, and sparc arch
specific implementation.

On ia64 it also fixes the sNAN handling:

  math/test-float64x-fabs
  math/test-ldouble-fabs

Checked on x86_64-linux-gnu, i686-linux-gnu, powerpc-linux-gnu,
powerpc64-linux-gnu, sparc64-linux-gnu, and ia64-linux-gnu.
2022-05-23 17:49:18 -03:00
Adhemerval Zanella
04b30fe4f8 linux: Add CLONE_NEWTIME from Linux 5.6 to bits/sched.h
It was added in commit 769071ac9f20b6a447410c7eaa55d1a5233ef40c.
2022-05-23 17:49:18 -03:00
Fangrui Song
a7629b1c1b Revert "[ARM][BZ #17711] Fix extern protected data handling"
This reverts commit 3bcea719dd.

Similar to commit e555954e02 for aarch64.

Reviewed-by: Szabolcs Nagy <szabolcs.nagy@arm.com>
2022-05-23 13:42:10 -07:00
Fangrui Song
e555954e02 Revert "[AArch64][BZ #17711] Fix extern protected data handling"
This reverts commit 0910702c4d.

Say both a.so and b.so define protected data symbol `var` and the executable
copy relocates var.  ELF_RTYPE_CLASS_EXTERN_PROTECTED_DATA has strange
semantics: a.so accesses the copy in the executable while b.so accesses its
own.  This behavior requires that (a) the compiler emits GOT-generating
relocations (b) the linker produces GLOB_DAT instead of RELATIVE.

Without the ELF_RTYPE_CLASS_EXTERN_PROTECTED_DATA code, b.so's GLOB_DAT
will bind to the executable (normal behavior).

For aarch64 it makes sense to restore the original behavior and don't
pay the ELF_RTYPE_CLASS_EXTERN_PROTECTED_DATA cost.  The behavior is very
unlikely used by anyone.

* Clang code generator treats STV_PROTECTED the same way as STV_HIDDEN:
  no GOT-generating relocation in the first place.
* gold and lld reject copy relocation on a STV_PROTECTED symbol.
* Nowadays -fpie/-fpic modes are popular.  GCC/Clang's codegen uses
  GOT-generating relocation when accessing an default visibility
  external symbol which avoids copy relocation.

Reviewed-by: Szabolcs Nagy <szabolcs.nagy@arm.com>
2022-05-23 13:37:05 -07:00
Nicholas Guriev
a8b11bd1f8 elf: Rewrite long RESOLVE_MAP macro to an always_inline static function
An __always_inline static function is better to find where exactly a
crash happens, so one can step into the function with GDB.

Reviewed-by: Fangrui Song <maskray@google.com>
2022-05-23 12:06:44 -07:00
Fangrui Song
748df8126a dlfcn: Move RTLD_DEFAULT/RTLD_NEXT outside __USE_GNU
POSIX reserves the RTLD_ namespace, and this is already reflected in our
conform tests.
Note: RTLD_DEFAULT and RTLD_NEXT appear in IEEE Std 1003.1-2004.  Many
systems (e.g. FreeBSD, musl) just define the macros unconditionally.

Reviewed-by: Florian Weimer <fweimer@redhat.com>
Tested-by: Florian Weimer <fweimer@redhat.com>
2022-05-23 10:23:23 -07:00
Noah Goldstein
9a421348cd elf: Optimize _dl_new_hash in dl-new-hash.h
Unroll slightly and enforce good instruction scheduling. This improves
performance on out-of-order machines. The unrolling allows for
pipelined multiplies.

As well, as an optional sysdep, reorder the operations and prevent
reassosiation for better scheduling and higher ILP. This commit
only adds the barrier for x86, although it should be either no
change or a win for any architecture.

Unrolling further started to induce slowdowns for sizes [0, 4]
but can help the loop so if larger sizes are the target further
unrolling can be beneficial.

