glibc/sysdeps/unix
Stefan Liebler 403b4feb22 Fix race in pthread_mutex_lock while promoting to PTHREAD_MUTEX_ELISION_NP [BZ #23275]
The race leads either to pthread_mutex_destroy returning EBUSY
or triggering an assertion (See description in bugzilla).

This patch is fixing the race by ensuring that the elision path is
used in all cases if elision is enabled by the GLIBC_TUNABLES framework.

The __kind variable in struct __pthread_mutex_s is accessed concurrently.
Therefore we are now using the atomic macros.

The new testcase tst-mutex10 is triggering the race on s390x and intel.
Presumably also on power, but I don't have access to a power machine
with lock-elision. At least the code for power is the same as on the other
two architectures.

ChangeLog:

	[BZ #23275]
	* nptl/tst-mutex10.c: New File.
	* nptl/Makefile (tests): Add tst-mutex10.
	(tst-mutex10-ENV): New variable.
	* sysdeps/unix/sysv/linux/s390/force-elision.h: (FORCE_ELISION):
	Ensure that elision path is used if elision is available.
	* sysdeps/unix/sysv/linux/powerpc/force-elision.h (FORCE_ELISION):
	Likewise.
	* sysdeps/unix/sysv/linux/x86/force-elision.h: (FORCE_ELISION):
	Likewise.
	* nptl/pthreadP.h (PTHREAD_MUTEX_TYPE, PTHREAD_MUTEX_TYPE_ELISION)
	(PTHREAD_MUTEX_PSHARED): Use atomic_load_relaxed.
	* nptl/pthread_mutex_consistent.c (pthread_mutex_consistent): Likewise.
	* nptl/pthread_mutex_getprioceiling.c (pthread_mutex_getprioceiling):
	Likewise.
	* nptl/pthread_mutex_lock.c (__pthread_mutex_lock_full)
	(__pthread_mutex_cond_lock_adjust): Likewise.
	* nptl/pthread_mutex_setprioceiling.c (pthread_mutex_setprioceiling):
	Likewise.
	* nptl/pthread_mutex_timedlock.c (__pthread_mutex_timedlock): Likewise.
	* nptl/pthread_mutex_trylock.c (__pthread_mutex_trylock): Likewise.
	* nptl/pthread_mutex_unlock.c (__pthread_mutex_unlock_full): Likewise.
	* sysdeps/nptl/bits/thread-shared-types.h (struct __pthread_mutex_s):
	Add comments.
	* nptl/pthread_mutex_destroy.c (__pthread_mutex_destroy):
	Use atomic_load_relaxed and atomic_store_relaxed.
	* nptl/pthread_mutex_init.c (__pthread_mutex_init):
	Use atomic_store_relaxed.
2018-10-17 12:23:04 +02:00
..
alpha Update copyright dates with scripts/update-copyrights. 2018-01-01 00:32:25 +00:00
arm Update copyright dates with scripts/update-copyrights. 2018-01-01 00:32:25 +00:00
bsd hurd: Avoid some PLTs in libc and librt 2018-04-02 19:07:52 +00:00
i386 Update copyright dates with scripts/update-copyrights. 2018-01-01 00:32:25 +00:00
inet Switch IDNA implementation to libidn2 [BZ #19728] [BZ #19729] [BZ #22247] 2018-05-23 15:27:24 +02:00
mips Update copyright dates with scripts/update-copyrights. 2018-01-01 00:32:25 +00:00
powerpc Update copyright dates with scripts/update-copyrights. 2018-01-01 00:32:25 +00:00
sh Update copyright dates with scripts/update-copyrights. 2018-01-01 00:32:25 +00:00
sysv/linux Fix race in pthread_mutex_lock while promoting to PTHREAD_MUTEX_ELISION_NP [BZ #23275] 2018-10-17 12:23:04 +02:00
x86_64 Update copyright dates with scripts/update-copyrights. 2018-01-01 00:32:25 +00:00
clock_gettime.c Update copyright dates with scripts/update-copyrights. 2018-01-01 00:32:25 +00:00
clock_nanosleep.c hurd: Avoid some PLTs in libc and librt 2018-04-02 19:07:52 +00:00
clock_settime.c Update copyright dates with scripts/update-copyrights. 2018-01-01 00:32:25 +00:00
confstr.h
get_child_max.c Update copyright dates with scripts/update-copyrights. 2018-01-01 00:32:25 +00:00
getlogin_r.c Update copyright dates with scripts/update-copyrights. 2018-01-01 00:32:25 +00:00
getlogin.c Update copyright dates with scripts/update-copyrights. 2018-01-01 00:32:25 +00:00
getpagesize.c Update copyright dates with scripts/update-copyrights. 2018-01-01 00:32:25 +00:00
grantpt.c Update copyright dates with scripts/update-copyrights. 2018-01-01 00:32:25 +00:00
ifreq.c Update copyright dates with scripts/update-copyrights. 2018-01-01 00:32:25 +00:00
Implies
make-syscalls.sh Make llseek a compat symbol (bug 18471). 2018-05-22 15:44:01 +00:00
Makefile Update copyright dates with scripts/update-copyrights. 2018-01-01 00:32:25 +00:00
pt-fcntl.c Fix Linux fcntl OFD locks for non-LFS architectures (BZ#20251) 2018-06-26 13:22:53 -03:00
s-proto-cancel.S
s-proto.S
setxid.h
sockatmark.c Update copyright dates with scripts/update-copyrights. 2018-01-01 00:32:25 +00:00
stime.c Update copyright dates with scripts/update-copyrights. 2018-01-01 00:32:25 +00:00
syscall-template.S Update copyright dates with scripts/update-copyrights. 2018-01-01 00:32:25 +00:00
syscall.S Update copyright dates with scripts/update-copyrights. 2018-01-01 00:32:25 +00:00
syscalls.list posix: Consolidate Linux fsync syscall 2017-05-18 18:06:47 -03:00
sysdep.h nptl: Add C11 threads thrd_* functions 2018-07-24 14:06:45 -03:00