Commit Graph

2074 Commits

Author SHA1 Message Date
Manjunath Matti
ee7f4c54e1 powerpc: Add HWCAP3/HWCAP4 data to TCB for Power Architecture.
This patch adds a new feature for powerpc.  In order to get faster
access to the HWCAP3/HWCAP4 masks, similar to HWCAP/HWCAP2 (i.e. for
implementing __builtin_cpu_supports() in GCC) without the overhead of
reading them from the auxiliary vector, we now reserve space for them
in the TCB.

Suggested-by: Peter Bergner <bergner@linux.ibm.com>
Reviewed-by: Peter Bergner <bergner@linux.ibm.com>
(cherry picked from commit 3ab9b88e2a)
2024-03-20 18:09:32 -05:00
Xi Ruoyao
5a85786a90
Make __getrandom_nocancel set errno and add a _nostatus version
The __getrandom_nocancel function returns errors as negative values
instead of errno.  This is inconsistent with other _nocancel functions
and it breaks "TEMP_FAILURE_RETRY (__getrandom_nocancel (p, n, 0))" in
__arc4random_buf.  Use INLINE_SYSCALL_CALL instead of
INTERNAL_SYSCALL_CALL to fix this issue.

But __getrandom_nocancel has been avoiding from touching errno for a
reason, see BZ 29624.  So add a __getrandom_nocancel_nostatus function
and use it in tcache_key_initialize.

Signed-off-by: Xi Ruoyao <xry111@xry111.site>
Reviewed-by: Adhemerval Zanella  <adhemerval.zanella@linaro.org>
Signed-off-by: Andreas K. Hüttel <dilfridge@gentoo.org>
2024-01-12 14:23:11 +01:00
Adhemerval Zanella
460860f457 Remove ia64-linux-gnu
Linux 6.7 removed ia64 from the official tree [1], following the general
principle that a glibc port needs upstream support for the architecture
in all the components it depends on (binutils, GCC, and the Linux
kernel).

Apart from the removal of sysdeps/ia64 and sysdeps/unix/sysv/linux/ia64,
there are updates to various comments referencing ia64 for which removal
of those references seemed appropriate. The configuration is removed
from README and build-many-glibcs.py.

The CONTRIBUTED-BY, elf/elf.h, manual/contrib.texi (the porting
mention), *.po files, config.guess, and longlong.h are not changed.

For Linux it allows cleanup some clone2 support on multiple files.

The following bug can be closed as WONTFIX: BZ 22634 [2], BZ 14250 [3],
BZ 21634 [4], BZ 10163 [5], BZ 16401 [6], and BZ 11585 [7].

[1] https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=43ff221426d33db909f7159fdf620c3b052e2d1c
[2] https://sourceware.org/bugzilla/show_bug.cgi?id=22634
[3] https://sourceware.org/bugzilla/show_bug.cgi?id=14250
[4] https://sourceware.org/bugzilla/show_bug.cgi?id=21634
[5] https://sourceware.org/bugzilla/show_bug.cgi?id=10163
[6] https://sourceware.org/bugzilla/show_bug.cgi?id=16401
[7] https://sourceware.org/bugzilla/show_bug.cgi?id=11585
Reviewed-by: Carlos O'Donell <carlos@redhat.com>
2024-01-08 17:09:36 -03:00
Paul Eggert
dff8da6b3e Update copyright dates with scripts/update-copyrights 2024-01-01 10:53:40 -08:00
H.J. Lu
8d9f9c4460 elf: Always provide _dl_get_dl_main_map in libc.a
Always provide _dl_get_dl_main_map in libc.a.  It will be used by x86
to process PT_GNU_PROPERTY segment.
2024-01-01 05:22:48 -08:00
Adhemerval Zanella
2a969b53c0 elf: Do not duplicate the GLIBC_TUNABLES string
The tunable parsing duplicates the tunable environment variable so it
null-terminates each one since it simplifies the later parsing. It has
the drawback of adding another point of failure (__minimal_malloc
failing), and the memory copy requires tuning the compiler to avoid mem
operations calls.

The parsing now tracks the tunable start and its size. The
dl-tunable-parse.h adds helper functions to help parsing, like a strcmp
that also checks for size and an iterator for suboptions that are
comma-separated (used on hwcap parsing by x86, powerpc, and s390x).