Results for _dl_new_hash
Benchmarked on Tigerlake: 11th Gen Intel(R) Core(TM) i7-1165G7 @ 2.80GHz

Time as Geometric Mean of N=30 runs
Geometric of all benchmark New / Old: 0.674
  type, length, New Time, Old Time, New Time / Old Time
 fixed,      0,    2.865,     2.72,               1.053
 fixed,      1,    3.567,    2.489,               1.433
 fixed,      2,    2.577,    3.649,               0.706
 fixed,      3,    3.644,    5.983,               0.609
 fixed,      4,    4.211,    6.833,               0.616
 fixed,      5,    4.741,    9.372,               0.506
 fixed,      6,    5.415,    9.561,               0.566
 fixed,      7,    6.649,   10.789,               0.616
 fixed,      8,    8.081,   11.808,               0.684
 fixed,      9,    8.427,   12.935,               0.651
 fixed,     10,    8.673,   14.134,               0.614
 fixed,     11,    10.69,   15.408,               0.694
 fixed,     12,   10.789,   16.982,               0.635
 fixed,     13,   12.169,   18.411,               0.661
 fixed,     14,   12.659,   19.914,               0.636
 fixed,     15,   13.526,   21.541,               0.628
 fixed,     16,   14.211,   23.088,               0.616
 fixed,     32,   29.412,   52.722,               0.558
 fixed,     64,    65.41,  142.351,               0.459
 fixed,    128,  138.505,  295.625,               0.469
 fixed,    256,  291.707,  601.983,               0.485
random,      2,   12.698,   12.849,               0.988
random,      4,   16.065,   15.857,               1.013
random,      8,   19.564,   21.105,               0.927
random,     16,   23.919,   26.823,               0.892
random,     32,   31.987,   39.591,               0.808
random,     64,   49.282,   71.487,               0.689
random,    128,    82.23,  145.364,               0.566
random,    256,  152.209,  298.434,                0.51

Co-authored-by: Alexander Monakov <amonakov@ispras.ru>
Reviewed-by: Siddhesh Poyarekar <siddhesh@sourceware.org>
2022-05-23 10:38:40 -05:00
Noah Goldstein
3d155d4b6c nss: Optimize nss_hash in nss_hash.c
The prior unrolling didn't really do much as it left the dependency
chain between iterations. Unrolled the loop for 4 so 4x multiplies
could be pipelined in out-of-order machines.

Results for __nss_hash
Benchmarked on Tigerlake: 11th Gen Intel(R) Core(TM) i7-1165G7 @ 2.80GHz

Time as Geometric Mean of N=25 runs
Geometric of all benchmark New / Old: 0.845
  type, length, New Time, Old Time, New Time / Old Time
 fixed,      0,    4.019,    3.729,               1.078
 fixed,      1,     4.95,    5.707,               0.867
 fixed,      2,    5.152,    5.657,               0.911
 fixed,      3,    4.641,    5.721,               0.811
 fixed,      4,    5.551,     5.81,               0.955
 fixed,      5,    6.525,    6.552,               0.996
 fixed,      6,    6.711,    6.561,               1.023
 fixed,      7,    6.715,    6.767,               0.992
 fixed,      8,    7.874,    7.915,               0.995
 fixed,      9,    8.888,    9.767,                0.91
 fixed,     10,    8.959,    9.762,               0.918
 fixed,     11,    9.188,    9.987,                0.92
 fixed,     12,    9.708,   10.618,               0.914
 fixed,     13,   10.393,    11.14,               0.933
 fixed,     14,   10.628,   12.097,               0.879
 fixed,     15,   10.982,   12.965,               0.847
 fixed,     16,   11.851,   14.429,               0.821
 fixed,     32,   24.334,   34.414,               0.707
 fixed,     64,   55.618,   86.688,               0.642
 fixed,    128,  118.261,   224.36,               0.527
 fixed,    256,  256.183,  538.629,               0.476
random,      2,   11.194,   11.556,               0.969
random,      4,   17.516,   17.205,               1.018
random,      8,   23.501,   20.985,                1.12
random,     16,   28.131,   29.212,               0.963
random,     32,   35.436,   38.662,               0.917
random,     64,    45.74,   58.868,               0.777
random,    128,   75.394,  121.963,               0.618
random,    256,  139.524,  260.726,               0.535
Reviewed-by: Siddhesh Poyarekar <siddhesh@sourceware.org>
2022-05-23 10:38:40 -05:00
Noah Goldstein
319dddc143 benchtests: Add benchtests for dl_elf_hash, dl_new_hash and nss_hash
Benchtests are for throughput and include random / fixed size
benchmarks.
Reviewed-by: Siddhesh Poyarekar <siddhesh@sourceware.org>
2022-05-23 10:38:40 -05:00
Noah Goldstein
5f2f0f6977 nss: Add tests for the nss_hash in nss_hash.h
If we want to further optimize the function tests are needed.
Reviewed-by: Siddhesh Poyarekar <siddhesh@sourceware.org>
2022-05-23 10:38:40 -05:00
Noah Goldstein
6fd435485f elf: Add tests for the dl hash funcs (_dl_new_hash and _dl_elf_hash)
If we want to further optimize the functions tests are needed.
Reviewed-by: Siddhesh Poyarekar <siddhesh@sourceware.org>
2022-05-23 10:38:40 -05:00
Noah Goldstein
c4bd509d47 elf: Refactor dl_new_hash so it can be tested / benchmarked
No change to the code other than moving the function to
dl-new-hash.h. Changed name so its now in the reserved namespace.
Reviewed-by: Siddhesh Poyarekar <siddhesh@sourceware.org>
2022-05-23 10:38:40 -05:00
Florian Weimer
93ec1cf0fe locale: Add more cached data to LC_CTYPE
This data will be used in number formatting.

