From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.2 (2018-09-13) on dcvr.yhbt.net X-Spam-Level: X-Spam-Status: No, score=-3.8 required=3.0 tests=AWL,BAYES_00,DKIM_INVALID, DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, NICE_REPLY_A,RCVD_IN_MSPIKE_H4,RCVD_IN_MSPIKE_WL,SPF_HELO_PASS, SPF_PASS shortcircuit=no autolearn=unavailable autolearn_force=no version=3.4.2 Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dcvr.yhbt.net (Postfix) with ESMTPS id 613851F4B4 for ; Wed, 20 Jan 2021 14:14:51 +0000 (UTC) Received: from localhost ([::1]:38606 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1l2EG0-00047N-Cr for normalperson@yhbt.net; Wed, 20 Jan 2021 09:14:48 -0500 Received: from eggs.gnu.org ([2001:470:142:3::10]:53742) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1l2EEs-0003O0-QU for bug-gnulib@gnu.org; Wed, 20 Jan 2021 09:13:38 -0500 Received: from mail-qk1-x72c.google.com ([2607:f8b0:4864:20::72c]:39434) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_128_GCM_SHA256:128) (Exim 4.90_1) (envelope-from ) id 1l2EEq-0001nI-Eb for bug-gnulib@gnu.org; Wed, 20 Jan 2021 09:13:38 -0500 Received: by mail-qk1-x72c.google.com with SMTP id k193so4277636qke.6 for ; Wed, 20 Jan 2021 06:13:35 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; h=to:cc:references:from:autocrypt:subject:message-id:date:user-agent :mime-version:in-reply-to:content-language:content-transfer-encoding; bh=XlvUgh7qzhsa6iNrv2UNwfpBYHjXIxJW9JviDgDU4b8=; b=r9AftfHPZoA8YMJFkcuBL302CEbbhDgtwFoWDyM0bwbDWZqFL+etV2q4h3wfkXwJug LWqLvnT88fNeslFGpEo4TzbyzZhDTQQAJIorH8Mtkl3C8/l2QZQ+n/hw7zxGFdqI1kF5 tS3MDlysis2Z+tt6TW9P2CJRoSVnJ9hIA/kxUKuGM2V2/2FKy6Eao1UxK92DVUM32LbO tnN4e7A4gZOtEZu+c8L3hgancFYD6NkJfh1NF+AG++vf7Qoc548LF3An7yzv9kiIWEAc jmp09PeP38vPtIovjaKoNYSKvMzNQfJiyZ4SzC1v80dTyIfu7ALDwTgIEZAX9wVeMgJC GiqA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:to:cc:references:from:autocrypt:subject :message-id:date:user-agent:mime-version:in-reply-to :content-language:content-transfer-encoding; bh=XlvUgh7qzhsa6iNrv2UNwfpBYHjXIxJW9JviDgDU4b8=; b=l9xhOaAyfczptp2yIOa17IYNIsYWMzLfJsjEAd/hPk7jN6Pc2HHmFB6VTirDWBG+Pu lZTP3207zQlDgkUcO9EPYXbIsooSwiCJ0E7vIKc5NWu/LtNtg1u5gYt85H01bLOlE5U6 aCaiShq/8X+Tsflhm+15QPc8pEck8E5+/RdBiTcsJ/wezXIZGKhA2/bL7h6ClR3PKRmF M2IkHYH0/xQkX6YSkVEIsB+6xq9O2KgklbsaOQE1YJFL2Z1epbtWc7mKIRa7FUekPjP7 YOpyCO4UjCg0Uglb+AQa1cuJebZhfzWBTRo1hhZShXxUNQNvJq52fsvvd1AJTMEETbJY R3Ug== X-Gm-Message-State: AOAM532vA+u/6hVEFRDKG59A7ECLquhclcZhm+AUeMfObXsuWjG1PUe7 b9jGhoS7TZrRhyqxfU31J2wJ+5FqpAI+3g== X-Google-Smtp-Source: ABdhPJzL4PKGwQPG1wBV5rYROYpjoqvmdgeha9jZ2WPouzockLz5+6XB/ii4TQ+eydruMbgk4sNtEQ== X-Received: by 2002:a37:a86:: with SMTP id 