Commit Graph

6352 Commits

Author SHA1 Message Date
H.J. Lu
5adb0e14a5 i386: Add the clone3 wrapper
extern int clone3 (struct clone_args *__cl_args, size_t __size,
		   int (*__func) (void *__arg), void *__arg);

Reviewed-by: Carlos O'Donell <carlos@redhat.com>
2021-07-19 07:36:19 -07:00
Florian Weimer
ea9878ec27 resolv: Move res_query functions into libc
This switches to public symbols without __ prefixes, due to improved
namespace management in glibc.

The script was used with --no-new-version to move the symbols
__res_nquery, __res_nquerydomain, __res_nsearch, __res_query,
__res_querydomain, __res_search, res_query, res_querydomain,
res_search.  The public symbols res_nquery, res_nquerydomain,
res_nsearch, res_ownok, res_query, res_querydomain, res_search
were added with make update-all-abi.

Reviewed-by: Carlos O'Donell <carlos@redhat.com>
Tested-by: Carlos O'Donell <carlos@redhat.com>
2021-07-19 07:56:57 +02:00
Florian Weimer
21a497cc58 resolv: Move res_mkquery, res_nmkquery into libc
This switches to public symbols without __ prefixes, due to improved
namespace management in glibc.

The symbols res_mkquery, __res_mkquery, __res_nmkquery were
moved with the script (using --no-new-version).
res_mkquery@@GLIBC_2.34, res_nmkquery@@GLIBC_2.34 were added using
make update-all-abi.

Reviewed-by: Carlos O'Donell <carlos@redhat.com>
Tested-by: Carlos O'Donell <carlos@redhat.com>
2021-07-19 07:56:57 +02:00
Florian Weimer
b165c65c35 resolv: Move res_send, res_nsend into libc
Switch to public symbols without __ prefix (due to improved
namespace management).

__res_send, __res_nsend were moved using the script (with
--no-new-version).  res_send@@GLIBC_2.34 and res_nsend@@GLIBC_2.34
were added using make update-all-abi.

Reviewed-by: Carlos O'Donell <carlos@redhat.com>
2021-07-19 07:56:45 +02:00
Florian Weimer
2fbe5860d3 resolv: Rename res_comp.c to res-name-checking.c and move into libc
This reflects what the remaining functions in the file do.

The __res_dnok, __res_hnok, __res_mailok, __res_ownok were moved
with the script, using --no-new-version, and turned into compat
symbols.  __libc_res_dnok@@GLIBC_PRIVATE and
__libc_res_hnok@@GLIBC_PRIVATE are added for internal use, to avoid
accidentally binding to compatibility symbols.  The new public
symbols res_dnok, res_hnok, res_mailok, res_ownok were added using
make update-all-abi.

Reviewed-by: Carlos O'Donell <carlos@redhat.com>
Tested-by: Carlos O'Donell <carlos@redhat.com>
2021-07-19 07:56:21 +02:00
Florian Weimer
391e02236b resolv: Move dn_skipname to its own file and into libc
And reformat it to GNU style.

dn_skipname is used outside glibc, so do not deprecate it,
and export it as dn_skipname (not __dn_skipname).  Due to internal
users, provide a __libc_dn_skipname alias, and keep __dn_skipname
as a pure compatibility symbol.

__dn_skipname@GLIBC_2.0 was moved using the script, and
dn_skipname@@GLIBC_2.34 was added using make update-all-abi.

Reviewed-by: Carlos O'Donell <carlos@redhat.com>
Tested-by: Carlos O'Donell <carlos@redhat.com>
2021-07-19 07:56:21 +02:00
Florian Weimer
fd8a87c0c1 resolv: Move dn_comp to its own file and into libc
And reformat it to GNU style.

dn_comp is used in various programs, so keep it as a non-deprecated
symbol.  Switch to dn_comp (not __dn_comp) for the ABI name.  There
are no internal users, so interposition is not a problem.

The __dn_comp symbol was moved with scripts/move-symbol-to-libc.py
--no-new-version.  dn_comp@@GLIBC_2.34 was added with
make update-all-abi.

Reviewed-by: Carlos O'Donell <carlos@redhat.com>
Tested-by: Carlos O'Donell <carlos@redhat.com>
2021-07-19 07:56:21 +02:00
Florian Weimer
640bbdf71c resolv: Move dn_expand to its own file and into libc
And reformat to GNU style.

