From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 27161 invoked by alias); 21 Jul 2004 17:39:23 -0000 Mailing-List: contact libc-hacker-help@sources.redhat.com; run by ezmlm Precedence: bulk List-Subscribe: List-Archive: List-Post: List-Help: , Sender: libc-hacker-owner@sources.redhat.com Received: (qmail 27141 invoked from network); 21 Jul 2004 17:39:23 -0000 Received: from unknown (HELO sunsite.ms.mff.cuni.cz) (195.113.15.26) by sourceware.org with SMTP; 21 Jul 2004 17:39:23 -0000 Received: from sunsite.ms.mff.cuni.cz (sunsite.mff.cuni.cz [127.0.0.1]) by sunsite.ms.mff.cuni.cz (8.12.8/8.12.8) with ESMTP id i6LFNO3j031213; Wed, 21 Jul 2004 17:23:24 +0200 Received: (from jakub@localhost) by sunsite.ms.mff.cuni.cz (8.12.8/8.12.8/Submit) id i6LFNOnL031211; Wed, 21 Jul 2004 17:23:24 +0200 Date: Wed, 21 Jul 2004 17:39:00 -0000 From: Jakub Jelinek To: Ulrich Drepper Cc: Glibc hackers Subject: [PATCH] Avoid leaks in res_init Message-ID: <20040721152324.GQ30497@sunsite.ms.mff.cuni.cz> Reply-To: Jakub Jelinek Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline User-Agent: Mutt/1.4.1i X-SW-Source: 2004-07/txt/msg00043.txt.bz2 Hi! #include #include #include int main (void) { int i; mtrace (); for (i = 0; i < 50; ++i) { res_init (); gethostbyname ("www.google.com"); } } leaks memory and if IPv6 is enabled also filehandles. I have googled around but could not find a word about whether res_init can or can't be called multiple times, but certainly we need such an interface e.g. for nscd to reread resolv.conf during nscd -i hosts. 2004-07-21 Jakub Jelinek * resolv/res_libc.c (res_init): If RES_INIT is set and _res.nscount > 0, call __res_nclose and free nsaddrs. --- libc/resolv/res_libc.c.jj 2003-07-23 09:56:18.000000000 +0200 +++ libc/resolv/res_libc.c 2004-07-21 19:25:05.419402346 +0200 @@ -54,6 +54,14 @@ res_init(void) { _res.retry = 4; if (!(_res.options & RES_INIT)) _res.options = RES_DEFAULT; + else if (_res.nscount > 0) { + __res_nclose (&_res); /* Close any VC sockets. */ + + for (int ns = 0; ns < MAXNS; ns++) { + free (_res._u._ext.nsaddrs[ns]); + _res._u._ext.nsaddrs[ns] = NULL; + } + } /* * This one used to initialize implicitly to zero, so unless the app Jakub