128mr9240870qkk.147.1611152014250; Wed, 20 Jan 2021 06:13:34 -0800 (PST) Received: from [192.168.1.4] ([177.194.48.209]) by smtp.googlemail.com with ESMTPSA id d3sm1423321qka.36.2021.01.20.06.13.32 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Wed, 20 Jan 2021 06:13:33 -0800 (PST) To: DJ Delorie References: From: Adhemerval Zanella Autocrypt: addr=adhemerval.zanella@linaro.org; prefer-encrypt=mutual; keydata= mQINBFcVGkoBEADiQU2x/cBBmAVf5C2d1xgz6zCnlCefbqaflUBw4hB/bEME40QsrVzWZ5Nq 8kxkEczZzAOKkkvv4pRVLlLn/zDtFXhlcvQRJ3yFMGqzBjofucOrmdYkOGo0uCaoJKPT186L NWp53SACXguFJpnw4ODI64ziInzXQs/rUJqrFoVIlrPDmNv/LUv1OVPKz20ETjgfpg8MNwG6 iMizMefCl+RbtXbIEZ3TE/IaDT/jcOirjv96lBKrc/pAL0h/O71Kwbbp43fimW80GhjiaN2y WGByepnkAVP7FyNarhdDpJhoDmUk9yfwNuIuESaCQtfd3vgKKuo6grcKZ8bHy7IXX1XJj2X/ BgRVhVgMHAnDPFIkXtP+SiarkUaLjGzCz7XkUn4XAGDskBNfbizFqYUQCaL2FdbW3DeZqNIa nSzKAZK7Dm9+0VVSRZXP89w71Y7JUV56xL/PlOE+YKKFdEw+gQjQi0e+DZILAtFjJLoCrkEX w4LluMhYX/X8XP6/C3xW0yOZhvHYyn72sV4yJ1uyc/qz3OY32CRy+bwPzAMAkhdwcORA3JPb kPTlimhQqVgvca8m+MQ/JFZ6D+K7QPyvEv7bQ7M+IzFmTkOCwCJ3xqOD6GjX3aphk8Sr0dq3 4Awlf5xFDAG8dn8Uuutb7naGBd/fEv6t8dfkNyzj6yvc4jpVxwARAQABtElBZGhlbWVydmFs IFphbmVsbGEgTmV0dG8gKExpbmFybyBWUE4gS2V5KSA8YWRoZW1lcnZhbC56YW5lbGxhQGxp bmFyby5vcmc+iQI3BBMBCAAhBQJXFRpKAhsDBQsJCAcDBRUKCQgLBRYCAwEAAh4BAheAAAoJ EKqx7BSnlIjv0e8P/1YOYoNkvJ+AJcNUaM5a2SA9oAKjSJ/M/EN4Id5Ow41ZJS4lUA0apSXW NjQg3VeVc2RiHab2LIB4MxdJhaWTuzfLkYnBeoy4u6njYcaoSwf3g9dSsvsl3mhtuzm6aXFH /Qsauav77enJh99tI4T+58rp0EuLhDsQbnBic/ukYNv7sQV8dy9KxA54yLnYUFqH6pfH8Lly sTVAMyi5Fg5O5/hVV+Z0Kpr+ZocC1YFJkTsNLAW5EIYSP9ftniqaVsim7MNmodv/zqK0IyDB GLLH1kjhvb5+6ySGlWbMTomt/or/uvMgulz0bRS+LUyOmlfXDdT+t38VPKBBVwFMarNuREU2 69M3a3jdTfScboDd2ck1u7l+QbaGoHZQ8ZNUrzgObltjohiIsazqkgYDQzXIMrD9H19E+8fw kCNUlXxjEgH/Kg8DlpoYJXSJCX0fjMWfXywL6ZXc2xyG/hbl5hvsLNmqDpLpc1CfKcA0BkK+ k8R57fr91mTCppSwwKJYO9T+8J+o4ho/CJnK/jBy1pWKMYJPvvrpdBCWq3MfzVpXYdahRKHI ypk8m4QlRlbOXWJ3TDd/SKNfSSrWgwRSg7XCjSlR7PNzNFXTULLB34sZhjrN6Q8NQZsZnMNs TX8nlGOVrKolnQPjKCLwCyu8PhllU8OwbSMKskcD1PSkG6h3r0AquQINBFcVGkoBEACgAdbR Ck+fsfOVwT8zowMiL3l9a2DP3Eeak23ifdZG+8Avb/SImpv0UMSbRfnw/N81IWwlbjkjbGTu oT37iZHLRwYUFmA8fZX0wNDNKQUUTjN6XalJmvhdz9l71H3WnE0wneEM5ahu5V1L1utUWTyh VUwzX1lwJeV3vyrNgI1kYOaeuNVvq7npNR6t6XxEpqPsNc6O77I12XELic2+36YibyqlTJIQ V1SZEbIy26AbC2zH9WqaKyGyQnr/IPbTJ2Lv0dM3RaXoVf+CeK7gB2B+w1hZummD21c1Laua +VIMPCUQ+EM8W9EtX+0iJXxI+wsztLT6vltQcm+5Q7tY+HFUucizJkAOAz98YFucwKefbkTp eKvCfCwiM1bGatZEFFKIlvJ2QNMQNiUrqJBlW9nZp/k7pbG3oStOjvawD9ZbP9e0fnlWJIsj 6c7pX354Yi7kxIk/6gREidHLLqEb/otuwt1aoMPg97iUgDV5mlNef77lWE8vxmlY0FBWIXuZ yv0XYxf1WF6dRizwFFbxvUZzIJp3spAao7jLsQj1DbD2s5+S1BW09A0mI/1DjB6EhNN+4bDB SJCOv/ReK3tFJXuj/HbyDrOdoMt8aIFbe7YFLEExHpSk+HgN05Lg5TyTro8oW7TSMTk+8a5M