This switches back to the dn_expand name for the ABI symbol and turns
__dn_expand into a compatibility symbol.  With the improved namespace
management in current glibc, it is no longer necessary to use a
private namespace symbol.  To avoid old code binding to a
GLIBC_PRIVATE symbol by accident, use __libc_dn_expand for the
internal symbol name.

The symbols dn_expand, __dnexpand were moved using
scripts/move-symbol-to-libc.py, followed by an adjustment to make
dn_expand the only GLIBC_2.34 symbol.

Reviewed-by: Carlos O'Donell <carlos@redhat.com>
Tested-by: Carlos O'Donell <carlos@redhat.com>
2021-07-19 07:56:21 +02:00
Florian Weimer
13e1f86706 resolv: Move ns_name_compress into its own file and into libc
And reformat to GNU style.

The symbol was moved using scripts/move-symbol-to-libc.py.

Reviewed-by: Carlos O'Donell <carlos@redhat.com>
Tested-by: Carlos O'Donell <carlos@redhat.com>
2021-07-19 07:56:21 +02:00
Florian Weimer
7ed1ac6da3 resolv: Move ns_name_pack into its own file and into libc
And reformat to GNU style, and eliminate the labellen function.

The symbol was moved using scripts/move-symbol-to-libc.py.

Reviewed-by: Carlos O'Donell <carlos@redhat.com>
Tested-by: Carlos O'Donell <carlos@redhat.com>
2021-07-19 07:56:21 +02:00
Florian Weimer
276e9822b3 resolv: Move ns_name_pton into its own file and into libc
And reformat to GNU style, and eliminate the digits variable.

The symbol was moved using scripts/move-symbol-to-libc.py.

Reviewed-by: Carlos O'Donell <carlos@redhat.com>
Tested-by: Carlos O'Donell <carlos@redhat.com>
2021-07-19 07:56:21 +02:00
Florian Weimer
4e1d3db1e8 resolv: Move ns_name_uncompress into its own file and into libc
And reformat to GNU style.  Check for negative error returns
(instead of -1).

The symbol was moved using scripts/move-symbol-to-libc.py.

Reviewed-by: Carlos O'Donell <carlos@redhat.com>
Tested-by: Carlos O'Donell <carlos@redhat.com>
2021-07-19 07:56:21 +02:00
Florian Weimer
cff2c78c51 resolv: Move ns_name_skip to its own file and into libc (bug 28091)
And reformat to GNU style.  Avoid out-of-bounds pointer arithmetic.
This also results in a fix of bug 28091 due to the additional packet
length checks.

The symbol was moved using scripts/move-symbol-to-libc.py.

Reviewed-by: Carlos O'Donell <carlos@systemhalted.org>
2021-07-19 07:56:13 +02:00
Florian Weimer
820bb23ff0 resolv: Move ns_name_unpack to its own file and into libc
Reformat to GNU style. Avoid out-of-bounds buffer arithmetic.
Eliminate the labellen function.

The symbol was moved using scripts/move-symbol-to-libc.py.

Reviewed-by: Carlos O'Donell <carlos@redhat.com>
Tested-by: Carlos O'Donell <carlos@redhat.com>
2021-07-15 09:00:27 +02:00
Florian Weimer
adcc572a29 resolv: Move ns_name_ntop to its own file and into libc
Reformat to GNU style.  Avoid out-of-bounds pointer arithmetic
(e.g., use eom - dn < 2 instead of dn + 1 >= eom).  Inline the
labellen function and fold the compression pointer check into
the length check (l >= 64).  Assume ASCII encoding.

The symbol was moved using scripts/move-symbol-to-libc.py.

Reviewed-by: Carlos O'Donell <carlos@redhat.com>
Tested-by: Carlos O'Donell <carlos@redhat.com>
2021-07-15 08:39:31 +02:00
Florian Weimer
b8f889064d socket: Add hidden prototype for setsockopt
Reviewed-by: Adhemerval Zanella  <adhemerval.zanella@linaro.org>
Reviewed-by: Carlos O'Donell <carlos@redhat.com>
Tested-by: Carlos O'Donell <carlos@redhat.com>
2021-07-15 08:35:45 +02:00
H.J. Lu
84d40d702f Add static tests for __clone_internal
Reviewed-by: Adhemerval Zanella  <adhemerval.zanella@linaro.org>
2021-07-14 06:55:04 -07:00
H.J. Lu
24c78e2c75 x86-64: Add the clone3 wrapper
extern int clone3 (struct clone_args *__cl_args, size_t __size,
		   int (*__func) (void *__arg), void *__arg);

Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
2021-07-14 06:34:13 -07:00
H.J. Lu
d8ea0d0168 Add an internal wrapper for clone, clone2 and clone3
The clone3 system call (since Linux 5.3) provides a superset of the
functionality of clone and clone2.  It also provides a number of API
improvements, including the ability to specify the size of the child's
stack area which can be used by kernel to compute the shadow stack size
when allocating the shadow stack.  Add:

extern int __clone_internal (struct clone_args *__cl_args,
			     int (*__func) (void *__arg), void *__arg);

to provide an abstract interface for clone, clone2 and clone3.

1. Simplify stack management for thread creation by passing both stack
base and size to create_thread.
2. Consolidate clone vs clone2 differences into a single file.
3. Call __clone3 if HAVE_CLONE3_WAPPER is defined.  If __clone3 returns
-1 with ENOSYS, fall back to clone or clone2.
4. Use only __clone_internal to clone a thread.  Since the stack size
argument for create_thread is now unconditional, always pass stack size
to create_thread.
5. Enable the public clone3 wrapper in the future after it has been
added to all targets.

NB: Sandbox will return ENOSYS on clone3 in both Chromium:

The following revision refers to this bug:
  218438259d

commit 218438259dd795456f0a48f67cbe5b4e520db88b
Author: Matthew Denton <mpdenton@chromium.org>
Date: Thu Jun 03 20:06:13 2021

Linux sandbox: return ENOSYS for clone3

Because clone3 uses a pointer argument rather than a flags argument, we
cannot examine the contents with seccomp, which is essential to
preventing sandboxed processes from starting other processes. So, we
won't be able to support clone3 in Chromium. This CL modifies the
BPF policy to return ENOSYS for clone3 so glibc always uses the fallback
to clone.

Bug: 1213452
Change-Id: I7c7c585a319e0264eac5b1ebee1a45be2d782303
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2936184
Reviewed-by: Robert Sesek <rsesek@chromium.org>
Commit-Queue: Matthew Denton <mpdenton@chromium.org>
Cr-Commit-Position: refs/heads/master@{#888980}

[modify] https://crrev.com/218438259dd795456f0a48f67cbe5b4e520db88b/sandbox/linux/seccomp-bpf-helpers/baseline_policy.cc

and Firefox:

https://hg.mozilla.org/integration/autoland/rev/ecb4011a0c76

Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
2021-07-14 06:33:58 -07:00
Adhemerval Zanella
72e84d1db2 Linux: Use 32-bit vDSO for clock_gettime, gettimeofday, time (BZ# 28071)
The previous approach defeats the vDSO optimization on older kernels
because a failing clock_gettime64 system call is performed on every
function call.  It also results in a clobbered errno value, exposing
an OpenJDK bug (JDK-8270244).

This patch fixes by open-code INLINE_VSYSCALL macro and replace all
INLINE_SYSCALL_CALL with INTERNAL_SYSCALL_CALLS.  Now for
__clock_gettime64x, the 64-bit vDSO is used and the 32-bit vDSO is
tried before falling back to 64-bit syscalls.

The previous code preferred 64-bit syscall for the case where the kernel
provides 64-bit time_t syscalls *and* also a 32-bit vDSO (in this case
the *64-bit* syscall should be preferable over the vDSO).  All
architectures that provides 32-bit vDSO (i386, mips, powerpc, s390)
modulo sparc; but I am not sure if some kernels versions do provide
only 32-bit vDSO while still providing 64-bit time_t syscall.
Regardless, for such cases the 64-bit time_t syscall is used if the
vDSO returns overflowed 32-bit time_t.

Tested on i686-linux-gnu (with a time64 and non-time64 kernel),
x86_64-linux-gnu.  Built with build-many-glibcs.py.

Co-authored-by: Florian Weimer <fweimer@redhat.com>
2021-07-12 17:37:56 -03:00
Florian Weimer
aaacde11f2 Reduce <limits.h> pollution due to dynamic PTHREAD_STACK_MIN
<limits.h> used to be a header file with no declarations.
GCC's libgomp includes it in a #pragma GCC visibility hidden block.
Including <unistd.h> from <limits.h> (indirectly) declares everything
in <unistd.h> with hidden visibility, resulting in linker failures.