Reviewed-by: Adhemerval Zanella  <adhemerval.zanella@linaro.org>
2022-05-23 11:06:31 +02:00
Florian Weimer
7ee41feba6 locale: Remove private union from struct __locale_data
This avoids an alias violation later.  This commit also fixes
an incorrect double-checked locking idiom in _nl_init_era_entries.

Reviewed-by: Adhemerval Zanella  <adhemerval.zanella@linaro.org>
2022-05-23 11:06:31 +02:00
Florian Weimer
bbebe83a28 locale: Remove cleanup function pointer from struct __localedata
We can call the cleanup functions directly from _nl_unload_locale
if we pass the category to it.

Reviewed-by: Adhemerval Zanella  <adhemerval.zanella@linaro.org>
2022-05-23 11:06:31 +02:00
Florian Weimer
0b6342e769 locale: Call _nl_unload_locale from _nl_archive_subfreeres
The function performs the same steps for ld_archive locales
(mapped from an archive), and this code is not performance-critical,
so the specialization does not add value.

Reviewed-by: Adhemerval Zanella  <adhemerval.zanella@linaro.org>
2022-05-23 11:06:31 +02:00
Florian Weimer
0060a6de54 stdio-common: Add tst-memstream-string for open_memstream overflow
This code path is exercised indirectly by some of the DNS stub
resolver tests, via their own use of xopen_memstream for constructing
strings describing result data.  The relative lack of test suite
coverage became apparent when these tests starting failing after a
printf changes uncovered bug 28949.

Reviewed-by: Adhemerval Zanella  <adhemerval.zanella@linaro.org>
2022-05-23 11:06:31 +02:00
Florian Weimer
b094c52b1b __printf_fphex always uses LC_NUMERIC
There is no hexadecimal currency printing.  strfmon uses
__printf_fp_l exclusively.

Reviewed-by: Adhemerval Zanella  <adhemerval.zanella@linaro.org>
2022-05-23 11:06:31 +02:00
Florian Weimer
859e7a00af vfprintf: Consolidate some multibyte/wide character processing
form_character and form_string processing a sufficiently similar
that the logic can be shared.

Reviewed-by: Adhemerval Zanella  <adhemerval.zanella@linaro.org>
2022-05-23 11:06:31 +02:00
Florian Weimer
5442ea7ffe vfprintf: Move argument processing into vfprintf-process-arg.c
This simplies formatting and helps with debugging.  It also allows
the use of localized COMPILE_WPRINTF preprocessor conditionals.