Since the environment variable is allocated on the stack by the kernel,
it is safe to keep the references to the suboptions for later parsing
of string tunables (as done by set_hwcaps by multiple architectures).

Checked on x86_64-linux-gnu, powerpc64le-linux-gnu, and
aarch64-linux-gnu.
Reviewed-by: Siddhesh Poyarekar <siddhesh@sourceware.org>
2023-12-19 13:25:45 -03:00
Adhemerval Zanella
61d848b554 elf: Ignore LD_BIND_NOW and LD_BIND_NOT for setuid binaries
To avoid any environment variable to change setuid binaries
semantics.

Checked on x86_64-linux-gnu.
Reviewed-by: Siddhesh Poyarekar <siddhesh@sourceware.org>
2023-12-05 13:21:36 -03:00
Adhemerval Zanella
876a12e513 elf: Ignore loader debug env vars for setuid
Loader already ignores LD_DEBUG, LD_DEBUG_OUTPUT, and
LD_TRACE_LOADED_OBJECTS. Both LD_WARN and LD_VERBOSE are similar to
LD_DEBUG, in the sense they enable additional checks and debug
information, so it makes sense to disable them.

Also add both LD_VERBOSE and LD_WARN on filtered environment variables
for setuid binaries.

Checked on x86_64-linux-gnu.
Reviewed-by: Siddhesh Poyarekar <siddhesh@sourceware.org>
2023-12-05 13:21:36 -03:00
Joseph Myers
2e0c0ff95c Remove __access_noerrno
A recent commit, apparently commit
6c6fce572f "elf: Remove /etc/suid-debug
support", resulted in localplt failures for i686-gnu and x86_64-gnu:

Missing required PLT reference: ld.so: __access_noerrno

After that commit, __access_noerrno is actually no longer used at all.
So rather than just removing the localplt expectation for that symbol
for Hurd, completely remove all definitions of and references to that
symbol.

Tested for x86_64, and with build-many-glibcs.py for i686-gnu and
x86_64-gnu.
2023-11-23 19:01:32 +00:00
Adhemerval Zanella
11f7e3dd8f elf: Add all malloc tunable to unsecvars
Some environment variables allow alteration of allocator behavior
across setuid boundaries, where a setuid program may ignore the
tunable, but its non-setuid child can read it and adjust the memory
allocator behavior accordingly.

Most library behavior tunings is limited to the current process and does
not bleed in scope; so it is unclear how pratical this misfeature is.
If behavior change across privilege boundaries is desirable, it would be
better done with a wrapper program around the non-setuid child that sets
these envvars, instead of using the setuid process as the messenger.

The patch as fixes tst-env-setuid, where it fail if any unsecvars is
set.  It also adds a dynamic test, although it requires
--enable-hardcoded-path-in-tests so kernel correctly sets the setuid
bit (using the loader command directly would require to set the
setuid bit on the loader itself, which is not a usual deployment).

Co-authored-by: Siddhesh Poyarekar <siddhesh@sourceware.org>

Checked on x86_64-linux-gnu.
Reviewed-by: DJ Delorie <dj@redhat.com>
2023-11-21 16:15:42 -03:00
Adhemerval Zanella
a72a4eb10b elf: Add GLIBC_TUNABLES to unsecvars
setuid/setgid process now ignores any glibc tunables, and filters out
all environment variables that might changes its behavior. This patch
also adds GLIBC_TUNABLES, so any spawned process by setuid/setgid
processes should set tunable explicitly.

Checked on x86_64-linux-gnu.

Reviewed-by: Florian Weimer <fweimer@redhat.com>
Reviewed-by: Siddhesh Poyarekar <siddhesh@sourceware.org>
2023-11-21 16:15:42 -03:00
Adhemerval Zanella
78ed8bdf4f linux: Add PR_SET_VMA_ANON_NAME support
Linux 5.17 added support to naming anonymous virtual memory areas
through the prctl syscall.  The __set_vma_name is a wrapper to avoid
optimizing the prctl call if the kernel does not support it.

