Received: from malur.postgresql.org ([217.196.149.56]) by arkaria.postgresql.org with esmtp (Exim 4.80) (envelope-from ) id 1VF5vI-00004r-97 for pgsql-hackers@arkaria.postgresql.org; Thu, 29 Aug 2013 17:22:20 +0000 Received: from localhost ([127.0.0.1] helo=postgresql.org) by malur.postgresql.org with smtp (Exim 4.80) (envelope-from ) id 1VF5vH-0000M9-PZ for pgsql-hackers@arkaria.postgresql.org; Thu, 29 Aug 2013 17:22:19 +0000 Received: from magus.postgresql.org ([2a02:c0:301:0:ffff::29]) by malur.postgresql.org with esmtp (Exim 4.80) (envelope-from ) id 1VF5vG-0000Lv-79 for pgsql-hackers@postgresql.org; Thu, 29 Aug 2013 17:22:18 +0000 Received: from smtp.01.com ([199.36.142.181] helo=smtp-out-2.01.com) by magus.postgresql.org with esmtp (Exim 4.80) (envelope-from ) id 1VF5vC-0000Km-VI for pgsql-hackers@postgresql.org; Thu, 29 Aug 2013 17:22:17 +0000 Received: from localhost (localhost [127.0.0.1]) by smtp-out-2.01.com (Postfix) with ESMTP id CC5F4390130; Thu, 29 Aug 2013 12:22:13 -0500 (CDT) X-Virus-Scanned: amavisd-new at smtp-out-2.01.com Received: from smtp-out-2.01.com ([127.0.0.1]) by localhost (smtp-out-2.01.com [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id YT8beDYHsDIK; Thu, 29 Aug 2013 12:22:13 -0500 (CDT) Received: from smtp-out-2.01.com (localhost [127.0.0.1]) by smtp-out-2.01.com (Postfix) with ESMTP id A3F9F39005D; Thu, 29 Aug 2013 12:22:13 -0500 (CDT) Received: from localhost (localhost [127.0.0.1]) by smtp-out-2.01.com (Postfix) with ESMTP id 8D77F39018B; Thu, 29 Aug 2013 12:22:13 -0500 (CDT) X-Virus-Scanned: amavisd-new at smtp-out-2.01.com Received: from smtp-out-2.01.com ([127.0.0.1]) by localhost (smtp-out-2.01.com [127.0.0.1]) (amavisd-new, port 10026) with ESMTP id YS_sgN8ifycb; Thu, 29 Aug 2013 12:22:13 -0500 (CDT) Received: from [172.47.23.103] (70-36-143-10.dsl.dynamic.sonic.net [70.36.143.10]) by smtp-out-2.01.com (Postfix) with ESMTPSA id 6E267390130; Thu, 29 Aug 2013 12:22:11 -0500 (CDT) Message-ID: <521F8340.6050408@agliodbs.com> Date: Thu, 29 Aug 2013 10:22:08 -0700 From: Josh Berkus Organization: PostgreSQL Experts Inc. User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:17.0) Gecko/20130803 Thunderbird/17.0.8 MIME-Version: 1.0 To: Tom Lane CC: Kohei KaiGai , "ktm@rice.edu" , Alexander Korotkov , Oleg Bartunov , Greg Smith , PgHacker Subject: Re: [v9.4] row level security References: <51E8A8C1.2050700@2ndQuadrant.com> <20130719030347.GV15510@tamriel.snowman.net> <51E8ADD9.5020600@2ndQuadrant.com> <521D1C2B.8090503@2ndQuadrant.com> <20130829142321.GA30496@aart.rice.edu> <521F7DFB.8060602@agliodbs.com> <9407.1377796701@sss.pgh.pa.us> In-Reply-To: X-Enigmail-Version: 1.5.2 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit X-Pg-Spam-Score: -1.9 (-) List-Archive: List-Help: List-ID: List-Owner: List-Post: List-Subscribe: List-Unsubscribe: X-Mailing-List: pgsql-hackers Precedence: bulk Sender: pgsql-hackers-owner@postgresql.org >> I'm not sure what the solution would be, exactly. Deny permission for >> EXPLAIN on certain tables? > > That would close only one covert channel. Others were already pointed out > upthread, and I'll bet there are more ... Mind you, fundamentally this is no different from allowing INSERT permission on a table but denying SELECT, or denying SELECT on certain columns. In either case, covert channels for some data are available. -- Josh Berkus PostgreSQL Experts Inc. http://pgexperts.com -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers