From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.133.124]) by sourceware.org (Postfix) with ESMTPS id 8FDB63858413 for ; Tue, 21 Dec 2021 18:12:06 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.4.1 sourceware.org 8FDB63858413 Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-144-1v-cLeNBPle7Mfsuvwezfg-1; Tue, 21 Dec 2021 13:12:03 -0500 X-MC-Unique: 1v-cLeNBPle7Mfsuvwezfg-1 Received: from smtp.corp.redhat.com (int-mx08.intmail.prod.int.phx2.redhat.com [10.5.11.23]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 1EAF71932484; Tue, 21 Dec 2021 18:12:02 +0000 (UTC) Received: from oldenburg.str.redhat.com (unknown [10.39.192.104]) by smtp.corp.redhat.com (Postfix) with ESMTPS id D242C9329; Tue, 21 Dec 2021 18:11:55 +0000 (UTC) From: Florian Weimer To: Adhemerval Zanella Cc: libc-alpha@sourceware.org, John Mellor-Crummey , Ben Woodard Subject: Re: [PATCH v6 19/20] elf: Fix runtime linker auditing on aarch64 (BZ #26643) References: <20211115183734.531155-1-adhemerval.zanella@linaro.org> <20211115183734.531155-20-adhemerval.zanella@linaro.org> <87zgovc68b.fsf@oldenburg.str.redhat.com> <87mtku9fvd.fsf@oldenburg.str.redhat.com> <87ee669fey.fsf@oldenburg.str.redhat.com> <87r1a598l2.fsf@oldenburg.str.redhat.com> Date: Tue, 21 Dec 2021 19:11:54 +0100 In-Reply-To: (Adhemerval Zanella's message of "Tue, 21 Dec 2021 14:38:54 -0300") Message-ID: <87fsql96ad.fsf@oldenburg.str.redhat.com> User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/27.2 (gnu/linux) MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.84 on 10.5.11.23 X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Type: text/plain X-Spam-Status: No, score=-6.3 required=5.0 tests=BAYES_00, DKIMWL_WL_HIGH, DKIM_SIGNED, DKIM_VALID, DKIM_VALID_AU, DKIM_VALID_EF, RCVD_IN_DNSWL_LOW, RCVD_IN_MSPIKE_H3, RCVD_IN_MSPIKE_WL, SPF_HELO_NONE, SPF_NONE, 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-List-Received-Date: Tue, 21 Dec 2021 18:12:07 -0000 * Adhemerval Zanella: >> . *If* a user shows up whose aarch64 audit modules were broken by the >> fix for bug 26643, support two ABIs for the PLT enter/exit hooks. > > And that is what I really dislike and I want to avoid, I see absolute > no gain about supporting an interface for aarch64 (or any other port, > the issue is only aarch64 is currently showing) that has subtle and > broken API. I agree! I just want to have an escape hatch in case we have to support them. That's why I recommend changing LAV_CURRENT. > For aarch64 I still think it better to just avoid loading old audit > modules. In the end, it is your port, but I strongly advise against this. >> . Consider issuing more la_symbind callbacks for LAV_CURRENT == 2 >> only (BIND_NOW functions and basically all symbols). >> > What about newer audit module version that request PLT trace? Currently > my plan is to stop execution with an error, instead of just ignoring it. You mean la_version returns 2, a jump slot is available, and the la_symbind function requests callbacks? I don't see why we'd have to reject that. Thanks, Florian