diff options
author | Samuel Thibault <samuel.thibault@ens-lyon.org> | 2020-06-07 02:03:45 +0000 |
---|---|---|
committer | Samuel Thibault <samuel.thibault@ens-lyon.org> | 2020-06-07 13:35:54 +0200 |
commit | d6d74ec16c77126c59db264ebfa04d08d5b4c5c0 (patch) | |
tree | 95fded09b6a9d8ce35273d43c3f8e3d960bd0554 /sysdeps/pthread/tst-create-detached.c | |
parent | be22a151f3e2c2e4b9127d4fa30b269f30a7ea2e (diff) | |
download | glibc-d6d74ec16c77126c59db264ebfa04d08d5b4c5c0.tar.gz glibc-d6d74ec16c77126c59db264ebfa04d08d5b4c5c0.tar.xz glibc-d6d74ec16c77126c59db264ebfa04d08d5b4c5c0.zip |
htl: Enable more tests
* htl/Makefile: Remove rules adding libpthread.so and libpthread.a to link lines. * nptl/Makefile: Move rules adding libpthread.so and libpthread.a to link lines to... * sysdeps/pthread/Makefile: ... here. * nptl/eintr.c, tst-align.c tst-align3.c tst-atfork1.c tst-backtrace1.c tst-bad-schedattr.c tst-cancel-self-canceltype.c tst-cancel-self-cleanup.c tst-cancel-self-testcancel.c tst-cancel1.c tst-cancel10.c tst-cancel12.c tst-cancel14.c tst-cancel15.c tst-cancel18.c tst-cancel19.c tst-cancel2.c tst-cancel22.c tst-cancel23.c tst-cancel26.c tst-cancel27.c tst-cancel28.c tst-cancel3.c tst-cancel8.c tst-cancelx1.c tst-cancelx10.c tst-cancelx12.c tst-cancelx14.c tst-cancelx15.c tst-cancelx18.c tst-cancelx2.c tst-cancelx3.c tst-cancelx8.c tst-cleanup0.c tst-cleanup0.expect tst-cleanup1.c tst-cleanup2.c tst-cleanup3.c tst-cleanupx0.c tst-cleanupx0.expect tst-cleanupx1.c tst-cleanupx2.c tst-cleanupx3.c tst-clock1.c tst-create-detached.c tst-detach1.c tst-eintr2.c tst-eintr3.c tst-eintr4.c tst-eintr5.c tst-exec1.c tst-exec2.c tst-exec3.c tst-exit1.c tst-exit2.c tst-exit3.c tst-flock1.c tst-fork1.c tst-fork2.c tst-fork3.c tst-fork4.c tst-getpid3.c tst-kill1.c tst-kill2.c tst-kill3.c tst-kill4.c tst-kill5.c tst-kill6.c tst-locale1.c tst-locale2.c tst-memstream.c tst-popen1.c tst-raise1.c tst-sem5.c tst-setuid3.c tst-signal4.c tst-signal5.c tst-signal6.c tst-signal8.c tst-stack1.c tst-stdio1.c tst-stdio2.c tst-sysconf.c tst-tls1.c tst-tls2.c tst-tsd1.c tst-tsd2.c tst-tsd5.c tst-tsd6.c tst-umask1.c tst-unload.c tst-unwind-thread.c tst-vfork1.c tst-vfork1x.c tst-vfork2.c tst-vfork2x.c: Move tests to... * sysdeps/pthread: ... here. Rename tst-popen1.c -> tst-pt-popen1.c tst-align.c -> tst-pt-align.c tst-align3.c -> tst-pt-align3.c tst-sysconf.c -> tst-pt-sysconf.c tst-tls1.c -> tst-pt-tls1.c tst-tls2.c -> tst-pt-tls2.c tst-vfork1.c -> tst-pt-vfork1.c tst-vfork2.c -> tst-pt-vfork2.c to avoid conflicting with libio/tst-popen1.c, elf/tst-align.c, posix/tst-sysconf.c, elf/tst-tls1.c, elf/tst-tls2.c, posix/tst-vfork1.c, posix/tst-vfork2.c. * nptl/Makefile: Move corresponding tests references and special rules to... * sysdeps/pthread/Makefile: ... here. * sysdeps/pthread/tst-stack1.c (do_test): Do not clamp stack size to PTHREAD_STACK_MIN if not defined. Tested on linux-x86_64 and hurd-i386
Diffstat (limited to 'sysdeps/pthread/tst-create-detached.c')
-rw-r--r-- | sysdeps/pthread/tst-create-detached.c | 138 |
1 files changed, 138 insertions, 0 deletions
diff --git a/sysdeps/pthread/tst-create-detached.c b/sysdeps/pthread/tst-create-detached.c new file mode 100644 index 0000000000..cd79c68908 --- /dev/null +++ b/sysdeps/pthread/tst-create-detached.c @@ -0,0 +1,138 @@ +/* Bug 20116: Test rapid creation of detached threads. + Copyright (C) 2017-2020 Free Software Foundation, Inc. + This file is part of the GNU C Library. + + The GNU C Library is free software; you can redistribute it and/or + modify it under the terms of the GNU Lesser General Public + License as published by the Free Software Foundation; either + version 2.1 of the License, or (at your option) any later version. + + The GNU C Library