From owner-freebsd-hackers@freebsd.org Thu Nov 28 13:12:21 2019 Return-Path: Delivered-To: freebsd-hackers@mailman.nyi.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2610:1c1:1:606c::19:1]) by mailman.nyi.freebsd.org (Postfix) with ESMTP id EF15D1A9327 for ; Thu, 28 Nov 2019 13:12:21 +0000 (UTC) (envelope-from kostikbel@gmail.com) Received: from kib.kiev.ua (kib.kiev.ua [IPv6:2001:470:d5e7:1::1]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) server-signature RSA-PSS (4096 bits)) (Client did not present a certificate) by mx1.freebsd.org (Postfix) with ESMTPS id 47NyjK1m5Nz4YjS for ; Thu, 28 Nov 2019 13:12:21 +0000 (UTC) (envelope-from kostikbel@gmail.com) Received: from tom.home (kib@localhost [127.0.0.1]) by kib.kiev.ua (8.15.2/8.15.2) with ESMTPS id xASDCBFY012713 (version=TLSv1.3 cipher=TLS_AES_256_GCM_SHA384 bits=256 verify=NO); Thu, 28 Nov 2019 15:12:15 +0200 (EET) (envelope-from kostikbel@gmail.com) DKIM-Filter: OpenDKIM Filter v2.10.3 kib.kiev.ua xASDCBFY012713 Received: (from kostik@localhost) by tom.home (8.15.2/8.15.2/Submit) id xASDCBP4012712; Thu, 28 Nov 2019 15:12:11 +0200 (EET) (envelope-from kostikbel@gmail.com) X-Authentication-Warning: tom.home: kostik set sender to kostikbel@gmail.com using -f Date: Thu, 28 Nov 2019 15:12:11 +0200 From: Konstantin Belousov To: Peter Blok Cc: freebsd-hackers@freebsd.org Subject: Re: dynamic loadable library multiple degined symbols Message-ID: <20191128131211.GQ10580@kib.kiev.ua> References: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.12.2 (2019-09-21) X-Spam-Status: No, score=-1.0 required=5.0 tests=ALL_TRUSTED,BAYES_00, DKIM_ADSP_CUSTOM_MED,FORGED_GMAIL_RCVD,FREEMAIL_FROM, NML_ADSP_CUSTOM_MED autolearn=no autolearn_force=no version=3.4.2 X-Spam-Checker-Version: SpamAssassin 3.4.2 (2018-09-13) on tom.home X-Rspamd-Queue-Id: 47NyjK1m5Nz4YjS X-Spamd-Bar: - Authentication-Results: mx1.freebsd.org; dkim=none; dmarc=fail reason="No valid SPF, No valid DKIM" header.from=gmail.com (policy=none); spf=softfail (mx1.freebsd.org: 2001:470:d5e7:1::1 is neither permitted nor denied by domain of kostikbel@gmail.com) smtp.mailfrom=kostikbel@gmail.com X-Spamd-Result: default: False [-2.00 / 15.00]; ARC_NA(0.00)[]; NEURAL_HAM_MEDIUM(-1.00)[-1.000,0]; RCVD_TLS_ALL(0.00)[]; FROM_HAS_DN(0.00)[]; TO_DN_SOME(0.00)[]; FREEMAIL_FROM(0.00)[gmail.com]; NEURAL_HAM_LONG(-1.00)[-1.000,0]; MIME_GOOD(-0.10)[text/plain]; HAS_XAW(0.00)[]; R_SPF_SOFTFAIL(0.00)[~all:c]; IP_SCORE_FREEMAIL(0.00)[]; TO_MATCH_ENVRCPT_SOME(0.00)[]; RCPT_COUNT_TWO(0.00)[2]; IP_SCORE(0.00)[ip: (-2.77), ipnet: 2001:470::/32(-4.64), asn: 6939(-3.52), country: US(-0.05)]; FROM_EQ_ENVFROM(0.00)[]; R_DKIM_NA(0.00)[]; MIME_TRACE(0.00)[0:+]; ASN(0.00)[asn:6939, ipnet:2001:470::/32, country:US]; RCVD_COUNT_TWO(0.00)[2]; FREEMAIL_ENVFROM(0.00)[gmail.com]; DMARC_POLICY_SOFTFAIL(0.10)[gmail.com : No valid SPF, No valid DKIM,none] X-BeenThere: freebsd-hackers@freebsd.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Technical Discussions relating to FreeBSD List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Thu, 28 Nov 2019 13:12:22 -0000 On Thu, Nov 28, 2019 at 01:50:15PM +0100, Peter Blok wrote: > Hi, > > named (bind9.14) has a function called dns_name_equal. (0000000000443ac0 T dns_name_equal) > > named dynamically loads dlz_bind9_14.so is build from dlz_bind9.c and calls this function, but dns_name_equal was undefined so it got resolved to the version of named. > > The function is defined in dns_utils.c, so I changed the building to include that file. > > Now dlz_bind9_14.so is using dlz_bind9.c and dns_utils.c also has the right dns_name_equal (000000000000bee0 T dns_name_equal) defined > > Unfortunately the code inside dlz_bind9_14.so still calls the function out of named. > > Is this something that should have been resolved at compile/link time of dlz_bind9_14.so? If so, how? No, default ELF name resolution rules would give the behaviour you described, assuming the main binary was linked with -Wl,-E (and it must be to export symbols to loadable modules). The shared libraries and loadable modules are interposable by default, unless linked with -B symbolic, and the symbol resolution order starts from the main binary object. Why do you try to change this ? > > Note that the samba build uses waf and wscript files. > > Peter > >