Commit Graph

11 Commits

Author SHA1 Message Date
Adhemerval Zanella
01bd62517c Remove tls.h inclusion from internal errno.h
The tls.h inclusion is not really required and limits possible
definition on more arch specific headers.

This is a cleanup to allow inline functions on sysdep.h, more
specifically on i386 and ia64 which requires to access some tls
definitions its own.

No semantic changes expected, checked with a build against all
affected ABIs.
2020-11-13 12:59:19 -03:00
Adhemerval Zanella
f26d456b98 linux: Fix __NSIG_WORDS and add __NSIG_BYTES
The __NSIG_WORDS value is based on minimum number of words to hold
the maximum number of signals supported by the architecture.

This patch also adds __NSIG_BYTES, which is the number of bytes
required to represent the supported number of signals.  It is used in
syscalls which takes a sigset_t.

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

Tested-by: Carlos O'Donell <carlos@redhat.com>
Reviewed-by: Carlos O'Donell <carlos@redhat.com>
2020-07-07 14:10:58 -03:00
Adhemerval Zanella
27d83441a2 Block all signals on timer_create thread (BZ#10815)
The behavior of the signal mask on threads created by timer_create
for SIGEV_THREAD timers are implementation-defined and glibc explicit
unblocks all signals before calling the user-defined function.

This behavior, although not incorrect standard-wise, opens a race if a
program using a blocked rt-signal plus sigwaitinfo (and without an
installed signal handler for the rt-signal) receives a signal while
executing the used-defined function for SIGEV_THREAD.

A better alternative discussed in bug report is to rather block all
signals (besides the internal ones not available to application
usage).

This patch fixes this issue by only unblocking SIGSETXID (used on
set*uid function) and SIGCANCEL (used for thread cancellation).

Checked on x86_64-linux-gnu and i686-linux-gnu.
2020-02-19 13:46:31 -03:00
Adhemerval Zanella
bc2eb9321e linux: Remove INTERNAL_SYSCALL_DECL
With all Linux ABIs using the expected Linux kABI to indicate
syscalls errors, the INTERNAL_SYSCALL_DECL is an empty declaration
on all ports.

This patch removes the 'err' argument on INTERNAL_SYSCALL* macro
and remove the INTERNAL_SYSCALL_DECL usage.

Checked with a build against all affected ABIs.
2020-02-14 21:12:45 -03:00
Joseph Myers
d614a75396 Update copyright dates with scripts/update-copyrights. 2020-01-01 00:14:33 +00:00
Adhemerval Zanella
58bd592536 Fix return code for __libc_signal_* functions
The functions do not fail regardless of the argument value.  Also, for
Linux the return value is not correct on some platforms due the missing
usage of INTERNAL_SYSCALL_ERROR_P / INTERNAL_SYSCALL_ERRNO macros.

Checked on x86_64-linux-gnu, i686-linux-gnu, and sparc64-linux-gnu.
2019-12-27 11:18:23 -03:00
Adhemerval Zanella
1b132d55e2 Fix __libc_signal_block_all on sparc64
The posix_spawn on sparc issues invalid sigprocmask calls:

  rt_sigprocmask(0xffe5e15c /* SIG_??? */, ~[], 0xffe5e1dc, 8) = -1 EINVAL (Invalid argument)

Which make support/tst-support_capture_subprocess fails with random
output (due the child signal being wrongly captured by the parent).

Tracking the culprit it seems to be a wrong code generation in the
INTERNAL_SYSCALL due the automatic sigset_t used on
__libc_signal_block_all:

  return INTERNAL_SYSCALL (rt_sigprocmask, err, 4, SIG_BLOCK, &SIGALL_SET,
                          set, _NSIG / 8);

Where SIGALL_SET is defined as:

  ((__sigset_t) { .__val = {[0 ...  _SIGSET_NWORDS-1 ] =  -1 } })

Building the expanded __libc_signal_block_all on sparc64 with recent
compiler (gcc 8.3.1 and 9.1.1):

  #include <signal>

  int
  _libc_signal_block_all (sigset_t *set)
  {
    INTERNAL_SYSCALL_DECL (err);
    return INTERNAL_SYSCALL (rt_sigprocmask, err, 4, SIG_BLOCK, &SIGALL_SET,
			     set, _NSIG / 8);
  }

The first argument (SIG_BLOCK) is not correctly set on 'o0' register:

