Commit 43c29487 tried to fix the vfork aliases in libpthread.so on MIPS
and SPARC, but failed to do it correctly, introducing an ABI change.
This patch does the remaining changes needed to align the MIPS and SPARC
vfork implementations with the other architectures. That way the the
alpha version of pt-vfork.S works correctly for MIPS and SPARC. The
changes for alpha were done in 82aab97c.
Changelog:
* sysdeps/unix/sysv/linux/mips/vfork.S (__vfork): Rename into
__libc_vfork.
(__vfork) [IS_IN (libc)]: Remove alias.
(__libc_vfork) [IS_IN (libc)]: Define as an alias.
* sysdeps/unix/sysv/linux/sparc/sparc32/vfork.S: Likewise.
* sysdeps/unix/sysv/linux/sparc/sparc64/vfork.S: Likewise.
This patch fixes the p{readv,writev}{64} consolidation implementation
from commits 4e77815 and af5fdf5. Different from pread/pwrite
implementation, preadv/pwritev implementation does not require
__ALIGNMENT_ARG because kernel syscall prototypes define
the high and low part of the off_t, if it is the case, directly
(different from pread/pwrite where the architecture ABI for passing
64-bit values must be in consideration for passsing the arguments).
It also adds some basic tests for preadv/pwritev.
Tested on x86_64, i686, and armhf.
* misc/Makefile (tests): Add tst-preadvwritev and tst-preadvwritev64.
* misc/tst-preadvwritev.c: New file.
* misc/tst-preadvwritev64.c: Likewise.
* sysdeps/unix/sysv/linux/preadv.c (preadv): Remove SYSCALL_LL{64}
usage.
* sysdeps/unix/sysv/linux/preadv64.c (preadv64): Likewise.
* sysdeps/unix/sysv/linux/pwritev.c (pwritev): Likewise.
* sysdeps/unix/sysv/linux/pwritev64.c (pwritev64): Likewise.
* sysdeps/unix/sysv/linux/sysdep.h (LO_HI_LONG): New macro.
With recent binutils versions the GNU libc fails to build on at least
MISP and SPARC, with this kind of error:
/home/aurel32/glibc/glibc-build/nptl/libpthread.so:(*IND*+0x0): multiple definition of `vfork@GLIBC_2.0'
/home/aurel32/glibc/glibc-build/nptl/libpthread.so::(.text+0xee50): first defined here
It appears that on these architectures pt-vfork.S includes vfork.S
(through the alpha version of pt-vfork.S) and that the __vfork aliases
are not conditionalized on IS_IN (libc) like on other architectures.
Therefore the aliases are also wrongly included in libpthread.so.
Fix this by properly conditionalizing the aliases like on other
architectures.
Changelog:
* sysdeps/unix/sysv/linux/mips/vfork.S (__vfork): Conditionalize
hidden_def, weak_alias and strong_alias on [IS_IN (libc)].
* sysdeps/unix/sysv/linux/sparc/sparc32/vfork.S: Likewise.
* sysdeps/unix/sysv/linux/sparc/sparc64/vfork.S: Likewise.
TS 18661 adds nextup and nextdown functions alongside nextafter to provide
support for float128 equivalent to it. This patch adds nextupl, nextup,
nextupf, nextdownl, nextdown and nextdownf to libm before float128 support.
The nextup functions return the next representable value in the direction of
positive infinity and the nextdown functions return the next representable
value in the direction of negative infinity. These are currently enabled
as GNU extensions.
This patch removes __ASSUME_FUTEX_LOCK_PI usage and assumes that
kernel will correctly return if it supports or not
futex_atomic_cmpxchg_inatomic.
Current PI mutex code already has runtime support by calling
prio_inherit_missing and returns ENOTSUP if the futex operation fails
at initialization (it issues a FUTEX_UNLOCK_PI futex operation).
Also, current minimum supported kernel (v3.2) will return ENOSYS if
futex_atomic_cmpxchg_inatomic is not supported in the system:
kernel/futex.c:
2628 long do_futex(u32 __user *uaddr, int op, u32 val, ktime_t *timeout,
2629 u32 __user *uaddr2, u32 val2, u32 val3)
2630 {
2631 int ret = -ENOSYS, cmd = op & FUTEX_CMD_MASK;
[...]
2667 case FUTEX_UNLOCK_PI:
2668 if (futex_cmpxchg_enabled)
2669 ret = futex_unlock_pi(uaddr, flags);
[...]
2686 return ret;
2687 }
The futex_cmpxchg_enabled is initialized by calling cmpxchg_futex_value_locked,
which calls futex_atomic_cmpxchg_inatomic.
For ARM futex_atomic_cmpxchg_inatomic will be either defined (if both
CONFIG_CPU_USE_DOMAINS and CONFIG_SMP are not defined) or use the
default generic implementation that returns ENOSYS.
For m68k is uses the default generic implementation.
For mips futex_atomic_cmpxchg_inatomic will return ENOSYS if cpu has no
'cpu_has_llsc' support (defined by each chip supporte inside kernel).
For sparc, 32-bit kernel will just use default generic implementation,
while 64-bit kernel has support.
Tested on ARM (v3.8 kernel) and x86_64.
* nptl/pthread_mutex_init.c [__ASSUME_FUTEX_LOCK_PI]
(prio_inherit_missing): Remove define.
* sysdeps/unix/sysv/linux/arm/kernel-features.h
(__ASSUME_FUTEX_LOCK_PI): Likewise.
* sysdeps/unix/sysv/linux/kernel-features.h (__ASSUME_FUTEX_LOCK_PI):
Likewise.
* sysdeps/unix/sysv/linux/m68k/kernel-features.h
(__ASSUME_FUTEX_LOCK_PI): Likewise.
* sysdeps/unix/sysv/linux/mips/kernel-features.h
(__ASSUME_FUTEX_LOCK_PI): Likewise.
* sysdeps/unix/sysv/linux/sparc/kernel-features.h
(__ASSUME_FUTEX_LOCK_PI): Likewise.
After some discussion in libc-alpha about this POSIX compliance fix, I see
that GLIBC should indeed revert back to previous definition of msghdr and
cmsghdr and implementation of sendmsg, recvmsg, sendmmsg, recvmmsg due some
reasons:
* The possible issue where the syscalls wrapper add the compatibility
layer is quite limited in scope and range. And kernel current
also add some limits to the values on the internal msghdr and
cmsghdr fields:
- msghdr::msg_iovlen larger than UIO_MAXIOV (1024) returns
EMSGSIZE.
