From patchwork Tue Jun 3 23:36:42 2014 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Aurelien Jarno X-Patchwork-Id: 1277 Received: (qmail 23824 invoked by alias); 3 Jun 2014 23:59:42 -0000 Mailing-List: contact libc-alpha-help@sourceware.org; run by ezmlm Precedence: bulk List-Id: List-Unsubscribe: List-Subscribe: List-Archive: List-Post: List-Help: , Sender: libc-alpha-owner@sourceware.org Delivered-To: mailing list libc-alpha@sourceware.org Received: (qmail 23813 invoked by uid 89); 3 Jun 2014 23:59:42 -0000 Authentication-Results: sourceware.org; auth=none X-Virus-Found: No X-Spam-SWARE-Status: No, score=-2.6 required=5.0 tests=BAYES_00, RP_MATCHES_RCVD autolearn=ham version=3.3.2 X-HELO: hall.aurel32.net From: Aurelien Jarno To: libc-alpha@sourceware.org Cc: Aurelien Jarno Subject: [RFC PATCH 3/4] resolv: fix issues when using IPv6 nameservers only Date: Wed, 4 Jun 2014 01:36:42 +0200 Message-Id: <1401838603-22101-4-git-send-email-aurelien@aurel32.net> In-Reply-To: <1401838603-22101-1-git-send-email-aurelien@aurel32.net> References: <1401838603-22101-1-git-send-email-aurelien@aurel32.net> statp->nscount contains the number of servers in the statp->nsaddr_list array, which only contains IPv4 nameservers. When resolv.conf only contains IPv6 nameservers, statp->nscount equals to 0, which causes the existing code to add a 127.0.0.1 entry. Change that by checking nservall, contains the number of IPv4 + IPv6 servers instead. The same way __libc_res_nsend exits almost immediately when statp->nscount considering that no nameservers are available, while IPv6 nameservers are actually available. Change that by checking (statp->nscount + EXT(statp).nscount6) instead. --- resolv/res_init.c | 2 +- resolv/res_send.c | 2 +- 2 files changed, 2 insertions(+), 2 deletions(-) diff --git a/resolv/res_init.c b/resolv/res_init.c index 37004ab..95564af 100644 --- a/resolv/res_init.c +++ b/resolv/res_init.c @@ -427,7 +427,7 @@ __res_vinit(res_state statp, int preinit) { #endif (void) fclose(fp); } - if (__builtin_expect(statp->nscount == 0, 0)) { + if (__builtin_expect(nservall == 0, 0)) { statp->nsaddr.sin_addr = inet_makeaddr(IN_LOOPBACKNET, 1); statp->nsaddr.sin_family = AF_INET; statp->nsaddr.sin_port = htons(NAMESERVER_PORT); diff --git a/resolv/res_send.c b/resolv/res_send.c index af42b8a..08fc037 100644 --- a/resolv/res_send.c +++ b/resolv/res_send.c @@ -347,7 +347,7 @@ __libc_res_nsend(res_state statp, const u_char *buf, int buflen, { int gotsomewhere, terrno, try, v_circuit, resplen, ns, n; - if (statp->nscount == 0) { + if ((statp->nscount + EXT(statp).nscount6) == 0) { __set_errno (ESRCH); return (-1); }