If the kernel does not support PR_SET_VMA_ANON_NAME, prctl returns
EINVAL. And it also returns the same error for an invalid argument.
Since it is an internal-only API, it assumes well-formatted input:
aligned START, with (START, START+LEN) being a valid memory range,
and NAME with a limit of 80 characters without an invalid one
("\\`$[]").
Reviewed-by: DJ Delorie <dj@redhat.com>
2023-11-07 10:27:20 -03:00
Adhemerval Zanella
fccf38c517 string: Add internal memswap implementation
The prototype is:

  void __memswap (void *restrict p1, void *restrict p2, size_t n)

The function swaps the content of two memory blocks P1 and P2 of
len N.  Memory overlap is NOT handled.

It will be used on qsort optimization.

Checked on x86_64-linux-gnu and aarch64-linux-gnu.
Reviewed-by: Noah Goldstein <goldstein.w.n@gmail.com>
2023-10-31 14:17:33 -03:00
Adhemerval Zanella
e6e3c66688 crypt: Remove libcrypt support
All the crypt related functions, cryptographic algorithms, and
make requirements are removed,  with only the exception of md5
implementation which is moved to locale folder since it is
required by localedef for integrity protection (libc's
locale-reading code does not check these, but localedef does
generate them).

Besides thec code itself, both internal documentation and the
manual is also adjusted.  This allows to remove both --enable-crypt
and --enable-nss-crypt configure options.

Checked with a build for all affected ABIs.

Co-authored-by: Zack Weinberg <zack@owlfolio.org>
Reviewed-by: Carlos O'Donell <carlos@redhat.com>
2023-10-30 13:03:59 -03:00
Florian Weimer
dd32e1db38 Revert "elf: Always call destructors in reverse constructor order (bug 30785)"
This reverts commit 6985865bc3.

Reason for revert:

The commit changes the order of ELF destructor calls too much relative
to what applications expect or can handle.  In particular, during
process exit and _dl_fini, after the revert commit, we no longer call
the destructors of the main program first; that only happens after
some dlopen'ed objects have been destructed.  This robs applications
of an opportunity to influence destructor order by calling dlclose
explicitly from the main program's ELF destructors.  A couple of
different approaches involving reverse constructor order were tried,
and none of them worked really well.  It seems we need to keep the
dependency sorting in _dl_fini.

There is also an ambiguity regarding nested dlopen calls from ELF
constructors: Should those destructors run before or after the object
that called dlopen?  Commit 6985865bc3 used reverse order
of the start of ELF constructor calls for destructors, but arguably
using completion of constructors is more correct.  However, that alone
is not sufficient to address application compatibility issues (it
does not change _dl_fini ordering at all).
2023-10-18 11:30:38 +02:00
Bruno Victal
3333eb55b7 Add LE DSCP code point from RFC-8622.
Signed-off-by: Bruno Victal <mirai@makinata.eu>
Reviewed-by: Florian Weimer <fweimer@redhat.com>
2023-10-17 19:00:27 +02:00
Siddhesh Poyarekar
0d5f9ea97f Propagate GLIBC_TUNABLES in setxid binaries
GLIBC_TUNABLES scrubbing happens earlier than envvar scrubbing and some
tunables are required to propagate past setxid boundary, like their
env_alias.  Rely on tunable scrubbing to clean out GLIBC_TUNABLES like
before, restoring behaviour in glibc 2.37 and earlier.

Signed-off-by: Siddhesh Poyarekar <siddhesh@sourceware.org>
Reviewed-by: Carlos O'Donell <carlos@redhat.com>
2023-10-02 15:35:05 -04:00
Florian Weimer
f563971b5b elf: Add dummy declaration of _dl_audit_objclose for !SHARED
This allows us to avoid some #ifdef SHARED conditionals.

Reviewed-by: Carlos O'Donell <carlos@redhat.com>
2023-09-26 11:40:12 +02:00
Florian Weimer
6985865bc3 elf: Always call destructors in reverse constructor order (bug 30785)
The current implementation of dlclose (and process exit) re-sorts the
link maps before calling ELF destructors.  Destructor order is not the
reverse of the constructor order as a result: The second sort takes
relocation dependencies into account, and other differences can result
from ambiguous inputs, such as cycles.  (The force_first handling in
_dl_sort_maps is not effective for dlclose.)  After the changes in
this commit, there is still a required difference due to
dlopen/dlclose ordering by the application, but the previous
discrepancies went beyond that.

A new global (namespace-spanning) list of link maps,
_dl_init_called_list, is updated right before ELF constructors are
called from _dl_init.