- msghdr::msg_controllen larger than INT_MAX returns ENOBUFS.
* There is a small performance hit for recvmsg/sendmsg/recmmsg which
is neglectable, but it is a big hit for sendmmsg since now instead
of calling the syscall for the packed structure, GLIBC is calling
multiple sendmsg. This defeat the very existence of the syscall.
* It currently breaks libsanitizer build on GCC [1] (I fixed on compiler-rt).
However the fix is incomplete because it does add any runtime check
since libsanitizer currently does not have any facility to intercept
symbols with multiple version [2].
This, along with incorret dlsym/dlvsym return for versioned symbol due
another bug [3], makes hard to interpose versioned symbols.
Also, current approach of fixing GCC PR#71445 leads to half-baked
solutions without versioned symbol interposing.
This patch basically reverts commits 2f0dc39029, 222c2d7f43,
af7f7c7ec8. I decided to not revert abf29edd4a (Adjust
kernel-features.h defaults for recvmsg and sendmsg) mainly because it
does not really address the POSIX compliance original issue and also
adds some cleanups.
Tested on x86, i386, s390, s390x, aarch64, and powerpc64le.
[1] https://gcc.gnu.org/bugzilla/show_bug.cgi?id=71445
[2] https://github.com/google/sanitizers/issues/628
[3] https://sourceware.org/bugzilla/show_bug.cgi?id=14932
* conform/data/sys/socket.h-data (msghdr.msg_iovlen): Add xfail-.
(msghdr.msg_controllen): Likewise.
(cmsghdr.cmsg_len): Likewise.
* nptl/Makefile (libpthread-routines): Remove ptw-oldrecvmsg and
ptw-oldsendmsg.
(CFLAGS-oldrecvmsg.c): Remove rule.
(CFLAGS-oldsendmsg.c): Likewise.
(CFLAGS-recvmsg.c): Add rule.
(CFLAGS-sendmsg.c): Likewise.
* sysdeps/unix/sysv/linux/Makefile (sysdep_routines): Remove
oldrecvmsg, oldsendmsg, oldrecvmmsg, oldsendmmsg.
(CFLAGS-recvmsg.c): Remove rule.
(CFLAGS-sendmsg.c): Likewise.
(CFLAGS-oldrecvmsg.c): Likewise.
(CFLAGS-oldsendmsg.c): Likewise.
(CFLAGS-recvmmsg.c): Likewise.
* sysdeps/unix/sysv/linux/bits/socket.h (msghdr.msg_iovlen): Revert
to kernel defined interfaces.
(msghdr.msg_controllen): Likewise.
(cmsghdr.cmsg_len): Likewise.
(msghdr.__glibc_reserved1): Remove member.
(msghdr.__glibc_reserved2): Likewise.
(cmsghdr.__glibc_reserved1): Likewise.
* sysdeps/unix/sysv/linux/oldrecvmmsg.c: Remove file.
* sysdeps/unix/sysv/linux/oldrecvmsg.c: Likewise.
* sysdeps/unix/sysv/linux/oldsendmmsg.c: Likewise.
* sysdeps/unix/sysv/linux/oldsendmsg.c: Likewise.
* sysdeps/unix/sysv/linux/recvmmsg.c: Revert back to previous
version.
* sysdeps/unix/sysv/linux/recvmsg.c: Likewise.
* sysdeps/unix/sysv/linux/sendmmsg.c: Likewise.
* sysdeps/unix/sysv/linux/sendmsg.c: Likewise.
* sysdeps/unix/sysv/linux/aarch64/Versions [libc] (GLIBC_2.24):
Remove recvmsg and sendmsg.
* sysdeps/unix/sysv/linux/alpha/Versions [libc] (GLIBC_2.24):
Likewise.
* sysdeps/unix/sysv/linux/hppa/Versions [libc] (GLIBC_2.24):
Likewise.
* sysdeps/unix/sysv/linux/i386/Versions [libc] (GLIBC_2.24): Likewise.
* sysdeps/unix/sysv/linux/m68k/Versions [libc] (GLIBC_2.24): Likewise.
* sysdeps/unix/sysv/linux/microblaze/Versions [libc] (GLIBC_2.24):
Likewise.
* sysdeps/unix/sysv/linux/mips/mips32/Versions [libc] (GLIBC_2.24):
Likewise.
* sysdeps/unix/sysv/linux/mips/mips64/n32/Versions
[libc] (GLIBC_2.24): Likewise.
* sysdeps/unix/sysv/linux/nios2/Versions [libc] (GLIBC_2.24):
Likewise.
* sysdeps/unix/sysv/linux/powerpc/Versions [libc] (GLIBC_2.24):
Likewise.
* sysdeps/unix/sysv/linux/powerpc/powerpc64/Versions
[libc] (GLIBC_2.24): Likewise.
* sysdeps/unix/sysv/linux/s390/s390-32/Versions [libc] (GLIBC_2.24):
Likewise.
* sysdeps/unix/sysv/linux/s390/s390-64/Versions [libc] (GLIBC_2.24):
Likewise.
* sysdeps/unix/sysv/linux/sh/Versions [libc] (GLIBC_2.24): Likewise.
* sysdeps/unix/sysv/linux/sparc/Versions [libc] (GLIBC_2.24):
Likewise.
* sysdeps/unix/sysv/linux/sparc/sparc64/Versions [libc] (GLIBC_2.24):
Likewise.
* sysdeps/unix/sysv/linux/tile/Versions [libc] (GLIBC_2.24):
Likewise.
* sysdeps/unix/sysv/linux/x86_64/Versions [libc] (GLIBC_2.24):
Likewise.
* sysdeps/unix/sysv/linux/tile/tilegx/tilegx64/Versions: Remove file
* sysdeps/unix/sysv/linux/x86_64/64/Versions: Likewise.
* sysdeps/unix/sysv/linux/mips/mips64/n64/Versions: Likewise.
* sysdeps/unix/sysv/linux/aarch64/libc.abilist: Remove new 2.24
version for {recv,send,recm,sendm}msg.
* sysdeps/unix/sysv/linux/alpha/libc.abilist: Likewise.
* sysdeps/unix/sysv/linux/arm/libc.abilist: Likewise.
* sysdeps/unix/sysv/linux/hppa/libc.abilist: Likewise.
