From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-lf1-x12d.google.com (mail-lf1-x12d.google.com [IPv6:2a00:1450:4864:20::12d]) by sourceware.org (Postfix) with ESMTPS id 755EB3945C06 for ; Tue, 13 Apr 2021 19:57:28 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.3.2 sourceware.org 755EB3945C06 Authentication-Results: sourceware.org; dmarc=none (p=none dis=none) header.from=mina86.com Authentication-Results: sourceware.org; spf=pass smtp.mailfrom=mnazarewicz@gmail.com Received: by mail-lf1-x12d.google.com with SMTP id j18so29317047lfg.5 for ; Tue, 13 Apr 2021 12:57:28 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=sender:from:to:cc:subject:in-reply-to:references:face:date :message-id:mime-version:content-transfer-encoding; bh=VsbvHjrZMPGDbwfRJzspGgGzwvJdi8yhi8SLGAMZsYw=; b=kwl0J3+h6fFh8flRQxOFNhNJUhcdKmXgC89SOsWJxHgYp8lbWtRzVF9ssBVGrCcrib hoBLEbwcTChLCkoVp11ZwbSp5L0fkA+MviCc8vy4hznovk6QseArRWL9HiPm9ZrTiaxe By8Yn4NeVMh27VjVbCyo+Q5o7JzJkkQTMcK1lslxOC96dfstmizKY0ltoULspWvYMCdi f+5z9y0POiIi7sD9iZ6QrZAkpmwHVBT+7P50x2DdoElGWtt+KlhvZFKAaJJIfhz4RQ/Y T5NuCyUOpDuceXwYZrnLLgDOYtE16UyD0N7/sORlgYCt/VRmDKFC1u6ZPyEymyEr4VH2 l3ng== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:sender:from:to:cc:subject:in-reply-to:references :face:date:message-id:mime-version:content-transfer-encoding; bh=VsbvHjrZMPGDbwfRJzspGgGzwvJdi8yhi8SLGAMZsYw=; b=BQEj+HlYsO/DvlV6xLpdDtjc9rRkL9oyAplsAsDFACuZsHiiPgEH6fhLQjnXk3GVYq UHRcwB6EJ0vuYhzrApvgrCRAx+qnfVH8cyDA4v0QyHA3UfToBOu9T3ooBQrDP9JIUOeT 0+o29XQ6oCWBn9O/6QIGJ7Osba0NKwBlKjyEaKsBB2QZu21yCeCEpzIBpcWvqVtAwAx5 YGdMzTSv34cs5aZ8/7gB/4Oe+4uutXZXVSQcWZxj+lpuVLpmFnvHF9oabDg1ND1t02my vBW3xJHchHeIJKBb6O9g1fjKMftL3pQff81FGp6E481w9LS7+DGhvbEC3hd0XLs992dy +B7g== X-Gm-Message-State: AOAM533Nrb50ElwW6g8TwC1tRFTnd/00ueld9bRG4X6ctW6oLNKTbcsX maOJEJIyNoSG/q0XGv0tGyZIsS/TnMa2qA== X-Google-Smtp-Source: ABdhPJxE7rAxFr+qfv3tHrt+uqbTnlxeOz3BRjT2WRWmvz7r6XFp1U+klHgyHViP+IvBNGhdrCJQQA== X-Received: by 2002:ac2:5613:: with SMTP id v19mr20250590lfd.492.1618343846840; Tue, 13 Apr 2021 12:57:26 -0700 (PDT) Received: from erwin (213-238-124-172.adsl.inetia.pl. [213.238.124.172]) by smtp.gmail.com with ESMTPSA id c27sm3628937lfv.149.2021.04.13.12.57.25 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 13 Apr 2021 12:57:26 -0700 (PDT) Sender: =?UTF-8?Q?Micha=C5=82_Nazarewicz?= From: Michal Nazarewicz To: Adhemerval Zanella , Andreas Schwab Cc: libc-alpha@sourceware.org Subject: Re: [PATCH] linux: sysconf: limit _SC_MAX_ARG to 6 MiB [BZ #25305] In-Reply-To: References: <20210407151058.1176364-1-mina86@mina86.com> <46c3ea60-7a57-14f7-92f9-e915e3b12dae@linaro.org> <87im4qe61s.fsf@igel.home> Face: 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 Date: Tue, 13 Apr 2021 21:57:25 +0200 Message-ID: <05wsjeil807oxrv57bk8g2i3@mina86.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable X-Spam-Status: No, score=-5.3 required=5.0 tests=BAYES_00, BODY_8BITS, DKIM_SIGNED, DKIM_VALID, DKIM_VALID_EF, FREEMAIL_FORGED_FROMDOMAIN, FREEMAIL_FROM, GIT_PATCH_0, HEADER_FROM_DIFFERENT_DOMAINS, MSGID_RANDY, RCVD_IN_BARRACUDACENTRAL, RCVD_IN_DNSWL_NONE, SPF_HELO_NONE, SPF_PASS, TXREP autolearn=ham autolearn_force=no version=3.4.2 X-Spam-Checker-Version: SpamAssassin 3.4.2 (2018-09-13) 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-List-Received-Date: Tue, 13 Apr 2021 19:57:30 -0000 > On 13/04/2021 09:13, Andreas Schwab wrote: >> In addition, I'd give it a symbolic name with a comment. On Tue, Apr 13 2021, Adhemerval Zanella wrote: > What about: > > diff --git a/sysdeps/unix/sysv/linux/sysconf.c b/sysdeps/unix/sysv/linux/= sysconf.c > index 366fcef01e..aceedfa87c 100644 > --- a/sysdeps/unix/sysv/linux/sysconf.c > +++ b/sysdeps/unix/sysv/linux/sysconf.c > @@ -33,6 +33,9 @@ > actual value varies based on the stack size. */ > #define legacy_ARG_MAX 131072 >=20=20 > +/* Newer kernels (4.13) limit the maximum command line arguments lengths= to > + 6MiB. */ > +#define maximum_ARG_MAX 6291456 I=E2=80=99d still go with (6 * 1024 * 1024). Otherwise looks good to me. > static long int posix_sysconf (int name); >=20=20 > @@ -55,7 +58,10 @@ __sysconf (int name) > struct rlimit rlimit; > /* Use getrlimit to get the stack limit. */ > if (__getrlimit (RLIMIT_STACK, &rlimit) =3D=3D 0) > - return MAX (legacy_ARG_MAX, rlimit.rlim_cur / 4); > + { > + const long int limit =3D MAX (legacy_ARG_MAX, rlimit.rlim_cur= / 4); > + return MIN (limit, maximum_ARG_MAX); > + } >=20=20 > return legacy_ARG_MAX; > } On Tue, Apr 13 2021, Adhemerval Zanella wrote: > Alright, I will change it and commit for you. Thanks. --=20 Best regards =E3=83=9F=E3=83=8F=E3=82=A6 =E2=80=9C=F0=9D=93=B6=F0=9D=93=B2=F0=9D=93=B7= =F0=9D=93=AA86=E2=80=9D =E3=83=8A=E3=82=B6=E3=83=AC=E3=83=B4=E3=82=A4=E3=83= =84 =C2=ABIf at first you don=E2=80=99t succeed, give up skydiving=C2=BB