From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-il1-x141.google.com (mail-il1-x141.google.com [IPv6:2607:f8b0:4864:20::141]) by sourceware.org (Postfix) with ESMTPS id B253B3894E5A for ; Wed, 29 Apr 2020 20:30:17 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.3.2 sourceware.org B253B3894E5A Received: by mail-il1-x141.google.com with SMTP id x2so3737085ilp.13 for ; Wed, 29 Apr 2020 13:30:17 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=lAIIsvPZxW/G5rXAwgcO/QgxpguHxB2/QQwZJRvfLJ4=; b=lifDY6V9FRezuqpq9RTlFJG/kOQbUgXAZCazxxoGoe/AAy0h5i3MUG+S2rlPRrgODz ZLoifAC/cDwfl+o/MwlESACgvdk77w4JmiPTljNRaT/buDRuA3ricLPAI7t5kvmByCA7 ywAvg0kTiNjP/EkOPPVubm5aD7YofE8zJTiGC6BecUz70K90JBPBvaVl9SmmEHv4dFjb DKcLzF6I/QJMumEBKWLiS/9rNhHhgFmFLHEAfT1IiYKHlbpNtSahH8hTv68FMSVhisWe txqxSjz7C9xD1hxKd5W7Z2KIVQwLEFV1TdehQg4IAWNxdK0xzMxu5k71EIIffeNg3/mm Bdrw== X-Gm-Message-State: AGi0PuYbwzc8f0hFOC1HrFh5YMQ7PWJpw77chuUnxeFYIpxR2GE7kch9 70O9b+kcNu/h69vs4+A5IOKSxXs2SpSBEftzX9B7NfED X-Google-Smtp-Source: APiQypLQJ2hTaHgmiOelKMmyh/20GrW0ub/XxIfDk+CZCeOhLEnhpVkfDDv0m+awDUFp8BEtkjpdmAMa12nPHDP4rOw= X-Received: by 2002:a92:cc4a:: with SMTP id t10mr154718ilq.292.1588192217186; Wed, 29 Apr 2020 13:30:17 -0700 (PDT) MIME-Version: 1.0 References: <20200428215243.236312-1-hjl.tools@gmail.com> In-Reply-To: From: "H.J. Lu" Date: Wed, 29 Apr 2020 13:29:41 -0700 Message-ID: Subject: Re: [PATCH 0/3] x86: Add --enable-cet=permissive To: Adhemerval Zanella Cc: GNU C Library Content-Type: text/plain; charset="UTF-8" X-Spam-Status: No, score=-11.2 required=5.0 tests=BAYES_00, DKIM_SIGNED, DKIM_VALID, DKIM_VALID_AU, DKIM_VALID_EF, FREEMAIL_FROM, GIT_PATCH_2, GIT_PATCH_3, 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: Wed, 29 Apr 2020 20:30:20 -0000 On Wed, Apr 29, 2020 at 11:27 AM Adhemerval Zanella via Libc-alpha wrote: > > > > On 28/04/2020 18:52, H.J. Lu via Libc-alpha wrote: > > When CET is enabled, it is an error to dlopen a non CET enabled shared > > library in CET enabled application. It may be desirable to make CET > > permissive, that is disable CET when dlopening a non CET enabled shared > > library. With the new --enable-cet=permissive configure option, CET is > > disabled when dlopening a non CET enabled shared library. > > Does not CET already provide a tunable to make it permissive? If the idea Yes, it can be controlled by a tunable. > is to enable as de-facto for a distro bootstrap, why not make it default > then? A distro can choose CET control default to permissive or enforced at build time. > > > > To support --enable-cet=permissive, CET_MAX is renamed to > > CET_CONTROL_MASK and is included in rtld.c to get > > architecture specific initializer in rtld_global. > > > > H.J. Lu (3): > > CET: Rename CET_MAX to CET_CONTROL_MASK [BZ #25887] > > rtld: Get architecture specific initializer in rtld_global > > x86: Add --enable-cet=permissive > > > > INSTALL | 26 +++++++++++-------- > > config.h.in | 3 +++ > > elf/rtld.c | 2 ++ > > manual/install.texi | 12 ++++++--- > > sysdeps/unix/sysv/linux/x86/Makefile | 2 +- > > sysdeps/x86/Makefile | 18 +++++++++---- > > sysdeps/x86/cet-tunables.h | 22 ++++++++++++++-- > > sysdeps/x86/configure | 21 ++++++++------- > > sysdeps/x86/configure.ac | 19 +++++++------- > > sysdeps/x86/cpu-features.c | 7 +++-- > > sysdeps/x86/cpu-tunables.c | 39 +++++++++++----------------- > > sysdeps/x86/dl-cet.c | 6 ++--- > > sysdeps/x86/dl-procruntime.c | 5 ++++ > > sysdeps/x86/tst-cet-legacy-5.c | 25 ++++++++++++------ > > sysdeps/x86/tst-cet-legacy-6.c | 25 ++++++++++++------ > > 15 files changed, 141 insertions(+), 91 deletions(-) > > -- H.J.