kzaH4UGXTTBDP/g5cfL3RFPl79ubXwARAQABiQIfBBgBCAAJBQJXFRpKAhsMAAoJEKqx7BSn lIjvI/8P/jg0jl4Tbvg3B5kT6PxJOXHYu9OoyaHLcay6Cd+ZrOd1VQQCbOcgLFbf4Yr+rE9l mYsY67AUgq2QKmVVbn9pjvGsEaz8UmfDnz5epUhDxC6yRRvY4hreMXZhPZ1pbMa6A0a/WOSt AgFj5V6Z4dXGTM/lNManr0HjXxbUYv2WfbNt3/07Db9T+GZkpUotC6iknsTA4rJi6u2ls0W9 1UIvW4o01vb4nZRCj4rni0g6eWoQCGoVDk/xFfy7ZliR5B+3Z3EWRJcQskip/QAHjbLa3pml xAZ484fVxgeESOoaeC9TiBIp0NfH8akWOI0HpBCiBD5xaCTvR7ujUWMvhsX2n881r/hNlR9g fcE6q00qHSPAEgGr1bnFv74/1vbKtjeXLCcRKk3Ulw0bY1OoDxWQr86T2fZGJ/HIZuVVBf3+ gaYJF92GXFynHnea14nFFuFgOni0Mi1zDxYH/8yGGBXvo14KWd8JOW0NJPaCDFJkdS5hu0VY 7vJwKcyHJGxsCLU+Et0mryX8qZwqibJIzu7kUJQdQDljbRPDFd/xmGUFCQiQAncSilYOcxNU EMVCXPAQTteqkvA+gNqSaK1NM9tY0eQ4iJpo+aoX8HAcn4sZzt2pfUB9vQMTBJ2d4+m/qO6+ cFTAceXmIoFsN8+gFN3i8Is3u12u8xGudcBPvpoy4OoG Subject: Re: [PATCH v3 6/6] stdlib: Add testcase fro BZ #26241 Message-ID: <19343d42-febd-6f8c-6242-bb36a5eb527d@linaro.org> Date: Wed, 20 Jan 2021 11:13:30 -0300 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.10.0 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 8bit Received-SPF: pass client-ip=2607:f8b0:4864:20::72c; envelope-from=adhemerval.zanella@linaro.org; helo=mail-qk1-x72c.google.com X-Spam_score_int: -21 X-Spam_score: -2.2 X-Spam_bar: -- X-Spam_report: (-2.2 / 5.0 requ) BAYES_00=-1.9, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, NICE_REPLY_A=-0.094, RCVD_IN_DNSWL_NONE=-0.0001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: bug-gnulib@gnu.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: Gnulib discussion list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: bug-gnulib@gnu.org, eggert@cs.ucla.edu, libc-alpha@sourceware.org Errors-To: bug-gnulib-bounces+normalperson=yhbt.net@gnu.org Sender: "bug-gnulib" On 20/01/2021 01:33, DJ Delorie wrote: > > Adhemerval Zanella via Libc-alpha writes: >> - tst-setcontext9 tst-bz20544 >> + tst-setcontext9 tst-bz20544 tst-canon-bz26341 > > New test, ok. > >> +LDLIBS-tst-canon-bz26341 = $(shared-thread-library) > > Ok. > >> diff --git a/stdlib/tst-canon-bz26341.c b/stdlib/tst-canon-bz26341.c > >> +/* Check if realpath does not consume extra stack space based on symlink >> + existance in the path (BZ #26341) > > Is this allowed to be two lines? Good question. GNU code guidelines does not really restrict a number of line, it is just says Also, please write a brief comment at the start of each source file, with the file name and a line or two about the overall purpose of the file. We do have other file with two line comments, so I think it should be fine. > >> + Copyright (C) 2020 Free Software Foundation, Inc. > > Year is wrong now :-) Ack. > >> +#include >> +#include >> +#include >> +#include > > Ok > >> +#define __sysconf sysconf >> +#include >> +#include >> +#include >> +#include >> +#include >> +#include > > Ok > >> +static char *filename; >> +static size_t filenamelen; >> +static char *linkname; >> + >> +#ifndef PATH_MAX >> +# define PATH_MAX 1024 >> +#endif > > Ok. > >> +static void >> +create_link (void) >> +{ >> + int fd = create_temp_file ("tst-canon-bz26341", &filename); >> + TEST_VERIFY_EXIT (fd != -1); >> + xclose (fd); >> + >> + char *prevlink = filename; >> + int maxlinks = __eloop_threshold (); >> + for (int i = 0; i < maxlinks; i++) >> + { >> + linkname = xasprintf ("%s%d", filename, i); >> + xsymlink (prevlink, linkname); > > linkname -> prevlink -> filename > >> + add_temp_file (linkname); >> + prevlink = linkname; >> + } >> + >> + filenamelen = strlen (filename); >> +} > > On exit, linkname has the last link created. Needs a comment to that > effect. I added prior the link creations. /* Create MAXLINKS symbolic links to the temporary filename. On exit, linkname has the last link created. */ > > >> +static void * >> +do_realpath (void *arg) >> +{ >> + /* Old implementation of realpath allocates a PATH_MAX using alloca >> + for each symlink in the path, leading to MAXSYMLINKS times PATH_MAX >> + maximum stack usage. >> + This stack allocations tries fill the thread allocated stack minus >> + both the resolved path (plus some slack) and the realpath (plus some >> + slack). >> + If realpath uses more than 2 * PATH_MAX plus some slack it will trigger >> + a stackoverflow. */ >> + >> + const size_t realpath_usage = 2 * PATH_MAX + 1024; >> + const size_t thread_usage = 1 * PATH_MAX + 1024; >> + size_t stack_size = support_small_thread_stack_size () >> + - realpath_usage - thread_usage; >> + char stack[stack_size]; >> + char *resolved = stack + stack_size - thread_usage + 1024; > > This points us at PATH_MAX away from the end of stack[]. Ok. Also > forces most of the stack to get used up :-) > >> + char *p = realpath (linkname, resolved); > > We assume the test will crash if we use more stack than we allocated. > >> + TEST_VERIFY (p != NULL); > > realpath() must succeed, ok > >> + TEST_COMPARE_BLOB (resolved, filenamelen, filename, filenamelen); > > And give us the right result, ok > >> + return NULL; >> +} >> + >> +static int >> +do_test (void) >> +{ >> + create_link (); >> + >> + pthread_t th = xpthread_create (support_small_stack_thread_attribute (), >> + do_realpath, NULL); >> + xpthread_join (th); >> + >> + return 0; >> +} > > Run the test in a thread with a small stack, ok. > >> +#include > > LGTM with that comment. > > Reviewed-by: DJ Delorie > [1] https://www.gnu.org/prep/standards/html_node/Comments.html