From patchwork Mon Aug 23 19:50:29 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Adhemerval Zanella X-Patchwork-Id: 44746 Return-Path: X-Original-To: patchwork@sourceware.org Delivered-To: patchwork@sourceware.org Received: from server2.sourceware.org (localhost [IPv6:::1]) by sourceware.org (Postfix) with ESMTP id 8E7B73858404 for ; Mon, 23 Aug 2021 19:51:22 +0000 (GMT) DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org 8E7B73858404 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=sourceware.org; s=default; t=1629748282; bh=F92NoCK/aYElRSjKmahCHLvBWRjgNS+/WYDTqXdMGH0=; h=To:Subject:Date:In-Reply-To:References:List-Id:List-Unsubscribe: List-Archive:List-Post:List-Help:List-Subscribe:From:Reply-To:Cc: From; b=UkB7iUaMc0LXvRurTPa1MLVMzxrCzGFcN9ZEzpGCIjMlXrOa+1P1pyePKwfAgSFBQ DI/7vAPRobPVzxv3PippD/qOV0LntCFnio1UUgl9KZisX/U7BvT9FfCCDH8+PZtwH1 Xar3/qc4t9/FqnGAiYrdVVCMKvxBCJFWmnVEKMLE= X-Original-To: libc-alpha@sourceware.org Delivered-To: libc-alpha@sourceware.org Received: from mail-qk1-x734.google.com (mail-qk1-x734.google.com [IPv6:2607:f8b0:4864:20::734]) by sourceware.org (Postfix) with ESMTPS id B33E53858C3B for ; Mon, 23 Aug 2021 19:50:52 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.4.1 sourceware.org B33E53858C3B Received: by mail-qk1-x734.google.com with SMTP id b64so6686046qkg.0 for ; Mon, 23 Aug 2021 12:50:52 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=F92NoCK/aYElRSjKmahCHLvBWRjgNS+/WYDTqXdMGH0=; b=ZDcdphhGf9e8eCQSQAMUTTNho3QsrVA4T0l/9B622M2lbtdGh+r/Gb7X2I7gJ3cE7e L+lgYwSrA67+sMKWNdTvMel5cyObfTu8suhOQAIOogxtD3vtXMfzbE+IdGBwt3h5v+W9 YwK802IaECcYjt1yDiic8DCx+6ZpktO/DIM2xWv6RTyKO1yWu6siy8aI4McgIBA99vXY NgiFJMBH4a+gCOrPkNN2doF68zLMZVvcScCZGrmrtvd8Qs7JIlwD4z+9naTAOdUuaspO eLIuogn11o3+z1SxZ8SgE7tRcZWiIseaTyqiEkU6UdI3Z0xP4aU8EK9/t1ng9WP/th0K uKEQ== X-Gm-Message-State: AOAM530kMNBSGboaN8Sv83xvvhmlxBQg4BnMDSEwy2pmOlc1FwuSC72F xI7ketTI6m7g8kq3/q1Bylias94z52fvrQ== X-Google-Smtp-Source: ABdhPJxOCwCWVRuWUDTRZa5UeOTa7oGWPBx3JgXKNE5xO5jjOQxD0RSWQ6zQj9imC+t3XH+URqDrkQ== X-Received: by 2002:a05:620a:2094:: with SMTP id e20mr22474082qka.171.1629748252171; Mon, 23 Aug 2021 12:50:52 -0700 (PDT) Received: from birita.. ([2804:431:c7ca:cd83:c38b:b50d:5d9a:43d4]) by smtp.gmail.com with ESMTPSA id s10sm9210935qko.134.2021.08.23.12.50.51 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 23 Aug 2021 12:50:51 -0700 (PDT) To: libc-alpha@sourceware.org Subject: [PATCH v2 01/19] nptl: Fix tst-cancel7 and tst-cancelx7 race condition (BZ #14232) Date: Mon, 23 Aug 2021 16:50:29 -0300 Message-Id: <20210823195047.543237-2-adhemerval.zanella@linaro.org> X-Mailer: git-send-email 2.30.2 In-Reply-To: <20210823195047.543237-1-adhemerval.zanella@linaro.org> References: <20210823195047.543237-1-adhemerval.zanella@linaro.org> MIME-Version: 1.0 X-Spam-Status: No, score=-11.9 required=5.0 tests=BAYES_00, DKIM_SIGNED, DKIM_VALID, DKIM_VALID_AU, DKIM_VALID_EF, GIT_PATCH_0, RCVD_IN_DNSWL_NONE, SPF_HELO_NONE, SPF_PASS, TXREP autolearn=ham autolearn_force=no version=3.4.4 X-Spam-Checker-Version: SpamAssassin 3.4.4 (2020-01-24) on server2.sourceware.org X-BeenThere: libc-alpha@sourceware.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Libc-alpha mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-Patchwork-Original-From: Adhemerval Zanella via Libc-alpha From: Adhemerval Zanella Reply-To: Adhemerval Zanella Cc: Florian Weimer Errors-To: libc-alpha-bounces+patchwork=sourceware.org@sourceware.org Sender: "Libc-alpha" A mapped temporary file and a semaphore is used to synchronize the pid information on the created file, the semaphore is updated once the file contents is flushed. Checked on x86_64-linux-gnu. Reviewed-by: Florian Weimer --- nptl/tst-cancel7.c | 114 ++++++++++++++++++++++----------------------- 1 file changed, 57 insertions(+), 57 deletions(-) diff --git a/nptl/tst-cancel7.c b/nptl/tst-cancel7.c index 7a1870ac74..82ac9b9aac 100644 --- a/nptl/tst-cancel7.c +++ b/nptl/tst-cancel7.c @@ -18,44 +18,48 @@ #include #include -#include +#include #include -#include #include -#include -#include -#include - +#include +#include + +#include +#include +#include +#include +#include #include -const char *command; -const char *pidfile; -char pidfilename[] = "/tmp/tst-cancel7-XXXXXX"; +static const char *command; +static const char *pidfile; +static const char *semfile; +static char *pidfilename; +static char *semfilename; + +static sem_t *sem; static void * tf (void *arg) { - const char *args = " --direct --pidfile "; - char *cmd = alloca (strlen (command) + strlen (args) - + strlen (pidfilename) + 1); - - strcpy (stpcpy (stpcpy (cmd, command), args), pidfilename); + char *cmd = xasprintf ("%s --direct --sem %s --pidfile %s", + command, semfilename, pidfilename); system (cmd); /* This call should never return. */ return NULL; } - static void sl (void) { - FILE *f = fopen (pidfile, "w"); - if (f == NULL) - exit (1); + FILE *f = xfopen (pidfile, "w"); fprintf (f, "%lld\n", (long long) getpid ()); fflush (f); + if (sem_post (sem) != 0) + FAIL_EXIT1 ("sem_post: %m"); + struct flock fl = { .l_type = F_WRLCK, @@ -64,7 +68,7 @@ sl (void) .l_len = 1 }; if (fcntl (fileno (f), F_SETLK, &fl) != 0) - exit (1); + FAIL_EXIT1 ("fcntl (F_SETFL): %m"); sigset_t ss; sigfillset (&ss); @@ -76,57 +80,57 @@ sl (void) static void do_prepare (int argc, char *argv[]) { + int semfd; + if (semfile == NULL) + semfd = create_temp_file ("tst-cancel7.", &semfilename); + else + semfd = open (semfile, O_RDWR); + TEST_VERIFY_EXIT (semfd != -1); + + sem = xmmap (NULL, sizeof (sem_t), PROT_READ | PROT_WRITE, MAP_SHARED, + semfd); + TEST_VERIFY_EXIT (sem != SEM_FAILED); + if (semfile == NULL) + { + xftruncate (semfd, sizeof (sem_t)); + TEST_VERIFY_EXIT (sem_init (sem, 1, 0) != -1); + } + if (command == NULL) command = argv[0]; if (pidfile) sl (); - int fd = mkstemp (pidfilename); + int fd = create_temp_file ("tst-cancel7-pid-", &pidfilename); if (fd == -1) - { - puts ("mkstemp failed"); - exit (1); - } + FAIL_EXIT1 ("create_temp_file failed: %m"); - write (fd, " ", 1); - close (fd); + xwrite (fd, " ", 1); + xclose (fd); } static int do_test (void) { - pthread_t th; - if (pthread_create (&th, NULL, tf, NULL) != 0) - { - puts ("pthread_create failed"); - return 1; - } + pthread_t th = xpthread_create (NULL, tf, NULL); do - sleep (1); + nanosleep (&(struct timespec) { .tv_sec = 0, .tv_nsec = 100000000 }, NULL); while (access (pidfilename, R_OK) != 0); xpthread_cancel (th); void *r = xpthread_join (th); - sleep (1); + if (sem_wait (sem) != 0) + FAIL_EXIT1 ("sem_wait: %m"); - FILE *f = fopen (pidfilename, "r+"); - if (f == NULL) - { - puts ("no pidfile"); - return 1; - } + FILE *f = xfopen (pidfilename, "r+"); long long ll; if (fscanf (f, "%lld\n", &ll) != 1) - { - puts ("could not read pid"); - unlink (pidfilename); - return 1; - } + FAIL_EXIT1 ("fscanf: %m"); struct flock fl = { @@ -136,11 +140,7 @@ do_test (void) .l_len = 1 }; if (fcntl (fileno (f), F_GETLK, &fl) != 0) - { - puts ("F_GETLK failed"); - unlink (pidfilename); - return 1; - } + FAIL_EXIT1 ("fcntl: %m"); if (fl.l_type != F_UNLCK) { @@ -148,13 +148,10 @@ do_test (void) if (fl.l_pid == ll) kill (fl.l_pid, SIGKILL); - unlink (pidfilename); return 1; } - fclose (f); - - unlink (pidfilename); + xfclose (f); return r != PTHREAD_CANCELED; } @@ -180,15 +177,15 @@ do_cleanup (void) fclose (f); } - - unlink (pidfilename); } #define OPT_COMMAND 10000 #define OPT_PIDFILE 10001 +#define OPT_SEMFILE 10002 #define CMDLINE_OPTIONS \ { "command", required_argument, NULL, OPT_COMMAND }, \ - { "pidfile", required_argument, NULL, OPT_PIDFILE }, + { "pidfile", required_argument, NULL, OPT_PIDFILE }, \ + { "sem", required_argument, NULL, OPT_SEMFILE }, static void cmdline_process (int c) { @@ -200,6 +197,9 @@ cmdline_process (int c) case OPT_PIDFILE: pidfile = optarg; break; + case OPT_SEMFILE: + semfile = optarg; + break; } } #define CMDLINE_PROCESS cmdline_process