* sysdeps/unix/sysv/linux/i386/libc.abilist: Likewise.
* sysdeps/unix/sysv/linux/ia64/libc.abilist: Likewise.
* sysdeps/unix/sysv/linux/m68k/coldfire/libc.abilist: Likewise.
* sysdeps/unix/sysv/linux/m68k/m680x0/libc.abilist: Likewise.
* sysdeps/unix/sysv/linux/microblaze/libc.abilist: Likewise.
* sysdeps/unix/sysv/linux/mips/mips32/fpu/libc.abilist: Likewise.
* sysdeps/unix/sysv/linux/mips/mips32/nofpu/libc.abilist: Likewise.
* sysdeps/unix/sysv/linux/mips/mips64/n32/libc.abilist: Likewise.
* sysdeps/unix/sysv/linux/mips/mips64/n64/libc.abilist: Likewise.
* sysdeps/unix/sysv/linux/powerpc/powerpc32/fpu/libc.abilist:
Likewise.
* sysdeps/unix/sysv/linux/powerpc/powerpc32/nofpu/libc.abilist:
Likewise.
* sysdeps/unix/sysv/linux/powerpc/powerpc64/libc-le.abilist: Likewise.
* sysdeps/unix/sysv/linux/powerpc/powerpc64/libc.abilist: Likewise.
* sysdeps/unix/sysv/linux/s390/s390-32/libc.abilist: Likewise.
* sysdeps/unix/sysv/linux/s390/s390-64/libc.abilist: Likewise.
* sysdeps/unix/sysv/linux/nios2/libc.abilist: Likewise.
* sysdeps/unix/sysv/linux/sh/libc.abilist: Likewise.
* sysdeps/unix/sysv/linux/sparc/sparc32/libc.abilist: Likewise.
* sysdeps/unix/sysv/linux/sparc/sparc64/libc.abilist: Likewise.
* sysdeps/unix/sysv/linux/tile/tilegx/tilegx32/libc.abilist: Likewise.
* sysdeps/unix/sysv/linux/tile/tilegx/tilegx64/libc.abilist: Likewise.
* sysdeps/unix/sysv/linux/tile/tilepro/libc.abilist: Likewise.
* sysdeps/unix/sysv/linux/x86_64/64/libc.abilist: Likewise.
* sysdeps/unix/sysv/linux/x86_64/x32/libc.abilist: Likewise.
In: https://sourceware.org/glibc/wiki/Synchronizing_Headers
we explain how we synchronize our headers with Linux kernel
headers.
In order to synchronize with the Linux linux/in6.h and
linux/ipv6.h headers we checked for their guard macros and
then defined __USE_KERNEL_IPV6_DEFS and conditionalized code
on this macro.
In upstream kernel 56c176c9 the _UAPI prefix was stripped and
this broke our synchronized headers again. We now need to check
for _LINUX_IN6_H and _IPV6_H, and keep checking the old versions
of the header guard checks for maximum backwards compatibility
with older Linux headers (the history is actually a bit muddled
here and it appears upstream linus kernel broke this 10 months
*before* our fix was ever applied to glibc, but without glibc
testing we didn't notice and distro kernels have their own
testing to fix this).
This patch fixes synchronization with linux/in6.h and
with netinet/in.h.
In C++11 18.5.12 says "Objects shall not be destroyed as a
result of calling quick_exit." In C11 quick_exit is silent
about thread object destruction. Therefore to make glibc
C++ compliant we do not call any thread local destructors.
A new regression test verifies the fix.
I will note that C++11 18.5.3 makes it clear that C++
defines additional requirements for _Exit() to prevent it
from executing destructors.
Given that the point of _Exit() is to terminate the process
immediately it makes sense the C and C++ should line up
and avoid calling destructors.
No failures. New regtest passes.
This patch consolidates all the pwritev{64} implementation for Linux
in only one (sysdeps/unix/sysv/linux/pwritev{64}.c). It also removes the
syscall from the auto-generation using assembly macros.
It was based on previous pwrite/pwrite64 consolidation patch. The new macro
SYSCALL_LL{64} is used to handle the offset argument and alias is created
for __ASSUME_OFF_DIFF_OFF64 in case of pread64.
Checked on x86_64, i386, aarch64, and powerpc64le.
* misc/Makefile (CFLAGS-pwritev.c): New variable: add cancellation
required flags.
(CFLAGS-pwritev64.c): Likewise.
* sysdeps/unix/sysv/linux/generic/wordsize-32/pwritev.c: Remove file.
* sysdeps/unix/sysv/linux/generic/wordsize-32/pwritev64.c: Likewise.
* sysdeps/unix/sysv/linux/mips/mips64/n64/pwritev64.c: Likewise.
* sysdeps/unix/sysv/linux/wordsize-64/pwritev.c: Likewise.
* sysdeps/unix/sysv/linux/wordsize-64/pwritev64.: Likwise.
* sysdeps/unix/sysv/linux/x86_64/x32/syscalls.list (pwritev): Remove
syscall from auto-generation.
* sysdeps/unix/sysv/linux/pwritev.c: Rewrite implementation.
[WORDSIZE == 64] (pwritev64): Remove macro.
[!PWRITEV] (PWRITEV): Likewise.
[!PWRITEV] (PWRITEV_REPLACEMENT): Likewise.
[!PWRITEV] (PWRITE): Likewise.
[!PWRITEV] (OFF_T): Likewise.
[!__ASSUME_PWRITEV] (PWRITEV_REPLACEMENT): Likewise.
(LO_HI_LONG): Remove macro.
[__WORDSIZE != 64 || __ASSUME_OFF_DIFF_OFF64] (pwritev): Add function.
* sysdeps/unix/sysv/linux/pwritev64.c: Rewrite implementation.
(PWRITEV): Remove macro.
(PWRITEV_REPLACEMENTE): Likewise.
(PWRITE): Likewise.
(OFF_T): Likewise.
(pwritev64): New function.
* nptl/tst-cancel4.c (tf_writev): Add test.
This patch consolidates all the preadv{64} implementation for Linux
in only one (sysdeps/unix/sysv/linux/preadv{64}.c). It also removes the
syscall from the auto-generation using assembly macros.
It was based on previous pread/pread64 consolidation patch. The new macro
SYSCALL_LL{64} is used to handle the offset argument and alias is created
for __ASSUME_OFF_DIFF_OFF64 in case of pread64.
Checked on x86_64, i386, aarch64, and powerpc64le.