Reviewed-by: Adhemerval Zanella  <adhemerval.zanella@linaro.org>
2022-05-23 11:06:31 +02:00
Florian Weimer
21bb8382b6 stdio-common: Add tst-vfprintf-width-i18n to cover numeric field width
Related to bug 28943 and bug 28944.

Reviewed-by: Adhemerval Zanella  <adhemerval.zanella@linaro.org>
2022-05-23 11:06:31 +02:00
Sergei Trofimovich
5a5f94af05 string.h: fix __fortified_attr_access macro call [BZ #29162]
commit e938c0274 "Don't add access size hints to fortifiable functions"
converted a few '__attr_access ((...))' into '__fortified_attr_access (...)'
calls.

But one of conversions had double parentheses of '__fortified_attr_access (...)'.

Noticed as a gnat6 build failure:

    /<<NIX>>-glibc-2.34-210-dev/include/bits/string_fortified.h:110:50: error: macro "__fortified_attr_access" requires 3 arguments, but only 1 given

The change fixes parentheses.

This is seen when using compilers that do not support
__builtin___stpncpy_chk, e.g. gcc older than 4.7, clang older than 2.6
or some compiler not derived from gcc or clang.

Signed-off-by: Sergei Trofimovich <slyich@gmail.com>
Reviewed-by: Siddhesh Poyarekar <siddhesh@sourceware.org>
2022-05-23 13:56:43 +05:30
H.J. Lu
2d5ec6692f Enable DT_RELR in glibc shared libraries and PIEs automatically
Enable DT_RELR in glibc shared libraries and position independent
executables (PIE) automatically if linker supports -z pack-relative-relocs.
Reviewed-by: Florian Weimer <fweimer@redhat.com>
2022-05-18 13:04:13 -07:00
Stefan Liebler
728894dba4 S390: Enable static PIE
This commit enables static PIE on 64bit.  On 31bit, static PIE is
not supported.

A new configure check in sysdeps/s390/s390-64/configure.ac also performs
a minimal test for requirements in ld:
Ensure you also have those patches for:
- binutils (ld)
  - "[PR ld/22263] s390: Avoid dynamic TLS relocs in PIE"
    https://sourceware.org/git/?p=binutils-gdb.git;a=commit;h=26b1426577b5dcb32d149c64cca3e603b81948a9
    (Tested by configure check above)
    Otherwise there will be a R_390_TLS_TPOFF relocation, which fails to
    be processed in _dl_relocate_static_pie() as static TLS map is not setup.
  - "s390: Add DT_JMPREL pointing to .rela.[i]plt with static-pie"
    https://sourceware.org/git/?p=binutils-gdb.git;a=commit;h=d942d8db12adf4c9e5c7d9ed6496a779ece7149e
    (We can't test it in configure as we are not able to link a static PIE
    executable if the system glibc lacks static PIE support)
    Otherwise there won't be DT_JMPREL, DT_PLTRELA, DT_PLTRELASZ entries
    and the IFUNC symbols are not processed, which leads to crashes.

- kernel (the mentioned links to the commits belong to 5.19 merge window):
  - "s390/mmap: increase stack/mmap gap to 128MB"
    https://git.kernel.org/pub/scm/linux/kernel/git/s390/linux.git/commit/?h=features&id=f2f47d0ef72c30622e62471903ea19446ea79ee2
  - "s390/vdso: move vdso mapping to its own function"
    https://git.kernel.org/pub/scm/linux/kernel/git/s390/linux.git/commit/?h=features&id=57761da4dc5cd60bed2c81ba0edb7495c3c740b8
  - "s390/vdso: map vdso above stack"
    https://git.kernel.org/pub/scm/linux/kernel/git/s390/linux.git/commit/?h=features&id=9e37a2e8546f9e48ea76c839116fa5174d14e033
  - "s390/vdso: add vdso randomization"
    https://git.kernel.org/pub/scm/linux/kernel/git/s390/linux.git/commit/?h=features&id=41cd81abafdc4e58a93fcb677712a76885e3ca25
  (We can't test the kernel of the target system)
  Otherwise if /proc/sys/kernel/randomize_va_space is turned off (0),
  static PIE executables like ldconfig will crash.  While startup sbrk is
  used to enlarge the HEAP.  Unfortunately the underlying brk syscall fails
  as there is not enough space after the HEAP.  Then the address of the TLS
  image is invalid and the following memcpy in __libc_setup_tls() leads
  to a segfault.
  If /proc/sys/kernel/randomize_va_space is activated (default: 2), there
  is enough space after HEAP.