This commit avoids C declarations in assembler mode and only declares
__sysconf in <limits.h> (and not the entire contents of <unistd.h>).
The __sysconf symbol is already part of the ABI.  PTHREAD_STACK_MIN
is no longer defined for __USE_DYNAMIC_STACK_SIZE && __ASSEMBLER__
because there is no possible definition.

Additionally, PTHREAD_STACK_MIN is now defined by <pthread.h> for
__USE_MISC because this is what developers expect based on the macro
name.  It also helps to avoid libgomp linker failures in GCC because
libgomp includes <pthread.h> before its visibility hacks.

Reviewed-by: Carlos O'Donell <carlos@redhat.com>
2021-07-12 18:43:32 +02:00
H.J. Lu
5d98a7dae9 Define PTHREAD_STACK_MIN to sysconf(_SC_THREAD_STACK_MIN)
The constant PTHREAD_STACK_MIN may be too small for some processors.
Rename _SC_SIGSTKSZ_SOURCE to _DYNAMIC_STACK_SIZE_SOURCE.  When
_DYNAMIC_STACK_SIZE_SOURCE or _GNU_SOURCE are defined, define
PTHREAD_STACK_MIN to sysconf(_SC_THREAD_STACK_MIN) which is changed
to MIN (PTHREAD_STACK_MIN, sysconf(_SC_MINSIGSTKSZ)).

Consolidate <bits/local_lim.h> with <bits/pthread_stack_min.h> to
provide a constant target specific PTHREAD_STACK_MIN value.

Reviewed-by: Carlos O'Donell <carlos@redhat.com>
2021-07-09 15:10:35 -07:00
Florian Weimer
7c241325d6 Force building with -fno-common
As a result, is not necessary to specify __attribute__ ((nocommon))
on individual definitions.

GCC 10 defaults to -fno-common on all architectures except ARC,
but this change is compatible with older GCC versions and ARC, too.

Reviewed-by: Carlos O'Donell <carlos@redhat.com>
2021-07-09 20:09:14 +02:00
Adhemerval Zanella
882d6e17bc posix: Add posix_spawn_file_actions_addclosefrom_np
This patch adds a way to close a range of file descriptors on
posix_spawn as a new file action.  The API is similar to the one
provided by Solaris 11 [1], where the file action causes the all open
file descriptors greater than or equal to input on to be closed when
the new process is spawned.

The function posix_spawn_file_actions_addclosefrom_np is safe to be
implemented by iterating over /proc/self/fd, since the Linux spawni.c
helper process does not use CLONE_FILES, so its has own file descriptor
table and any failure (in /proc operation) aborts the process creation
and returns an error to the caller.

I am aware that this file action might be redundant to the current
approach of POSIX in promoting O_CLOEXEC in more interfaces. However
O_CLOEXEC is still not the default and for some specific usages, the
caller needs to close all possible file descriptors to avoid them
leaking.  Some examples are CPython (discussed in BZ#10353) and OpenJDK
jspawnhelper [2] (where OpenJDK spawns a helper process to exactly
closes all file descriptors).  Most likely any environment which calls
functions that might open file descriptor under the hood and aim to use
posix_spawn might face the same requirement.

Checked on x86_64-linux-gnu and i686-linux-gnu on kernel 5.11 and 4.15.

[1] https://docs.oracle.com/cd/E36784_01/html/E36874/posix-spawn-file-actions-addclosefrom-np-3c.html
[2] https://github.com/openjdk/jdk/blob/master/src/java.base/unix/native/libjava/childproc.c#L82
2021-07-08 14:08:15 -03:00
Adhemerval Zanella
607449506f io: Add closefrom [BZ #10353]
The function closes all open file descriptors greater than or equal to
input argument.  Negative values are clamped to 0, i.e, it will close
all file descriptors.

As indicated by the bug report, this is a common symbol provided by
different systems (Solaris, OpenBSD, NetBSD, FreeBSD) and, although
its has inherent issues with not taking in consideration internal libc
file descriptors (such as syslog), this is also a common feature used
in multiple projects [1][2][3][4][5].

The Linux fallback implementation iterates over /proc and close all
file descriptors sequentially.  Although it was raised the questioning
whether getdents on /proc/self/fd might return disjointed entries
when file descriptor are closed; it does not seems the case on my
testing on multiple kernel (v4.18, v5.4, v5.9) and the same strategy
is used on different projects [1][2][3][5].