* misc/Makefile (CFLAGS-preadv.c): New variable: add cancellation
required flags.
(CFLAGS-preadv64.c): Likewise.
* sysdeps/unix/sysv/linux/generic/wordsize-32/preadv.c: Remove file.
* sysdeps/unix/sysv/linux/generic/wordsize-32/preadv64.c: Likewise.
* sysdeps/unix/sysv/linux/mips/mips64/n64/preadv64.c: Likewise.
* sysdeps/unix/sysv/linux/wordsize-64/preadv.c: Likewise.
* sysdeps/unix/sysv/linux/wordsize-64/preadv64.: Likwise.
* sysdeps/unix/sysv/linux/x86_64/x32/syscalls.list (preadv): Remove
syscall from auto-generation.
* sysdeps/unix/sysv/linux/preadv.c: Rewrite implementation.
[WORDSIZE == 64] (preadv64): Remove macro.
[!PREADV] (PREADV): Likewise.
[!PREADV] (PREADV_REPLACEMENT): Likewise.
[!PREADV] (PREAD): Likewise.
[!PREADV] (OFF_T): Likewise.
[!__ASSUME_PREADV] (PREADV_REPLACEMENT): Likewise.
(LO_HI_LONG): Remove macro.
[__WORDSIZE != 64 || __ASSUME_OFF_DIFF_OFF64] (preadv): Add function.
* sysdeps/unix/sysv/linux/preadv64.c: Rewrite implementation.
(PREADV): Remove macro.
(PREADV_REPLACEMENTE): Likewise.
(PREAD): Likewise.
(OFF_T): Likewise.
(preadv64): New function.
* nptl/tst-cancel4.c (tf_preadv): Add test.
The use of __USE_KERNEL_IPV6_DEFS with ifndef is bad
practice per: https://sourceware.org/glibc/wiki/Wundef.
This change moves it to use 'if' and always define the
macro.
Please note that this is not the only problem with this
code. I have a series of fixes after this one to resolve
breakage with this code and add regression tests for it
via compile-only source testing (to be discussed in another
thread).
Unfortunately __USE_KERNEL_XATTR_DEFS is set by the kernel
and not glibc, and uses 'define', so we can't fix that yet.
This patch call _exit instead of exit in failure case for the spawned
child in Linux posix_spawn{p} implementation.
Tested on x86_64.
[BZ #20178]
* sysdeps/unix/sysv/linux/spawni.c (__spawni_child): Call _exit
on failure instead of exit.
This patch fixes wrong/missing bits from the Fix {recv,send}{m}msg
standard compliance (BZ#16919) patches:
* nptl/Makefile sets CFLAGS-oldrecvfrom.c, but there's no such file as
oldrecvfrom.c. It should be oldsendmsg.c as defined by ChangeLog.
* sysdeps/unix/sysv/linux/hppa/Versions and
sysdeps/unix/sysv/linux/i386/Versions list a symbol recvms instead of
recvmsg at version GLIBC_2.24.
* nptl/Makefile (CFLAGS-oldrecvfrom.c): Remove rule.
(CFLAGS-oldsendmsg.c): Add rule.
* sysdeps/unix/sysv/linux/hppa/Versions [libc] (GLIBC_2.24):
Correct recvmsg symbol name.
* sysdeps/unix/sysv/linux/i386/Versions [libc] (GLIBC_2.24):
Likewise.
POSIX specifies that both msghdr::msg_iovlen and msghdr::msg_controllen
to be of size int and socklen_t respectively, however Linux implements
it as a size_t. So for 64-bits architecture where sizeof of size_t is
larger than socklen_t, both sendmmsg and recvmmsg need to adjust the
mmsghdr::msg_hdr internal fields before issuing the syscall itself.
This patch fixes it by operating on the padding if it the case.
For recvmmsg, the most straightfoward case, only zero padding the fields
is suffice. However, for sendmmsg, where adjusting the buffer is out
of the contract (since it may point to a read-only data), the function
is rewritten to use sendmsg instead (which from previous patch
allocates a temporary msghdr to operate on).
Also for 64-bit ports that requires it, a new recvmmsg and sendmmsg
compat version is created (which uses size_t for both cmsghdr::cmsg_len
and internal
Tested on x86_64, i686, aarch64, armhf, and powerpc64le.
* sysdeps/unix/sysv/linux/Makefile
[$(subdir) = socket] (sysdep_routines): Add oldrecvmmsg and
oldsendmmsg.
* sysdeps/unix/sysv/linux/aarch64/libc.abilist: Add recvmmsg and
sendmmsg.
* sysdeps/unix/sysv/linux/alpha/libc.abilist: Likewise.
* sysdeps/unix/sysv/linux/ia64/libc.abilist: Likewise.
* sysdeps/unix/sysv/linux/mips/mips64/n64/libc.abilist: Likewise.
* sysdeps/sysv/linux/powerpc/powerpc64/libc-le.abilist: Likewise.
* sysdeps/unix/sysv/linux/powerpc/powerpc64/libc.abilist: Likewise.
* sysdeps/unix/sysv/linux/s390/s390-64/libc.abilist: Likewise.
* sysdeps/unix/sysv/linux/sparc/sparc64/libc.abilist: Likewise.
* sysdeps/unix/sysv/linux/tile/tilegx/tilegx64/libc.abilist:
Likewise.
* sysdeps/unix/sysv/linux/x86_64/64/libc.abilist: Likewise.
* sysdeps/unix/sysv/linux/oldrecvmmsg.c: New file.
* sysdeps/unix/sysv/linux/oldsendmmsg.c: Likewise.
* sysdeps/unix/sysv/linux/recvmmsg.c (__recvmmsg): Adjust msghdr
iovlen and controllen fields to adjust to POSIX specification.
* sysdeps/unix/sysv/linux/sendmmsg.c (__sendmmsg): Likewise.
This avoids aliasing issues with GCC 6 in -fno-strict-aliasing
mode. (With implicit padding, not all data is copied.)
This change makes it explicit that struct sockaddr_storage is
only 126 bytes large on m68k (unlike elsewhere, where we end up
with the requested 128 bytes). The new test case makes sure that
this does not happen on other architectures.