  __libc_signal_block_all:
	save    %sp, -304, %sp
	add     %fp, 1919, %o0
	mov     128, %o2
	sethi   %hi(.LC0), %o1
	call    memcpy, 0
	 or     %o1, %lo(.LC0), %o1
	add     %fp, 1919, %o1
	mov     %i0, %o2
	mov     8, %o3
	mov     103, %g1
	ta      0x6d;
	bcc,pt  %xcc, 1f
	mov     0, %g1
	sub     %g0, %o0, %o0
	mov     1, %g1
     1:	sra     %o0, 0, %i0
	return  %i7+8
	 nop

Where if SIGALL_SET is defined a const object, gcc correctly sets the
expected kernel argument in correct register:

        sethi   %hi(.LC0), %o1
        call    memcpy, 0
         or     %o1, %lo(.LC0), %o1
   ->   mov     1, %o0
	add     %fp, 1919, %o1

Another possible fix is use a static const object.  Although there
should not be a difference between a const compound literal and a static
const object, the gcc C99 status page [1] has a note stating that this
optimization is not implemented:

  "const-qualified compound literals could share storage with each
   other and with string literals, but currently don't.".

This patch fixes it by moving both sigset_t that represent the
signal sets to static const data object.  It generates slight better
code where the object reference is used directly instead of a stack
allocation plus the content materialization.

Checked on x86_64-linux-gnu, i686-linux-gnu, and sparc64-linux-gnu.

[1] https://gcc.gnu.org/c99status.html
2019-12-19 10:30:49 -03:00
Paul Eggert
5a82c74822 Prefer https to http for gnu.org and fsf.org URLs
Also, change sources.redhat.com to sourceware.org.
This patch was automatically generated by running the following shell
script, which uses GNU sed, and which avoids modifying files imported
from upstream:

sed -ri '
  s,(http|ftp)(://(.*\.)?(gnu|fsf|sourceware)\.org($|[^.]|\.[^a-z])),https\2,g
  s,(http|ftp)(://(.*\.)?)sources\.redhat\.com($|[^.]|\.[^a-z]),https\2sourceware.org\4,g
' \
  $(find $(git ls-files) -prune -type f \
      ! -name '*.po' \
      ! -name 'ChangeLog*' \
      ! -path COPYING ! -path COPYING.LIB \
      ! -path manual/fdl-1.3.texi ! -path manual/lgpl-2.1.texi \
      ! -path manual/texinfo.tex ! -path scripts/config.guess \
      ! -path scripts/config.sub ! -path scripts/install-sh \
      ! -path scripts/mkinstalldirs ! -path scripts/move-if-change \
      ! -path INSTALL ! -path  locale/programs/charmap-kw.h \
      ! -path po/libc.pot ! -path sysdeps/gnu/errlist.c \
      ! '(' -name configure \
            -execdir test -f configure.ac -o -f configure.in ';' ')' \
      ! '(' -name preconfigure \
            -execdir test -f preconfigure.ac ';' ')' \
      -print)

and then by running 'make dist-prepare' to regenerate files built
from the altered files, and then executing the following to cleanup:

  chmod a+x sysdeps/unix/sysv/linux/riscv/configure
  # Omit irrelevant whitespace and comment-only changes,
  # perhaps from a slightly-different Autoconf version.
  git checkout -f \
    sysdeps/csky/configure \
    sysdeps/hppa/configure \
    sysdeps/riscv/configure \
    sysdeps/unix/sysv/linux/csky/configure
  # Omit changes that caused a pre-commit check to fail like this:
  # remote: *** error: sysdeps/powerpc/powerpc64/ppc-mcount.S: trailing lines
  git checkout -f \
    sysdeps/powerpc/powerpc64/ppc-mcount.S \
    sysdeps/unix/sysv/linux/s390/s390-64/syscall.S
  # Omit change that caused a pre-commit check to fail like this:
  # remote: *** error: sysdeps/sparc/sparc64/multiarch/memcpy-ultra3.S: last line does not end in newline
  git checkout -f sysdeps/sparc/sparc64/multiarch/memcpy-ultra3.S
2019-09-07 02:43:31 -07:00
Joseph Myers
04277e02d7 Update copyright dates with scripts/update-copyrights.
* All files with FSF copyright notices: Update copyright dates
	using scripts/update-copyrights.
	* locale/programs/charmap-kw.h: Regenerated.
	* locale/programs/locfile-kw.h: Likewise.
2019-01-01 00:11:28 +00:00
Adhemerval Zanella
d2dc5467c6 Filter out NPTL internal signals (BZ #22391)
This patch filters out the internal NPTL signals (SIGCANCEL/SIGTIMER and
SIGSETXID) from signal functions.  GLIBC on Linux requires both signals to
proper implement pthread cancellation, posix timers, and set*id posix
thread synchronization.