is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + Lesser General Public License for more details. + + You should have received a copy of the GNU Lesser General Public + License along with the GNU C Library; see the file COPYING.LIB. If + not, see <https://www.gnu.org/licenses/>. */ + +/* The goal of the test is to trigger a failure if the parent touches + any part of the thread descriptor after the detached thread has + exited. We test this by creating many detached threads with large + stacks. The stacks quickly fill the the stack cache and subsequent + threads will start to cause the thread stacks to be immediately + unmapped to satisfy the stack cache max. With the stacks being + unmapped the parent's read of any part of the thread descriptor will + trigger a segfault. That segfault is what we are trying to cause, + since any segfault is a defect in the implementation. */ + +#include <pthread.h> +#include <stdio.h> +#include <errno.h> +#include <unistd.h> +#include <stdbool.h> +#include <sys/resource.h> +#include <support/xthread.h> + +/* Number of threads to create. */ +enum { threads_to_create = 100000 }; + +/* Number of threads which should spawn other threads. */ +enum { creator_threads = 2 }; + +/* Counter of threads created so far. This is incremented by all the + running creator threads. */ +static unsigned threads_created; + +/* Thread callback which does nothing, so that the thread exits + immediatedly. */ +static void * +do_nothing (void *arg) +{ + return NULL; +} + +/* Attribute indicating that the thread should be created in a detached + fashion. */ +static pthread_attr_t detached; + +/* Barrier to synchronize initialization. */ +static pthread_barrier_t barrier; + +static void * +creator_thread (void *arg) +{ + int ret; + xpthread_barrier_wait (&barrier); + + while (true) + { + pthread_t thr; + /* Thread creation will fail if the kernel does not free old + threads quickly enough, so we do not report errors. */ + ret = pthread_create (&thr, &detached, do_nothing, NULL); + if (ret == 0 && __atomic_add_fetch (&threads_created, 1, __ATOMIC_SEQ_CST) + >= threads_to_create) + break; + } + + return NULL; +} + +static int +do_test (void) +{ + /* Limit the size of the process, so that memory allocation will + fail without impacting the entire system. */ + { + struct rlimit limit; + if (getrlimit (RLIMIT_AS, &limit) != 0) + { + printf ("FAIL: getrlimit (RLIMIT_AS) failed: %m\n"); + return 1; + } + /* This limit, 800MB, is just a heuristic. Any value can be + picked. */ + long target = 800 * 1024 * 1024; + if (limit.rlim_cur == RLIM_INFINITY || limit.rlim_cur > target) + { + limit.rlim_cur = target; + if (setrlimit (RLIMIT_AS, &limit) != 0) + { + printf ("FAIL: setrlimit (RLIMIT_AS) failed: %m\n"); + return 1; + } + } + } + + xpthread_attr_init (&detached); + + xpthread_attr_setdetachstate (&detached, PTHREAD_CREATE_DETACHED); + + /* A large thread stack seems beneficial for reproducing a race + condition in detached thread creation. The goal is to reach the + limit of the runtime thread stack cache such that the detached + thread's stack is unmapped after exit and causes a segfault when + the parent reads the thread descriptor data stored on the the + unmapped stack. */ + xpthread_attr_setstacksize (&detached, 16 * 1024 * 1024); + + xpthread_barrier_init (&barrier, NULL, creator_threads); + + pthread_t threads[creator_threads]; + + for (int i = 0; i < creator_threads; ++i) + threads[i] = xpthread_create (NULL, creator_thread, NULL); + + for (int i = 0; i < creator_threads; ++i) + xpthread_join (threads[i]); + + xpthread_attr_destroy (&detached); + + xpthread_barrier_destroy (&barrier); + + return 0; +} + +#define TIMEOUT 100 +#include <support/test-driver.c> |