This patch updates sysdeps/unix/sysv/linux/bits/socket.h for new
constants added in Linux 4.6. AF_KCM / PF_KCM are added. SOL_KCM is
new, and I added a lot of SOL_* values postdating the last one present
in the header, since I saw no apparent reason for the set in glibc to
stop at SOL_IRDA. MSG_BATCH is added; Linux also has
MSG_SENDPAGE_NOTLAST which is not in glibc, but given the comment
starts "sendpage() internal" I presume it's correct for it not to be
in glibc.
(Note that this is a case where the Linux kernel header with userspace
relevant values is *not* a uapi header but include/linux/socket.h - I
don't know why, but at least this header, as well as uapi headers,
needs reviewing for glibc-relevant changes each release.)
Tested for x86_64 and x86 (testsuite, and that installed stripped
shared libraries are unchanged by the patch).
* sysdeps/unix/sysv/linux/bits/socket.h (PF_KCM): New macro.
(PF_MAX): Update value.
(AF_KCM): New macro.
(SOL_NETBEUI): Likewise.
(SOL_LLC): Likewise.
(SOL_DCCP): Likewise.
(SOL_NETLINK): Likewise.
(SOL_TIPC): Likewise.
(SOL_RXRPC): Likewise.
(SOL_PPPOL2TP): Likewise.
(SOL_BLUETOOTH): Likewise.
(SOL_PNPIPE): Likewise.
(SOL_RDS): Likewise.
(SOL_IUCV): Likewise.
(SOL_CAIF): Likewise.
(SOL_ALG): Likewise.
(SOL_NFC): Likewise.
(SOL_KCM): Likewise.
(MSG_BATCH): New enum value and macro.
There is no need to call the internal funtion, _Unwind_Resume, which
is defined in unwind-forcedunwind.c, via PLT.
* sysdeps/unix/sysv/linux/x86_64/pthread_cond_timedwait.S
(__condvar_cleanup2): Remove JUMPTARGET from _Unwind_Resume
call.
* sysdeps/unix/sysv/linux/x86_64/pthread_cond_wait.S
(__condvar_cleanup1): Likewise.
Add PTHREAD_UNWIND to replace JUMPTARGET(__pthread_unwind) and define
it to __GI___pthread_unwind within libpthread.
* sysdeps/unix/sysv/linux/x86_64/cancellation.S (PTHREAD_UNWIND):
New
(__pthread_unwind): Renamed to ...
(PTHREAD_UNWIND): This.
(__pthread_enable_asynccancel): Replace
JUMPTARGET(__pthread_unwind) with PTHREAD_UNWIND.
This patch adds CLONE_NEWCGROUP, new in Linux 4.6, to
sysdeps/unix/sysv/linux/bits/sched.h.
Tested for x86_64 and x86 (testsuite, and that installed stripped
shared libraries are unchanged by the patch).
* sysdeps/unix/sysv/linux/bits/sched.h [__USE_GNU]
(CLONE_NEWCGROUP): New macro.
This patch adds Q_GETNEXTQUOTA, new in Linux 4.6, to
sysdeps/unix/sysv/linux/sys/quota.h.
Tested for x86_64 and x86 (testsuite, and that installed shared
libraries are unchanged by the patch).
* sysdeps/unix/sysv/linux/sys/quota.h [_LINUX_QUOTA_VERSION >= 2]
(Q_GETNEXTQUOTA): New macro.
This patch adds support for symbol __kernel_getcpu in vDSO,
which is available with kernel 4.5.
Now sched_getcpu is using this symbol if available in mapped vDSO
by defining macro HAVE_GETCPU_VSYSCALL. If not available at runtime,
the former syscall is used.
Instead, we store the data we need from the return value of
readdir in an object of the new type struct readdir_result.
This type is independent of the layout of struct dirent.
This patch fixes the clone CLONE_VM change from 0cb313f (BZ#19957)
where the commit changed the register that contains the save flags
argument to compare with (from r28 to r29). This patch changes
back to correct register.
Tested on powerpc32 (thanks to Tulio Magno Quites Machado Filho).
* sysdeps/unix/sysv/linux/powerpc/powerpc32/clone.S (__clone): Fix
flags CLONE_VM compare.
As discussed in libc-alpha [1] current clone with CLONE_VM (without
CLONE_THREAD set) will reset the pthread pid/tid fields to -1. The
issue is since memory is shared between the parent and child it will
clobber parent's cached pid/tid leading to internal inconsistencies
if the value is not restored.
And even it is restored it may lead to racy conditions when between
set/restore a thread might invoke pthread function that validate the
pthread with INVALID_TD_P/INVALID_NOT_TERMINATED_TD_P and thus get
wrong results.
As stated in BZ19957, previously reports of this behaviour was close
with EWONTFIX due the fact usage of clone outside glibc is tricky
since glibc requires consistent internal pthread, while using clone
directly may not provide it. However since now posix_spawn uses
clone (CLONE_VM) to fixes various issues related to previous vfork
usage this issue requires fixing.
The vfork implementation also does something similar, but instead
it negates and restores only the *pid* field and functions that
might access its value know to handle such case (getpid, raise
and pthread ones that uses INVALID_TD_P/INVALID_NOT_TERMINATED_TD_P
macros that check only *tid* field). Also vfork does not call
__clone directly, instead calling either __NR_vfork or __NR_clone
directly.
So this patch removes this clone behavior by avoiding setting
the pthread pid/tid field for CLONE_VM. There is no need to
check for CLONE_THREAD, since the minimum supported kernel in all
architecture implies that CLONE_VM must be used with CLONE_THREAD,
otherwise clone returns EINVAL.
Instead of current approach of:
int clone(int (*fn)(void *), void *child_stack, int flags, ...)
[...]
if (flags & CLONE_THREAD)
goto do_syscall;
pid_t new_value;
if (flags & CLONE_VM)
new_value = -1;
else
new_value = getpid ();
THREAD_SETMEM (THREAD_SELF, pid, new_value);
THREAD_SETMEM (THREAD_SELF, tid, new_value);
do_syscall:
[...]
The new approach uses:
int clone(int (*fn)(void *), void *child_stack, int flags, ...)
[...]
if (flags & CLONE_VM)
goto do_syscall;
pid_t new_value = getpid ();
THREAD_SETMEM (THREAD_SELF, pid, new_value);
THREAD_SETMEM (THREAD_SELF, tid, new_value);
do_syscall:
[...]
It also removes the linux tst-getpid2.c test which expects the previous
behavior and instead add another clone test.
Tested on x86_64, i686, x32, powerpc64le, aarch64, armhf, s390, and
s390x. I also did limited check on mips32 and sparc64 (using the new
added test).