And not filtering out the internal signal is troublesome:

  - A conformant program on a architecture that does not filter out the
    signals might inadvertently disable pthread asynchronous cancellation,
    set*id synchronization or posix timers.

  - It might also to security issues if SIGSETXID is masked and set*id
    functions are called (some threads might have effective user or group
    id different from the rest).

The changes are basically:

  - Change __is_internal_signal to bool and used on all signal function
    that has a signal number as input.  Also for signal function which accepts
    signals sets (sigset_t) it assumes that canonical function were used to
    add/remove signals which lead to some input simplification.

  - Fix tst-sigset.c to avoid check for SIGCANCEL/SIGTIMER and SIGSETXID.
    It is rewritten to check each signal indidually and to check realtime
    signals using canonical macros.

  - Add generic __clear_internal_signals and __is_internal_signal
    version since both symbols are used on generic implementations.

  - Remove superflous sysdeps/nptl/sigfillset.c.

  - Remove superflous SIGTIMER handling on Linux __is_internal_signal
    since it is the same of SIGCANCEL.

  - Remove dangling define and obvious comment on nptl/sigaction.c.

Checked on x86_64-linux-gnu.

	[BZ #22391]
	* nptl/sigaction.c (__sigaction): Use __is_internal_signal to
	check for internal nptl signals.
	* nptl/sigaction.c (__sigaction): Likewise.
	* signal/sigaddset.c (sigaddset): Likewise.
	* signal/sigdelset.c (sigdelset): Likewise.
	* sysdeps/posix/signal.c (__bsd_signal): Likewise.
	* sysdeps/posix/sigset.c (sigset): Call and check sigaddset return
	value.
	* signal/sigfillset.c (sigfillset): User __clear_internal_signals
	to filter out internal nptl signals.
	* signal/tst-sigset.c (do_test): Check ech signal indidually and
	also check realtime signals using standard macros.
	* sysdeps/generic/internal-signals.h (__clear_internal_signals,
	__is_internal_signal, __libc_signal_block_all,
	__libc_signal_block_app, __libc_signal_restore_set): New functions.
	* sysdeps/nptl/sigfillset.c: Remove file.
	* sysdeps/unix/sysv/linux/internal-signals.h (__is_internal_signal):
	Change return to bool.
	(__clear_internal_signals): Remove SIGTIMER clean since it is
	equal to SIGCANEL on Linux.
	* sysdeps/unix/sysv/linux/sigtimedwait.c (__sigtimedwait): Assume
	signal set was constructed using standard functions.

Reported-by: Yury Norov <ynorov@caviumnetworks.com>
2018-04-03 13:30:49 -03:00
Adhemerval Zanella
92aabad9b2 Rename nptl-signals.h to internal-signals.h
This patch renames the nptl-signals.h header to internal-signals.h.
On Linux the definitions and functions are not only NPTL related, but
used for other POSIX definitions as well (for instance SIGTIMER for
posix times, SIGSETXID for id functions, and signal block/restore
helpers) and since generic functions will be places and used in generic
implementation it makes more sense to decouple it from NPTL.

Checked on x86_64-linux-gnu.

	* sysdeps/nptl/nptl-signals.h: Move to ...
	* sysdeps/generic/internal-signals.h: ... here.  Adjust internal
	comments.
	* sysdeps/unix/sysv/linux/internal-signals.h: Add include guards.
	(__nptl_is_internal_signal): Rename to __is_internal_signal.
	(__nptl_clear_internal_signals): Rename to __clear_internal_signals.
	* sysdeps/unix/sysv/linux/raise.c: Adjust nptl-signal.h to
	include-signals.h rename.
	* nptl/pthreadP.h: Likewise.
	* sysdeps/unix/sysv/linux/spawni.c (__spawni_child): Call
	__is_internal_signal instead of __nptl_is_internal_signal.
2018-02-22 16:43:59 -03:00