Received: from malur.postgresql.org ([2a02:16a8:dc51::56]) by arkaria.postgresql.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_CBC_SHA384:256) (Exim 4.89) (envelope-from ) id 1fhppb-0003al-G2 for pgsql-hackers@arkaria.postgresql.org; Tue, 24 Jul 2018 05:25:55 +0000 Received: from localhost ([127.0.0.1] helo=malur.postgresql.org) by malur.postgresql.org with esmtp (Exim 4.89) (envelope-from ) id 1fhppZ-0003nI-Uy for pgsql-hackers@arkaria.postgresql.org; Tue, 24 Jul 2018 05:25:53 +0000 Received: from magus.postgresql.org ([2a02:c0:301:0:ffff::29]) by malur.postgresql.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_CBC_SHA384:256) (Exim 4.89) (envelope-from ) id 1fhppZ-0003n6-O3 for pgsql-hackers@lists.postgresql.org; Tue, 24 Jul 2018 05:25:53 +0000 Received: from wout5-smtp.messagingengine.com ([64.147.123.21]) by magus.postgresql.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_CBC_SHA384:256) (Exim 4.89) (envelope-from ) id 1fhppU-0001L7-Jh for pgsql-hackers@lists.postgresql.org; Tue, 24 Jul 2018 05:25:53 +0000 Received: from compute4.internal (compute4.nyi.internal [10.202.2.44]) by mailout.west.internal (Postfix) with ESMTP id 5A7D2320; Tue, 24 Jul 2018 01:25:46 -0400 (EDT) Received: from mailfrontend2 ([10.202.2.163]) by compute4.internal (MEProxy); Tue, 24 Jul 2018 01:25:46 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=paquier.xyz; h= cc:content-type:date:from:in-reply-to:message-id:mime-version :references:subject:to:x-me-sender:x-me-sender:x-sasl-enc; s= fm2; bh=LX47lyAVCo1yCT3mj2CKkgQr69XfsjE/njB5R6l+XCY=; b=wYcQ8N9i pLXkR9HPUxiVFVHNccjHSdWH6LCsb8lRBpF09mjeJkIg9qzG2qGyz8PYES3mFlMu qhFvXV+rLR6XoYmxqs839airdHj+dm/Y4I+P7IdZlZAwa2rHqwVlFGZUfA35KmFm hUhUWKkkqYvZAgggyHKegSyQ0qgrxfJEJndTpVuLDkWyawyTVLyExhdbIP0QSIke bsnRqJXalWv5rpJpNnxhrK6pPcJZ1g6ldsqzJzQIFigZQ3tvQMS3BbtDgpCO4JZ/ IDko+ou/Tnmg3/2blvfQCh8XimxPsSDndRCqBp8f73pvOXzgSY1kL1q3DVGuBWdJ mEMac6SREglWRg== DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d= messagingengine.com; h=cc:content-type:date:from:in-reply-to :message-id:mime-version:references:subject:to:x-me-sender :x-me-sender:x-sasl-enc; s=fm3; bh=LX47lyAVCo1yCT3mj2CKkgQr69Xfs jE/njB5R6l+XCY=; b=kYENNqOnAA/9UGwPz/B5xLEXjC3c9mXpgS/hmnu0PbWMv ZweHvJ4qlKyZRaQdcIAGl/fKDV+j8lNHQtFZGSNNEuw1d9bFq/gBu6RO2p/rA74v FQhQHEwlpMSi9i4E2Igicweki9kC945LDuREJsJ/dlzA/IB2ujYPNlPni0Tzo3/h UQ0bMLkOinS947+YudOayednhn242UmWUW9Cy1YKga5HJl2KJ5slyi5QjuJJ812w KkwvJxflmp8oyAty8+DQsuSz/gfWmUDS47kgK1s7EuIcgvXNXem+8j8k9R149i6u 23dJmfSoDaRjtHlzQxnm3GL9/1zZN3421mnbsBfVw== X-ME-Proxy: X-ME-Sender: Received: from paquier.xyz (c137162.net61215.cablenet.ne.jp [61.215.137.162]) by mail.messagingengine.com (Postfix) with ESMTPA id 8568E1025D; Tue, 24 Jul 2018 01:25:43 -0400 (EDT) Date: Tue, 24 Jul 2018 14:25:40 +0900 From: Michael Paquier To: Andres Freund Cc: pgsql-hackers@lists.postgresql.org, Robert Haas , Jeremy Schneider , PostgreSQL-development , "Albin, Lloyd P" Subject: Re: BUG #15182: Canceling authentication due to timeout aka Denial of Service Attack Message-ID: <20180724052540.GC4736@paquier.xyz> References: <152512087100.19803.12733865831237526317@wrigleys.postgresql.org> <9145334b-9583-124c-012e-7d58039ad417@amazon.com> <20180724041403.GF4035@paquier.xyz> <20180724045010.GA4736@paquier.xyz> <20180724052302.GB4736@paquier.xyz> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha512; protocol="application/pgp-signature"; boundary="yLVHuoLXiP9kZBkt" Content-Disposition: inline In-Reply-To: <20180724052302.GB4736@paquier.xyz> List-Id: List-Help: List-Subscribe: List-Post: List-Owner: List-Archive: Precedence: bulk --yLVHuoLXiP9kZBkt Content-Type: text/plain; charset=us-ascii Content-Disposition: inline On Tue, Jul 24, 2018 at 02:23:02PM +0900, Michael Paquier wrote: > Well, letting any users take an exclusive lock on system catalogs at > will is not acceptable either, so two possible answers would be to fail > or skip such relations. The first concept applies if a relation list is > given by the user, and the second if no list is given. The first sentence is incorrect. That's actually "letting any users attempt to take an exclusive lock which makes others to be stuck as well". -- Michael --yLVHuoLXiP9kZBkt Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iQIzBAABCgAdFiEEG72nH6vTowiyblFKnvQgOdbyQH0FAltWuFQACgkQnvQgOdby QH3TQQ//dDYYiAu0C07A3ejBJZURTE81FfnhlD3RBU1wGUwHs5lqJdMLjhVWpzp1 wU7gLR3NtWKYYxY/Ty3sOWye1A30uYVcyb9K9V4Ipebm/bKyws71G5yBj/7DCC+K Ws9cBs2x/P/aNWUVDHN51bJ2agJbE2YEGK9LJ66xrs6Oyqn215sIwF/E4Yn8e8/C ICohJL8JmAp6My34EBL6ztJsqMB8fKp6quMRftfEznUGSbzwnaR1OuAzA3S2zY4F 0S2ml0NZvWHZyA+IWETs2vOWWczUgYdQ8aNY4gvclnfkHhLGNUz13jRQMJ3w/3Ra vKzea5RMZqXiHDDFHxk7zMHmwNvguJ9xlDvrqbxCnfS/KiyZQx4Wf7LRFe88IZXU T7z2HnERqNlc5xC7tDL9pkcbUChKAwgDxY8o9L3eySHAZIwFBI+T4yzDlpNjCEyY uQA/pZW1Q1+gdVzdxeP8JQPKMkJr48VHuNU71wWKF1rHJLHNgcITn3WeXnDYhRK3 OvM0XN3cK1IdMnpecLw7PjNp8hJM5gNBgUCJ/f0ShDZdeHUK705pPxUGN9gAotMB FNY0/AetkEiRLer4dtjpXqhiNabjIs1di5YlorFvOS32k7XJt0rG03rdO2wr6IAH YqAZUAediW2SMed7DgHTYsyDI+SXTbI1z6U/tY7b6cQzCNLzG7k= =rLHj -----END PGP SIGNATURE----- --yLVHuoLXiP9kZBkt--