I also got reviews from both m68k, hppa, and tile. So I presume for
these architecture the patch works.
The fixes for alpha, microblaze, sh, ia64, and nio2 have not been
tested.
[1] https://sourceware.org/ml/libc-alpha/2016-04/msg00307.html
* sysdeps/unix/sysv/linux/Makefile [$(subdir) == nptl] (test): Remove
tst-getpid2.
(test): Add tst-clone2.
* sysdeps/unix/sysv/linux/tst-clone2.c: New file.
* sysdeps/unix/sysv/linux/aarch64/clone.S (__clone): Do not change
pid/tid fields for CLONE_VM.
* sysdeps/unix/sysv/linux/arm/clone.S: Likewise.
* sysdeps/unix/sysv/linux/i386/clone.S: Likewise.
* sysdeps/unix/sysv/linux/mips/clone.S: Likewise.
* sysdeps/unix/sysv/linux/powerpc/powerpc32/clone.S: Likewise.
* sysdeps/unix/sysv/linux/powerpc/powerpc64/clone.S: Likewise.
* sysdeps/unix/sysv/linux/s390/s390-32/clone.S: Likewise.
* sysdeps/unix/sysv/linux/s390/s390-64/clone.S: Likewise.
* sysdeps/unix/sysv/linux/sparc/sparc32/clone.S: Likewise.
* sysdeps/unix/sysv/linux/sparc/sparc64/clone.S: Likewise.
* sysdeps/unix/sysv/linux/x86_64/clone.S: Likewise.
* sysdeps/unix/sysv/linux/tst-getpid2.c: Remove file.
this patch adds the missing SOL_IUCV socket level definition
and socket options SO_IPRMDATA_MSG, SO_MSGLIMIT, SO_MSGSIZE
which can be used with get/setsockopt().
SCM_IUCV_TRGCLS is needed to send/receive ancillary data with send/recvmsg().
The defines are copied from kernel-source:
include/net/iucv/af_iucv.h
include/linux/socket.h
This patch fixes the __ALIGNMENT_{ARG,COUNT} definition for ports that
define __ASSUME_ALIGNED_REGISTER_PAIRS by including the kernel-features.h
(where it is defined if the case).
This was shown on arm with failing cases:
FAIL: debug/tst-chk1
FAIL: debug/tst-chk2
FAIL: debug/tst-chk3
FAIL: debug/tst-chk4
FAIL: debug/tst-chk5
FAIL: debug/tst-chk6
FAIL: debug/tst-lfschk1
FAIL: debug/tst-lfschk2
FAIL: debug/tst-lfschk3
FAIL: debug/tst-lfschk4
FAIL: debug/tst-lfschk5
FAIL: debug/tst-lfschk6
FAIL: posix/tst-preadwrite
FAIL: posix/tst-preadwrite64
The patches fixes it. Tested on armhf.
* sysdeps/unix/sysv/linux/sysdep.h: Include kernel-features.h.
The overloading approach in the W* macros was incompatible with
integer expressions of a type different from int. Applications
using union wait and these macros will have to migrate to the
POSIX-specified int status type.
This patch adds support for using the implementations of gettimeofday()
and clock_gettime() provided by the kernel in the VDSO. The VDSO will
always provide clock_gettime() as CLOCK_{REALTIME,MONOTONIC}_COARSE can
be implemented regardless of platform. CLOCK_{REALTIME,MONOTONIC}, along
with gettimeofday(), are only implemented on platforms which make use of
either the CP0 count or GIC as their clocksource. On other platforms,
the VDSO does not provide the __vdso_gettimeofday symbol, as it is
never useful.
The VDSO functions return ENOSYS when they encounter an unsupported
request, in which case glibc should fall back to the standard syscall.
Tested with upstream kernel 4.5 and QEMU emulating Malta.
./vdsotest gettimeofday bench
gettimeofday: syscall: 1021 nsec/call
gettimeofday: libc: 262 nsec/call
gettimeofday: vdso: 174 nsec/call
* sysdeps/unix/sysv/linux/mips/Makefile (sysdep_routines):
Include dl-vdso.
* sysdeps/unix/sysv/linux/mips/Versions: Add
__vdso_clock_gettime.
* sysdeps/unix/sysv/linux/mips/init-first.c: New file.
* sysdeps/unix/sysv/linux/mips/libc-vdso.h: New file.
* sysdeps/unix/sysv/linux/mips/mips32/sysdep.h:
(INTERNAL_VSYSCALL_CALL): Define to be compatible with MIPS
definitions of INTERNAL_SYSCALL_{ERROR_P,ERRNO}.
(HAVE_CLOCK_GETTIME_VSYSCALL): Define.
(HAVE_GETTIMEOFDAY_VSYSCALL): Define.
* sysdeps/unix/sysv/linux/mips/mips64/n32/sysdep.h: Likewise.
* sysdeps/unix/sysv/linux/mips/mips64/n64/sysdep.h: Likewise.
This patch consolidates all the pwrite/pwrite64 implementation for Linux
in only one (sysdeps/unix/sysv/linux/pwrite{64}.c). It also removes the
syscall from the auto-generation using assembly macros.
For pwrite{64} offset argument placement the new SYSCALL_LL{64} macro
is used. For pwrite ports that do not define __NR_pwrite will use
__NR_pwrite64 and for pwrite64 ports that dot define __NR_pwrite64 will
use __NR_pwrite for the syscall.
Checked on x86_64, x32, i386, aarch64, and ppc64le.
* sysdeps/unix/sysv/linux/arm/pwrite.c: Remove file.
* sysdeps/unix/sysv/linux/arm/pwrite64.c: Likewise.
* sysdeps/unix/sysv/linux/generic/wordsize-32/pwrite.c: Likewise.
* sysdeps/unix/sysv/linux/generic/wordsize-32/pwrite64.c: Likewise.
* sysdeps/unix/sysv/linux/powerpc/powerpc32/pwrite.c: Likewise.
* sysdeps/unix/sysv/linux/powerpc/powerpc32/pwrite64.c: Likewise.
* sysdeps/unix/sysv/linux/wordsize-64/pwrite64.c: Likewise.
* sysdeps/unix/sysv/linux/wordsize-64/syscalls.list (prite): Remove
syscalls generation.
* sysdeps/unix/sysv/linux/powerpc/powerpc32/sysdep.h
[__NR_pwrite64] (__NR_write): Remove define.
* sysdeps/unix/sysv/linux/powerpc/powerpc64/sysdep.h
[__NR_pwrite64] (__NR_write): Remove define.
* sysdeps/unix/sysv/linux/pwrite.c [__NR_pwrite64] (__NR_pwrite):
Remove define.
(__libc_pwrite): Use SYSCALL_LL macro on offset argument.
* sysdeps/unix/sysv/linux/pwrite64.c [__NR_pwrite64] (__NR_pwrite):
Remove define.
(__libc_pwrite64): Use SYSCALL_LL64 macro on offset argument.
* sysdeps/unix/sysv/linux/sh/pwrite.c: Rewrite using default
Linux implementation as base.
* sysdeps/unix/sysv/linux/sh/pwrite64.c: Likewise.
* sysdeps/unix/sysv/linux/mips/pwrite.c: Likewise.
* sysdeps/unix/sysv/linux/mips/pwrite64.c: Likewise.
This patch consolidates all the pread/pread64 implementation for Linux
in only one (sysdeps/unix/sysv/linux/pread.c). It also removes the
syscall from the auto-generation using assembly macros.
For pread{64} offset argument placement the new SYSCALL_LL{64} macro
is used. For pread ports that do not define __NR_pread will use
__NR_pread64 and for pread64 ports that dot define __NR_pread64 will
use __NR_pread for the syscall.
Checked on x86_64, x32, i386, aarch64, and ppc64le.
* sysdeps/unix/sysv/linux/arm/pread.c: Remove file.
* sysdeps/unix/sysv/linux/arm/pread64.c: Likewise.
* sysdeps/unix/sysv/linux/generic/wordsize-32/pread.c: Likewise.
* sysdeps/unix/sysv/linux/generic/wordsize-32/pread64.c: Likewise.
* sysdeps/unix/sysv/linux/powerpc/powerpc32/pread.c: Likewise,
* sysdeps/unix/sysv/linux/powerpc/powerpc32/pread64.c: Likewise.
* sysdeps/unix/sysv/linux/wordsize-64/pread64.c: Likewise.
* sysdeps/unix/sysv/linux/wordsize-64/syscalls.list (pread): Remove
syscall generation.
* sysdeps/unix/sysv/linux/powerpc/powerpc32/sysdep.h
[__NR_pread64] (__NR_pread): Remove define.
* sysdeps/unix/sysv/linux/powerpc/powerpc64/sysdep.h:
[__NR_pread64] (__NR_pread): Likewise.
* sysdeps/unix/sysv/linux/pread.c [__NR_pread64] (__NR_pread): Remove
define.
(__libc_pread): Use SYSCALL_LL macro on offset argument.
* sysdeps/unix/sysv/linux/pread64.c [__NR_pread64] (__NR_pread):
Remove define.
(__libc_pread64): Use SYSCALL_LL64 macro on offset argument.
* sysdeps/unix/sysv/linux/sh/pread.c: Rewrite using default
Linux implementation as base.
* sysdeps/unix/sysv/linux/sh/pread64.c: Likewise.
* sysdeps/unix/sysv/linux/mips/pread.c: Likewise.
* sysdeps/unix/sysv/linux/mips/pread64.c: Likewise.
This patch add three new macros (SYSCALL_LL, SYSCALL_LL64, and
__ASSUME_WORDSIZE64_ILP32) to use along with off_t and off64_t argument
syscalls. The rationale for this change is:
1. Remove multiple implementations for the same syscall for different
architectures (for instance, pread have 6 different implementations).
2. Also remove the requirement to use syscall wrappers for cancellable
entrypoints.
The macro usage should be used along __ALIGNMENT_ARG to follow ABI constrains
for architecture where it applies. For instance, pread can be rewritten as:
return SYSCALL_CANCEL (pread, fd, buf, count,
__ALIGNMENT_ARG SYSCALL_LL (offset));
Another macro, SYSCALL_LL64, is provided for off64_t. The macro
__ASSUME_WORDSIZE64_ILP32 is used by the ABI to define is uses 64-bit register
even if ABI is ILP32 (for instance x32 and mips64-n32).
The changes itself are not currently used in any implementation, so no
code change is expected.
* sysdeps/unix/sysv/linux/generic/sysdep.h (__ALIGNMENT_ARG): Move
definition.
(__ALIGNMENT_COUNT): Likewise.
* sysdeps/unix/sysv/linux/sysdep.h (__ALIGNMENT_ARG): To here.
(__ALIGNMENT_COUNT): Likewise.
(SYSCALL_LL): New define.
(SYSCALL_LL64): Likewise.
* sysdeps/unix/sysv/linux/mips/kernel-features.h:
[_MIPS_SIM == _ABIO32] (__ASSUME_WORDSIZE64_ILP32): Define.
* sysdeps/unix/sysv/linux/x86_64/kernel-features.h:
[ILP32] (__ASUME_WORDSIZE64_ILP32): Likewise.
This patch defines __ASSUME_ALIGNED_REGISTER_PAIRS for the missing
ports that require 64-bit value (e.g., long long) to be aligned to
an even register pair in argument passing.
No code change is expected, tested with builds for powerpc32,
mips-o32, and armhf.
* sysdeps/unix/sysv/linux/arm/kernel-features.h
(__ASSUME_ALIGNED_REGISTER_PAIRS): Define.
* sysdeps/unix/sysv/linux/mips/kernel-features.h
[_MIPS_SIM == _ABIO32] (__ASSUME_ALIGNED_REGISTER_PAIRS): Likewise.
* sysdeps/unix/sysv/linux/powerpc/kernel-features.h
[!__powerpc64__] (__ASSUME_ALIGNED_REGISTER_PAIRS): Likewise.
bits/termios.h (various versions under sysdeps/unix/sysv/linux)
defines XCASE if defined __USE_MISC || defined __USE_XOPEN. This
macro was removed in the 2001 edition of POSIX, and is not otherwise
reserved, so should not be defined for 2001 and later versions of
POSIX. This patch fixes the conditions accordingly (leaving the macro
defined for __USE_MISC, so still in the default namespace).
Tested for x86_64 and x86 (testsuite, and that installed shared
libraries are unchanged by the patch).
[BZ #19925]
* sysdeps/unix/sysv/linux/alpha/bits/termios.h (XCASE): Do not
define if [!__USE_MISC && __USE_XOPEN2K].
* sysdeps/unix/sysv/linux/bits/termios.h (XCASE): Likewise.