In dl_close_worker, the maps variable, an on-stack variable length
array, is eliminated.  (VLAs are problematic, and dlclose should not
call malloc because it cannot readily deal with malloc failure.)
Marking still-used objects uses the namespace list directly, with
next and next_idx replacing the done_index variable.

After marking, _dl_init_called_list is used to call the destructors
of now-unused maps in reverse destructor order.  These destructors
can call dlopen.  Previously, new objects do not have l_map_used set.
This had to change: There is no copy of the link map list anymore,
so processing would cover newly opened (and unmarked) mappings,
unloading them.  Now, _dl_init (indirectly) sets l_map_used, too.
(dlclose is handled by the existing reentrancy guard.)

After _dl_init_called_list traversal, two more loops follow.  The
processing order changes to the original link map order in the
namespace.  Previously, dependency order was used.  The difference
should not matter because relocation dependencies could already
reorder link maps in the old code.

The changes to _dl_fini remove the sorting step and replace it with
a traversal of _dl_init_called_list.  The l_direct_opencount
decrement outside the loader lock is removed because it appears
incorrect: the counter manipulation could race with other dynamic
loader operations.

tst-audit23 needs adjustments to the changes in LA_ACT_DELETE
notifications.  The new approach for checking la_activity should
make it clearer that la_activty calls come in pairs around namespace
updates.

The dependency sorting test cases need updates because the destructor
order is always the opposite order of constructor order, even with
relocation dependencies or cycles present.

There is a future cleanup opportunity to remove the now-constant
force_first and for_fini arguments from the _dl_sort_maps function.

Fixes commit 1df71d32fe ("elf: Implement
force_first handling in _dl_sort_maps_dfs (bug 28937)").

Reviewed-by: DJ Delorie <dj@redhat.com>
2023-09-08 12:34:27 +02:00
Szabolcs Nagy
d2123d6827 elf: Fix slow tls access after dlopen [BZ #19924]
In short: __tls_get_addr checks the global generation counter and if
the current dtv is older then _dl_update_slotinfo updates dtv up to the
generation of the accessed module. So if the global generation is newer
than generation of the module then __tls_get_addr keeps hitting the
slow dtv update path. The dtv update path includes a number of checks
to see if any update is needed and this already causes measurable tls
access slow down after dlopen.

It may be possible to detect up-to-date dtv faster.  But if there are
many modules loaded (> TLS_SLOTINFO_SURPLUS) then this requires at
least walking the slotinfo list.

This patch tries to update the dtv to the global generation instead, so
after a dlopen the tls access slow path is only hit once.  The modules
with larger generation than the accessed one were not necessarily
synchronized before, so additional synchronization is needed.

This patch uses acquire/release synchronization when accessing the
generation counter.

Note: in the x86_64 version of dl-tls.c the generation is only loaded
once, since relaxed mo is not faster than acquire mo load.

I have not benchmarked this. Tested by Adhemerval Zanella on aarch64,
powerpc, sparc, x86 who reported that it fixes the performance issue
of bug 19924.

Reviewed-by: Adhemerval Zanella  <adhemerval.zanella@linaro.org>
2023-09-01 08:21:37 +01:00
Adhemerval Zanella
dddc88587a sparc: Fix la_symbind for bind-now (BZ 23734)
The sparc ABI has multiple cases on how to handle JMP_SLOT relocations,
(sparc_fixup_plt/sparc64_fixup_plt).  For BINDNOW, _dl_audit_symbind
will be responsible to setup the final relocation value; while for
lazy binding _dl_fixup/_dl_profile_fixup will call the audit callback
and tail cail elf_machine_fixup_plt (which will call
sparc64_fixup_plt).

This patch fixes by issuing the SPARC specific routine on bindnow and
forwarding the audit value to elf_machine_fixup_plt for lazy resolution.
It fixes the la_symbind for bind-now tests on sparc64 and sparcv9:

  elf/tst-audit24a
  elf/tst-audit24b
  elf/tst-audit24c
  elf/tst-audit24d

Checked on sparc64-linux-gnu and sparcv9-linux-gnu.
Tested-by: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>
2023-07-12 15:29:08 -03:00
Joe Ramsay
aed39a3aa3 aarch64: Add vector implementations of cos routines
Replace the loop-over-scalar placeholder routines with optimised
implementations from Arm Optimized Routines (AOR).

Also add some headers containing utilities for aarch64 libmvec
routines, and update libm-test-ulps.

Data tables for new routines are used via a pointer with a
barrier on it, in order to prevent overly aggressive constant
inlining in GCC. This allows a single adrp, combined with offset
loads, to be used for every constant in the table.

Special-case handlers are marked NOINLINE in order to confine the
save/restore overhead of switching from vector to normal calling
standard. This way we only incur the extra memory access in the
exceptional cases. NOINLINE definitions have been moved to
math_private.h in order to reduce duplication.

AOR exposes a config option, WANT_SIMD_EXCEPT, to enable
selective masking (and later fixing up) of invalid lanes, in
order to trigger fp exceptions correctly (AdvSIMD only). This is
tested and maintained in AOR, however it is configured off at
source level here for performance reasons. We keep the
WANT_SIMD_EXCEPT blocks in routine sources to greatly simplify
the upstreaming process from AOR to glibc.

Reviewed-by: Szabolcs Nagy <szabolcs.nagy@arm.com>
2023-06-30 09:04:10 +01:00
Paul Pluzhnikov
65cc53fe7c Fix misspellings in sysdeps/ -- BZ 25337 2023-05-30 23:02:29 +00:00
Ronan Pigott
8f59fc79b7 Add voice-admit DSCP code point from RFC-5865 2023-05-22 22:13:41 +02:00
Sergey Bugaev
4644fb9c4c elf: Stop including tls.h in ldsodefs.h
Nothing in there needs tls.h

Signed-off-by: Sergey Bugaev <bugaevc@gmail.com>
Message-Id: <20230319151017.531737-24-bugaevc@gmail.com>
2023-04-10 23:26:28 +02:00
Adhemerval Zanella Netto
33237fe83d Remove --enable-tunables configure option
And make always supported.  The configure option was added on glibc 2.25
and some features require it (such as hwcap mask, huge pages support, and
lock elisition tuning).  It also simplifies the build permutations.

Changes from v1:
 * Remove glibc.rtld.dynamic_sort changes, it is orthogonal and needs
   more discussion.
 * Cleanup more code.
Reviewed-by: Siddhesh Poyarekar <siddhesh@sourceware.org>
2023-03-29 14:33:06 -03:00
Adhemerval Zanella Netto
88677348b4 Move libc_freeres_ptrs and libc_subfreeres to hidden/weak functions
They are both used by __libc_freeres to free all library malloc
allocated resources to help tooling like mtrace or valgrind with
memory leak tracking.

The current scheme uses assembly markers and linker script entries
to consolidate the free routine function pointers in the RELRO segment
and to be freed buffers in BSS.

This patch changes it to use specific free functions for
libc_freeres_ptrs buffers and call the function pointer array directly
with call_function_static_weak.

It allows the removal of both the internal macros and the linker
script sections.

Checked on x86_64-linux-gnu, i686-linux-gnu, and aarch64-linux-gnu.
Reviewed-by: Carlos O'Donell <carlos@redhat.com>
2023-03-27 13:57:55 -03:00
caiyinyu
f0d33cbdce LoongArch: Add support for ldconfig. 2023-03-13 09:20:28 +08:00
Joan Bruguera
1b0ea8c5d8 elf: Restore ldconfig libc6 implicit soname logic [BZ #30125]
While cleaning up old libc version support, the deprecated libc4 code was
accidentally kept in `implicit_soname`, instead of the libc6 code.

This causes additional symlinks to be created by `ldconfig` for libraries
without a soname, e.g. a library `libsomething.123.456.789` without a soname
will create a `libsomething.123` -> `libsomething.123.456.789` symlink.

As the libc6 version of the `implicit_soname` code is a trivial `xstrdup`,
just inline it and remove `implicit_soname` altogether.

Some further simplification looks possible (e.g. the call to `create_links`
looks like a no-op if `soname == NULL`, other than the verbose printfs), but
logic is kept as-is for now.

Fixes: BZ #30125
Fixes: 8ee878592c ("Assume only FLAG_ELF_LIBC6 suport")
Signed-off-by: Joan Bruguera <joanbrugueram@gmail.com>

Reviewed-by: Adhemerval Zanella  <adhemerval.zanella@linaro.org>
2023-02-20 09:32:46 -03:00
Adhemerval Zanella
a9b3b770f5 string: Remove string_private.h
Now that _STRING_ARCH_unaligned is not used anymore.