Also, the interface is set a fail-safe meaning that a failure in the
fallback results in a process abort.

Checked on x86_64-linux-gnu and i686-linux-gnu on kernel 5.11 and 4.15.

[1] 5238e95759/src/basic/fd-util.c (L217)
[2] ddf4b77e11/src/lxc/start.c (L236)
[3] 9e4f2f3a6b/Modules/_posixsubprocess.c (L220)
[4] 5f47c0613e/src/libstd/sys/unix/process2.rs (L303-L308)
[5] https://github.com/openjdk/jdk/blob/master/src/java.base/unix/native/libjava/childproc.c#L82
2021-07-08 14:08:14 -03:00
Adhemerval Zanella
286286283e linux: Add close_range
It was added on Linux 5.9 (278a5fbaed89) with CLOSE_RANGE_CLOEXEC
added on 5.11 (582f1fb6b721f).  Although FreeBSD has added the same
syscall, this only adds the symbol on Linux ports.  This syscall is
required to provided a fail-safe way to implement the closefrom
symbol (BZ #10353).

Checked on x86_64-linux-gnu and i686-linux-gnu on kernel 5.11 and 4.15.
2021-07-08 14:08:13 -03:00
Florian Weimer
7fcdb53253 libio: Replace internal _IO_getdelim symbol with __getdelim
__getdelim is exported, _IO_getdelim is not.  Add a hidden prototype
for __getdelim.

Reviewed-by: Adhemerval Zanella  <adhemerval.zanella@linaro.org>
2021-07-07 18:33:52 +02:00
Joseph Myers
b46cfcef3f Update kernel version to 5.13 in tst-mman-consts.py
This patch updates the kernel version in the test tst-mman-consts.py
to 5.13.  (There are no new MAP_* constants covered by this test in
5.13 that need any other header changes.)

Tested with build-many-glibcs.py.
2021-07-07 13:24:05 +00:00
Florian Weimer
8ec022a037 nptl: Remove GLIBC_2.34 versions of __pthread_mutex_lock, __pthread_mutex_unlock
Now that there are no internal users anymore, these new symbol
versions can be removed from the public ABI.  The compatibility
symbols remain.

Reviewed-by: Adhemerval Zanella  <adhemerval.zanella@linaro.org>
2021-07-07 08:41:17 +02:00
Adhemerval Zanella
cf2256196c linux: Fix setsockopt fallback
The final 2 arguments for SO_TIMESTAMP/SO_TIMESTAMPNS are being set
wrongly.

Checked on x86_64-linux-gnu and i686-linux-gnu.
2021-07-06 11:45:35 -03:00
Adhemerval Zanella
f7de21498d linux: Use the expected size for SO_TIMESTAMP{NS} convertion
Kernel returns 32-bit values for COMPAT_SO_TIMESTAMP{NS}_OLD,
not 64-bit values.

Checked on x86_64-linux-gnu and i686-linux-gnu.
2021-07-06 11:45:35 -03:00
Adhemerval Zanella
4b93a93e40 linux: Consolidate Linux setsockopt implementation
This patch consolidates the setsockopt implementation on
sysdeps/unix/sysv/linux/getsockopt.c.  The changes are:

  1. Remove it from auto-generation syscalls.list on all architectures.

  2. Add __ASSUME_SETSOCKOPT_SYSCALL as default and undef if for
     specific kernel versions on some architectures.

This also fix a potential issue where 32-bit time_t ABI should use the
linux setsockopt which overrides the underlying SO_* constants used for
socket timestamping for _TIME_BITS=64.

Checked on x86_64-linux-gnu and i686-linux-gnu.
2021-07-06 11:45:35 -03:00
Adhemerval Zanella
1c46663a70 linux: Consolidate Linux getsockopt implementation
This patch consolidates the getsockopt Linux syscall implementation on
sysdeps/unix/sysv/linux/getsockopt.c.  The changes are:

  1. Remove it from auto-generation syscalls.list on all architectures.

  2. Add __ASSUME_GETSOCKOPT_SYSCALL as default and undef if for
     specific kernel versions on some architectures.

This also fix a potential issue where 32-bit time_t ABI should use the
linux getsockopt which overrides the underlying SO_* constants used for
socket timestamping for _TIME_BITS=64.