* sysdeps/unix/sysv/linux/mips/bits/termios.h (XCASE): Likewise.
* sysdeps/unix/sysv/linux/powerpc/bits/termios.h (XCASE):
Likewise.
* sysdeps/unix/sysv/linux/sparc/bits/termios.h (XCASE): Likewise.
* conform/Makefile (test-xfail-XOPEN2K/termios.h/conform): Remove
variable.
(test-xfail-XOPEN2K8/termios.h/conform): Likewise.
MicroBlaze has a special version of futimesat.c because it gained the
futimesat syscall later than other non-asm-generic architectures. Now
the minimum kernel is recent enough that this syscall can always be
assumed to be present for MicroBlaze, so this patch removes the
special version and the __ASSUME_FUTIMESAT macro, resulting in the
sysdeps/unix/sysv/linux/futimesat.c version being used.
Untested.
* sysdeps/unix/sysv/linux/microblaze/kernel-features.h
(__ASSUME_FUTIMESAT): Remove macro.
* sysdeps/unix/sysv/linux/microblaze/futimesat.c: Remove file.
<sys/personality.h> is out of sync with kernel headers, missing the
UNAME26, FDPIC_FUNCPTRS and PER_LINUX_FDPIC entries. Fix that.
Changelog:
* sysdeps/unix/sysv/linux/sys/personality.h (UNAME26, FDPIC_FUNCPTRS,
PER_LINUX_FDPIC): Add.
With the 2.6.32 minimum kernel on x86 and 3.2 on other architectures,
__NR_utimensat is always defined.
Changelog:
* sysdeps/unix/sysv/linux/futimens.c (futimens) [__NR_utimensat]:
Make code unconditional.
[!__NR_utimensat]: Remove conditional code.
* sysdeps/unix/sysv/linux/lutimes.c (lutimes) [__NR_utimensat]:
Make code unconditional.
[!__NR_utimensat]: Remove conditional code.
* sysdeps/unix/sysv/linux/utimensat.c (utimensat) [__NR_utimensat]:
Make code unconditional.
[!__NR_utimensat]: Remove conditional code.
With the 2.6.32 minimum kernel on x86 and 3.2 on other architectures,
__NR_openat is always defined.
Changelog:
* sysdeps/unix/sysv/linux/dl-openat64.c (openat64) [__NR_openat]:
Make code unconditional.
The x86-specific versions of both pthread_cond_wait and
pthread_cond_timedwait have (in their fall-back-to-futex-wait slow
paths) calls to __pthread_mutex_cond_lock_adjust followed by
__pthread_mutex_unlock_usercnt, which load the parameters before the
first call but then assume that the first parameter, in %eax, will
survive unaffected. This happens to have been true before now, but %eax
is a call-clobbered register, and this assumption is not safe: it could
change at any time, at GCC's whim, and indeed the stack-protector canary
checking code clobbers %eax while checking that the canary is
uncorrupted.
So reload %eax before calling __pthread_mutex_unlock_usercnt. (Do this
unconditionally, even when stack-protection is not in use, because it's
the right thing to do, it's a slow path, and anything else is dicing
with death.)
* sysdeps/unix/sysv/linux/i386/pthread_cond_timedwait.S: Reload
call-clobbered %eax on retry path.
* sysdeps/unix/sysv/linux/i386/pthread_cond_wait.S: Likewise.
This patch removes the __ASSUME_GETDENTS64_SYSCALL macro, as its
definition is constant given the new kernel version requirements (and
was constant anyway before those requirements except for MIPS n32).
Note that the "#ifdef __NR_getdents64" conditional *is* still needed,
because MIPS n64 only has the getdents syscall (being a 64-bit ABI,
that syscall is 64-bit; the difference between the two on 64-bit
architectures is where d_type goes). If MIPS n64 were to gain the
getdents64 syscall and we wanted to use it conditionally on the kernel
version at runtime we'd have to revert this patch, but I think that's
unlikely (and in any case, we could follow the simpler approach of
undefining __NR_getdents64 if the syscall can't be assumed, just like
we do for accept4 / recvmmsg / sendmmsg syscalls on architectures
where socketcall support came first).
Most of the getdents.c changes are reindentation.
Tested for x86_64 and x86 that installed stripped shared libraries are
unchanged by the patch.
* sysdeps/unix/sysv/linux/kernel-features.h
(__ASSUME_GETDENTS64_SYSCALL): Remove macro.
* sysdeps/unix/sysv/linux/getdents.c
[!__ASSUME_GETDENTS64_SYSCALL]: Remove conditional code.
[!have_no_getdents64_defined]: Likewise.
(__GETDENTS): Remove __have_no_getdents64 conditional.
Current Linux kernel version requirements mean the signalfd4 syscall
can always be assumed to be available. This patch removes
__ASSUME_SIGNALFD4 and associated conditionals.
Tested for x86_64 and x86 that installed stripped shared libraries are
unchanged by the patch.
* sysdeps/unix/sysv/linux/kernel-features.h (__ASSUME_SIGNALFD4):
Remove macro.
* sysdeps/unix/sysv/linux/signalfd.c: Do not include
<kernel-features.h>.
(signalfd) [__NR_signalfd4]: Make code unconditional.
(signalfd) [!__ASSUME_SIGNALFD4]: Remove conditional code.
This patch fixes the implicit check style add in 2a69f853c for the
general convention one.
Checked on x86_64.
* sysdeps/unix/sysv/linux/spawni.c (__spawnix): Fix implict checks
style.
When PLT may be used, JUMPTARGET should be used instead calling the
function directly.
* sysdeps/unix/sysv/linux/x86_64/cancellation.S
(__pthread_enable_asynccancel): Use JUMPTARGET to call
__pthread_unwind.
* sysdeps/unix/sysv/linux/x86_64/pthread_cond_timedwait.S
(__condvar_cleanup2): Use JUMPTARGET to call _Unwind_Resume.
* sysdeps/unix/sysv/linux/x86_64/pthread_cond_wait.S
(__condvar_cleanup1): Likewise.
Current Linux posix_spawn spawn do not test if the pid argument is
valid before trying to update it for success case. This patch fixes
it.
Tested on x86_64 and i686.
* sysdeps/unix/sysv/linux/spawni.c (__spawnix): Fix invalid memory
access where posix_spawn success and pid argument is null.
* posix/tst-spawn.c (do_test): Add posix_spawn null pid argument for
success case.