- glibc
  - "Linux: Define MMAP_CALL_INTERNAL"
    https://sourceware.org/git/?p=glibc.git;a=commit;h=c1b68685d438373efe64e5f076f4215723004dfb
  - "i386: Remove OPTIMIZE_FOR_GCC_5 from Linux libc-do-syscall.S"
    https://sourceware.org/git/?p=glibc.git;a=commit;h=6e5c7a1e262961adb52443ab91bd2c9b72316402
  - "i386: Honor I386_USE_SYSENTER for 6-argument Linux system calls"
    https://sourceware.org/git/?p=glibc.git;a=commit;h=60f0f2130d30cfd008ca39743027f1e200592dff
  - "ia64: Always define IA64_USE_NEW_STUB as a flag macro"
    https://sourceware.org/git/?p=glibc.git;a=commit;h=18bd9c3d3b1b6a9182698c85354578d1d58e9d64
  - "Linux: Implement a useful version of _startup_fatal"
    https://sourceware.org/git/?p=glibc.git;a=commit;h=a2a6bce7d7e52c1c34369a7da62c501cc350bc31
  - "Linux: Introduce __brk_call for invoking the brk system call"
    https://sourceware.org/git/?p=glibc.git;a=commit;h=b57ab258c1140bc45464b4b9908713e3e0ee35aa
  - "csu: Implement and use _dl_early_allocate during static startup"
    https://sourceware.org/git/?p=glibc.git;a=commit;h=f787e138aa0bf677bf74fa2a08595c446292f3d7
  The mentioned patch series by Florian Weimer avoids the mentioned failing
  sbrk syscall by falling back to mmap.

This commit also adjusts startup code in start.S to be ready for static PIE.
We have to add a wrapper function for main as we are not allowed to use
GOT relocations before __libc_start_main is called.
(Compare also to:
- commit 14d886edbd
  "aarch64: fix start code for static pie"
- commit 3d1d79283e
  "aarch64: fix static pie enabled libc when main is in a shared library"
)
2022-05-18 14:31:26 +02:00
Adhemerval Zanella
d2a1ec2097 linux: Add tst-pidfd.c
To check for the pidfd functions pidfd_open, pidfd_getfd, pid_send_signal,
and waitid with P_PIDFD.

Checked on x86_64-linux-gnu and i686-linux-gnu.

Reviewed-by: Carlos O'Donell <carlos@redhat.com>
Tested-by: Carlos O'Donell <carlos@redhat.com>
2022-05-17 10:36:59 -03:00
Adhemerval Zanella
b3528b0048 linux: Add P_PIDFD
It was added on Linux 5.4 (3695eae5fee0605f316fbaad0b9e3de791d7dfaf)
to extend waitid to wait on pidfd.

Reviewed-by: Carlos O'Donell <carlos@redhat.com>
Tested-by: Carlos O'Donell <carlos@redhat.com>
2022-05-17 10:34:36 -03:00
Adhemerval Zanella
56cf9e8eec linux: Add pidfd_send_signal
This was added on Linux 5.1(3eb39f47934f9d5a3027fe00d906a45fe3a15fad)
as a way to avoid the race condition of using kill (where PID might be
reused by the kernel between between obtaining the pid and sending the
signal).

If the siginfo_t argument is NULL then pidfd_send_signal is equivalent
to kill.  If it is not NULL pidfd_send_signal is equivalent to
rt_sigqueueinfo.

Reviewed-by: Carlos O'Donell <carlos@redhat.com>
Tested-by: Carlos O'Donell <carlos@redhat.com>
2022-05-17 10:33:46 -03:00