Checked on x86_64-linux-gnu and i686-linux-gnu.
2021-07-06 11:45:35 -03:00
Khem Raj
c8935581de linux: Check for null value msghdr struct before use
This avoids crashes in libc when cmsg is null and refrencing msg
structure when it is null

Signed-off-by: Khem Raj <raj.khem@gmail.com>
Reviewed-by: Adhemerval Zanella  <adhemerval.zanella@linaro.org>
2021-07-05 15:11:13 -03:00
Florian Weimer
dbb949f53d resolv: Move libanl into libc (if libpthread is in libc)
The symbols gai_cancel, gai_error, gai_suspend, getaddrinfo_a,
__gai_suspend_time64 were moved using scripts/move-symbol-to-libc.py.

For Hurd (which remains !PTHREAD_IN_LIBC), a few #define redirects
had to be added because several pthread functions are not available
under __.  (Linux uses __ prefixes for most hidden aliases, and has
to in some cases to avoid linknamespace issues.)
2021-07-02 11:45:00 +02:00
Joseph Myers
b1b4f7209e Update syscall lists for Linux 5.13
Linux 5.13 has three new syscalls (landlock_create_ruleset,
landlock_add_rule, landlock_restrict_self).  Update syscall-names.list
and regenerate the arch-syscall.h headers with build-many-glibcs.py
update-syscalls.

Tested with build-many-glibcs.py.
2021-07-01 17:37:36 +00:00
Stefan Liebler
ba436665b1 Fix extra PLT reference in libc.so due to __glob64_time64 if build with gcc 7.5 on 32bit.
Starting with recent commit 84f7ce8447
"posix: Add glob64 with 64-bit time_t support", elf/check-localplt
fails due to extra PLT reference __glob64_time64 in __glob64_time64
itself.

This is observable with gcc 7.5 on x86_64 with -m32 or s390x with
-m31.  E.g. if build with gcc 10, gcc is generating a call to
__glob64_time64.localalias.

This patch is adding a hidden version of __glob64_time64 in the
same way as for __globfree64_time64.
2021-07-01 16:46:59 +02:00
Florian Weimer
eb68d7d23c Linux: Avoid calling malloc indirectly from __get_nprocs
malloc initialization depends on __get_nprocs, so using
scratch buffers in __get_nprocs may result in infinite recursion.

Reviewed-by: Carlos O'Donell <carlos@redhat.com>
Reviewed-by: Siddhesh Poyarekar <siddhesh@sourceware.org>
2021-06-30 17:41:47 +02:00
Florian Weimer
734c60ebb6 login: Move libutil into libc
The symbols forkpty, login, login_tty, logout, logwtmp, openpty
were moved using scripts/move-symbol-to-libc.py.

This is a single commit because most of the symbols are tied together
via forkpty, for example.

Several changes to use hidden prototypes are needed.  This commit
also updates pseudoterminal terminology on modified lines.

For 390 (31-bit), this commit follows the existing style for the
compat symbol version creation.

Reviewed-by: Adhemerval Zanella  <adhemerval.zanella@linaro.org>
2021-06-30 08:43:37 +02:00
Florian Weimer
8d1f854d60 login: Hidden prototypes for _getpt, __ptsname_r, grantpt, unlockpt
Reviewed-by: Adhemerval Zanella  <adhemerval.zanella@linaro.org>
2021-06-30 07:28:12 +02:00
Adhemerval Zanella
c32c868ab8 posix: Add _Fork [BZ #4737]
Austin Group issue 62 [1] dropped the async-signal-safe requirement
for fork and provided a async-signal-safe _Fork replacement that
does not run the atfork handlers.  It will be included in the next
POSIX standard.

It allow to close a long standing issue to make fork AS-safe (BZ#4737).
As indicated on the bug, besides the internal lock for the atfork
handlers itself; there is no guarantee that the handlers itself will
not introduce more AS-safe issues.

The idea is synchronize fork with the required internal locks to allow
children in multithread processes to use mostly of standard function
(even though POSIX states only AS-safe function should be used).  On
signal handles, _Fork should be used intead and only AS-safe functions
should be used.

For testing, the new tst-_Fork only check basic usage.  I also added
a new tst-mallocfork3 which uses the same strategy to check for
deadlock of tst-mallocfork2 but using threads instead of subprocesses
(and it does deadlock if it replaces _Fork with fork).