Reviewed-by: Wilco Dijkstra  <Wilco.Dijkstra@arm.com>
2023-02-17 15:56:54 -03:00
Samuel Thibault
8420b3e832 Fix typos in comments 2023-02-12 16:34:28 +01:00
Adhemerval Zanella
00cb84dde7 Add string vectorized find and detection functions
This patch adds generic string find and detection meant to be used in
generic vectorized string implementation.  The idea is to decompose the
basic string operation so each architecture can reimplement if it
provides any specialized hardware instruction.

The 'string-misc.h' provides miscellaneous functions:

  - extractbyte: extracts the byte from an specific index.
  - repeat_bytes: setup an word by replicate the argument on each byte.

The 'string-fza.h' provides zero byte detection functions:

  - find_zero_low, find_zero_all, find_eq_low, find_eq_all,
    find_zero_eq_low, find_zero_eq_all, and find_zero_ne_all

The 'string-fzb.h' provides boolean zero byte detection functions:

  - has_zero: determine if any byte within a word is zero.
  - has_eq: determine byte equality between two words.
  - has_zero_eq: determine if any byte within a word is zero along with
    byte equality between two words.

The 'string-fzi.h' provides positions for string-fza.h results:

  - index_first: return index of first zero byte within a word.
  - index_last: return index of first byte different between two words.

The 'string-fzc.h' provides a combined version of fza and fzi:

  - index_first_zero_eq: return index of first zero byte within a word or
    first byte different between two words.
  - index_first_zero_ne: return index of first zero byte within a word or
    first byte equal between two words.
  - index_last_zero: return index of last zero byte within a word.
  - index_last_eq: return index of last byte different between two words.

The 'string-shift.h' provides a way to mask off parts of a work based on
some alignmnet (to handle unaligned arguments):

  - shift_find, shift_find_last.

Co-authored-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Noah Goldstein <goldstein.w.n@gmail.com>
2023-02-06 16:19:35 -03:00
Richard Henderson
d45890b28c Parameterize OP_T_THRES from memcopy.h
It moves OP_T_THRES out of memcopy.h to its own header and adjust
each architecture that redefines it.

Checked with a build and check with run-built-tests=no for all major
Linux ABIs.

Co-authored-by: Adhemerval Zanella  <adhemerval.zanella@linaro.org>
Reviewed-by: Carlos O'Donell <carlos@redhat.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
2023-02-06 16:19:35 -03:00
Adhemerval Zanella
d1a9b6d8e7 Parameterize op_t from memcopy.h
It moves the op_t definition out to an specific header, adds
the attribute 'may-alias', and cleanup its duplicated definitions.

Checked with a build and check with run-built-tests=no for all major
Linux ABIs.

Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
2023-02-06 16:19:35 -03:00
Joseph Myers
6d7e8eda9b Update copyright dates with scripts/update-copyrights 2023-01-06 21:14:39 +00:00
Xiaolin Tang
2e2485ce05 Use GCC builtins for logb functions if desired.
This patch is using the corresponding GCC builtin for logbf, logb,
logbl and logbf128 if the USE_FUNCTION_BUILTIN macros are defined to one
in math-use-builtins-function.h.

Co-Authored-By: Xi Ruoyao <xry111@xry111.site>
2022-11-29 16:00:28 +08:00
Xiaolin Tang
a1981ecbfd Use GCC builtins for llrint functions if desired.
This patch is using the corresponding GCC builtin for llrintf, llrint,
llrintl and llrintf128 if the USE_FUNCTION_BUILTIN macros are defined to one
in math-use-builtins-function.h.

Co-Authored-By: Xi Ruoyao <xry111@xry111.site>
2022-11-29 16:00:28 +08:00
Xiaolin Tang
2b23ab1fea Use GCC builtins for lrint functions if desired.
This patch is using the corresponding GCC builtin for lrintf, lrint,
lrintl and lrintf128 if the USE_FUNCTION_BUILTIN macros are defined to one
in math-use-builtins-function.h.

Co-Authored-By: Xi Ruoyao <xry111@xry111.site>
2022-11-29 16:00:28 +08:00
Florian Weimer
1f34a23288 elf: Introduce <dl-call_tls_init_tp.h> and call_tls_init_tp (bug 29249)
This makes it more likely that the compiler can compute the strlen
argument in _startup_fatal at compile time, which is required to
avoid a dependency on strlen this early during process startup.

Reviewed-by: Szabolcs Nagy <szabolcs.nagy@arm.com>
2022-11-03 17:28:03 +01:00
Florian Weimer
ee1ada1bdb elf: Rework exception handling in the dynamic loader [BZ #25486]
The old exception handling implementation used function interposition
to replace the dynamic loader implementation (no TLS support) with the
libc implementation (TLS support).  This results in problems if the
link order between the dynamic loader and libc is reversed (bug 25486).

The new implementation moves the entire implementation of the
exception handling functions back into the dynamic loader, using
THREAD_GETMEM and THREAD_SETMEM for thread-local data support.
These depends on Hurd support for these macros, added in commit
b65a82e4e7 ("hurd: Add THREAD_GET/SETMEM/_NC").

One small obstacle is that the exception handling facilities are used
before the TCB has been set up, so a check is needed if the TCB is
available.  If not, a regular global variable is used to store the
exception handling information.

Also rename dl-error.c to dl-catch.c, to avoid confusion with the
dlerror function.

Reviewed-by: Siddhesh Poyarekar <siddhesh@sourceware.org>
2022-11-03 09:39:31 +01:00
Letu Ren
0cc0033ef1 stdlib/strfrom: Add copysign to fix NAN issue on riscv (BZ #29501)
According to the specification of ISO/IEC TS 18661-1:2014,

The strfromd, strfromf, and strfroml functions are equivalent to
snprintf(s, n, format, fp) (7.21.6.5), except the format string contains only
the character %, an optional precision that does not contain an asterisk *, and
one of the conversion specifiers a, A, e, E, f, F, g, or G, which applies to
the type (double, float, or long double) indicated by the function suffix
(rather than  by a length modifier). Use of these functions with any other 20
format string results in undefined behavior.

strfromf will convert the arguement with type float to double first.

According to the latest version of IEEE754 which is published in 2019,

Conversion of a quiet NaN from a narrower format to a wider format in the same
radix, and then back to the same narrower format, should not change the quiet
NaN payload in any way except to make it canonical.

When either an input or result is a NaN, this standard does not interpret the
sign of a NaN. However, operations on bit strings—copy, negate, abs,
copySign—specify the sign bit of a NaN result, sometimes based upon the sign
bit of a NaN operand. The logical predicates totalOrder and isSignMinus are
also affected by the sign bit of a NaN operand. For all other operations, this
standard does not specify the sign bit of a NaN result, even when there is only
one input NaN, or when the NaN is produced from an invalid operation.

converting NAN or -NAN with type float to double doesn't need to keep
the signbit. As a result, this test case isn't mandatory.

The problem is that according to RISC-V ISA manual in chapter 11.3 of
riscv-isa-20191213,

Except when otherwise stated, if the result of a floating-point operation is
NaN, it is the canonical NaN. The canonical NaN has a positive sign and all
significand bits clear except the MSB, a.k.a. the quiet bit. For
single-precision floating-point, this corresponds to the pattern 0x7fc00000.

which means that conversion -NAN from float to double won't keep the signbit.

Since glibc ought to be consistent here between types and architectures, this
patch adds copysign to fix this problem if the string is NAN. This patch
adds two different functions under sysdeps directory to work around the
issue.

This patch has been tested on x86_64 and riscv64.

Resolves: BZ #29501

v2: Change from macros to different inline functions.
v3: Add unlikely check to isnan.
v4: Fix wrong commit message header.
v5: Fix style: add space before parentheses.
v6: Add copyright.
Signed-off-by: Letu Ren <fantasquex@gmail.com>
Reviewed-by: Adhemerval Zanella  <adhemerval.zanella@linaro.org>
2022-10-28 11:35:20 -03:00
Florian Weimer
6f360366f7 elf: Introduce to _dl_call_fini
This consolidates the destructor invocations from _dl_fini and
dlclose.  Remove the micro-optimization that avoids
calling _dl_call_fini if they are no destructors (as dlclose is quite
expensive anyway).  The debug log message is now printed
unconditionally.

Reviewed-by: Adhemerval Zanella  <adhemerval.zanella@linaro.org>
2022-10-27 11:36:44 +02:00
Florian Weimer
a65ff76c9a ld.so: Export tls_init_tp_called as __rtld_tls_init_tp_called
This allows the rest of dynamic loader to check whether the TCB
has been set up (and THREAD_GETMEM and THREAD_SETMEM will work).

Reviewed-by: Siddhesh Poyarekar <siddhesh@gotplt.org>
2022-10-27 11:36:44 +02:00
Florian Weimer
58548b9d68 Use PTR_MANGLE and PTR_DEMANGLE unconditionally in C sources
In the future, this will result in a compilation failure if the
macros are unexpectedly undefined (due to header inclusion ordering
or header inclusion missing altogether).

Assembler sources are more difficult to convert.  In many cases,
they are hand-optimized for the mangling and no-mangling variants,
which is why they are not converted.

sysdeps/s390/s390-32/__longjmp.c and sysdeps/s390/s390-64/__longjmp.c
are special: These are C sources, but most of the implementation is
in assembler, so the PTR_DEMANGLE macro has to be undefined in some
cases, to match the assembler style.

Reviewed-by: Adhemerval Zanella  <adhemerval.zanella@linaro.org>
2022-10-18 17:04:10 +02:00
Florian Weimer
88f4b6929c Introduce <pointer_guard.h>, extracted from <sysdep.h>
This allows us to define a generic no-op version of PTR_MANGLE and
PTR_DEMANGLE.  In the future, we can use PTR_MANGLE and PTR_DEMANGLE
unconditionally in C sources, avoiding an unintended loss of hardening
due to missing include files or unlucky header inclusion ordering.

In i386 and x86_64, we can avoid a <tls.h> dependency in the C
code by using the computed constant from <tcb-offsets.h>.  <sysdep.h>
no longer includes these definitions, so there is no cyclic dependency
anymore when computing the <tcb-offsets.h> constants.

Reviewed-by: Adhemerval Zanella  <adhemerval.zanella@linaro.org>
2022-10-18 17:03:55 +02:00
Adhemerval Zanella
5355f9ca7b elf: Remove -fno-tree-loop-distribute-patterns usage on dl-support
Besides the option being gcc specific, this approach is still fragile
and not future proof since we do not know if this will be the only
optimization option gcc will add that transforms loops to memset
(or any libcall).

This patch adds a new header, dl-symbol-redir-ifunc.h, that can b
used to redirect the compiler generated libcalls to port the generic
memset implementation if required.

Checked on x86_64-linux-gnu and aarch64-linux-gnu.
Reviewed-by: Carlos O'Donell <carlos@redhat.com>
2022-10-10 10:32:28 -03:00
Javier Pello
ab40f20364 elf: Remove _dl_string_hwcap
Removal of legacy hwcaps support from the dynamic loader left
no users of _dl_string_hwcap.

Signed-off-by: Javier Pello <devel@otheo.eu>
Reviewed-by: Adhemerval Zanella  <adhemerval.zanella@linaro.org>
2022-10-06 07:59:48 -03:00
Javier Pello
4a7094119c elf: Remove hwcap parameter from add_to_cache signature
Last commit made it so that the value passed for that parameter was
always 0 at its only call site.

Signed-off-by: Javier Pello <devel@otheo.eu>
Reviewed-by: Florian Weimer <fweimer@redhat.com>
2022-10-06 07:59:48 -03:00
Adhemerval Zanella
aeb4d2e981 m68k: Enforce 4-byte alignment on internal locks (BZ #29537)
A new internal definition, __LIBC_LOCK_ALIGNMENT, is used to force
the 4-byte alignment only for m68k, other architecture keep the
natural alignment of the type used internally (and hppa does not
require 16-byte alignment for kernel-assisted CAS).

Reviewed-by: Florian Weimer <fweimer@redhat.com>
2022-09-20 10:56:54 -03:00
Florian Weimer
dbb75513f5 elf: Rename _dl_sort_maps parameter from skip to force_first
The new implementation will not be able to skip an arbitrary number
of objects.

Reviewed-by: Adhemerval Zanella  <adhemerval.zanella@linaro.org>
2022-09-06 07:38:33 +02:00