[1] https://austingroupbugs.net/view.php?id=62
2021-06-28 15:55:56 -03:00
Szabolcs Nagy
3101b96787 arm: align stack in clone [BZ 28020]
The arm PCS requires 8 byte aligned stack at function entry.
Previously unaligned stack could crash the clone child.

Fixes bug 28020.
2021-06-28 11:35:44 +01:00
Florian Weimer
30639e79d3 Linux: Cleanups after librt move
librt.so is no longer installed for PTHREAD_IN_LIBC, and tests
are not linked against it.  $(librt) is introduced globally for
shared tests that need to be linked for both PTHREAD_IN_LIBC
and !PTHREAD_IN_LIBC.

GLIBC_PRIVATE symbols that were needed during the transition are
removed again.

Reviewed-by: Carlos O'Donell <carlos@redhat.com>
2021-06-28 09:51:01 +02:00
Florian Weimer
477910b83e Linux: Move timer_settime, __timer_settime64 from librt to libc
The symbols were moved using scripts/move-symbol-to-libc.py.

The way the ABI intransition is implemented is changed with this
commit: the implementation is now consolidated in one file with a
TIMER_T_WAS_INT_COMPAT check.

The shared librt is now empty, so this commit adds a placeholder
symbol at the base version, GLIBC_2.2, and potentially at the
GLIBC_2.3.3 version as well (the leftover from the int/timer_t ABI
transition).

Reviewed-by: Adhemerval Zanella  <adhemerval.zanella@linaro.org>
2021-06-28 09:51:01 +02:00
Florian Weimer
a1d6ed027b Linux: Move timer_gettime, __timer_gettime64 from librt to libc
The symbols were moved using scripts/move-symbol-to-libc.py.

The way the ABI intransition is implemented is changed with this
commit: the implementation is now consolidated in one file with a
TIMER_T_WAS_INT_COMPAT check.

Reviewed-by: Adhemerval Zanella  <adhemerval.zanella@linaro.org>
2021-06-28 09:51:01 +02:00
Florian Weimer
df6d227e69 Linux: Move timer_getoverrun from librt to libc
The symbol was moved using scripts/move-symbol-to-libc.py.

The way the ABI intransition is implemented is changed with this
commit: the implementation is now consolidated in one file with a
TIMER_T_WAS_INT_COMPAT check.

Reviewed-by: Adhemerva Zanella  <adhemerval.zanella@linaro.org>
2021-06-28 09:51:00 +02:00
Florian Weimer
273a2a2ae8 Linux: Move timer_create, timer_delete from librt to libc
The symbols were moved using scripts/move-symbol-to-libc.py.

timer_create and timer_delete are tied together via the int/timer_t
compatibility code.  The way the ABI intransition is implemented
is changed with this commit: the implementation is now consolidated
in one file with a TIMER_T_WAS_INT_COMPAT check.

Reviewed-by: Adhemerval Zanella  <adhemerval.zanella@linaro.org>
2021-06-28 09:51:00 +02:00
Florian Weimer
d7d0efec47 Linux: Define TIMER_T_WAS_INT_COMPAT in kernel-posix-timers.h
This is almost equivalent to __WORDSIZE == 64
&& OTHER_SHLIB_COMPAT (librt, GLIBC_2_1, GLIBC_2_3_3), except
that this expression is true for mips64/n64 targets as well,
even though those did not undergo the timer_t transition.

Reviewed-by: Carlos O'Donell <carlos@redhat.com>
2021-06-28 09:51:00 +02:00
Florian Weimer
2c16cb88a6 Linux: Move timer helper routines from librt to libc
This adds several temporary GLIBC_PRIVATE exports.  The symbol names
are changed so that they all start with __timer_.

It is now possible to invoke the fork handler directly, so
pthread_atfork is no longer necessary.  The associated error cannot
happen anymore, and cancellation handling can be removed from
the helper thread routine.

Reviewed-by: Adhemerval Zanella  <adhemerval.zanella@linaro.org>
2021-06-25 12:21:12 +02:00
Florian Weimer
1a5a653be2 Linux: Move mq_unlink from librt to libc
The symbol was moved using scripts/move-symbol-to-libc.py.
A placeholder symbol is needed on some architectures for the
GLIBC_2.3.4 version.

Reviewed-by: Adhemerva Zanella  <adhemerval.zanella@linaro.org>
2021-06-25 12:21:12 +02:00