From patchwork Fri Mar 8 20:45:12 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Florian Weimer X-Patchwork-Id: 1053705 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Authentication-Results: ozlabs.org; spf=pass (mailfrom) smtp.mailfrom=sourceware.org (client-ip=209.132.180.131; helo=sourceware.org; envelope-from=libc-alpha-return-100512-incoming=patchwork.ozlabs.org@sourceware.org; receiver=) Authentication-Results: ozlabs.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: ozlabs.org; dkim=pass (1024-bit key; secure) header.d=sourceware.org header.i=@sourceware.org header.b="hWadDldt"; dkim-atps=neutral Received: from sourceware.org (server1.sourceware.org [209.132.180.131]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ozlabs.org (Postfix) with ESMTPS id 44GKJt3fQHz9ryj for ; Sat, 9 Mar 2019 07:45:50 +1100 (AEDT) DomainKey-Signature: a=rsa-sha1; c=nofws; d=sourceware.org; h=list-id :list-unsubscribe:list-subscribe:list-archive:list-post :list-help:sender:date:to:subject:mime-version:content-type :content-transfer-encoding:message-id:from; q=dns; s=default; b= aTnKelhzhcG7bGp5mgRR9yhKkbHxP8bgUxwWw1OMmdfLsMtZzj+j0AU0twTrbJhq 0lbq/kaC3qeGIlgD3kHp04OVznHMtGhuU2ePmZ8W/uIiTm5eO5grfZXKTBYgDpN9 ArJj1N3JKmYNfcqnQxJJTta3CXzKvEqcCVGfGhvfHkM= DKIM-Signature: v=1; a=rsa-sha1; c=relaxed; d=sourceware.org; h=list-id :list-unsubscribe:list-subscribe:list-archive:list-post :list-help:sender:date:to:subject:mime-version:content-type :content-transfer-encoding:message-id:from; s=default; bh=gwG6mq QQFEVkm0ecishdNMdtNC8=; b=hWadDldt0bfP4SNBwr1DIPd6HV8AOia608vpE9 IMKkU5yxrGZxAZUVP06S1XYJUtIVWz52aM4omJ8Pecn2AT73lRbC+mV9TLZawper /yysG6SbhnVk0QA+MQH9Xq2zldsy5sqsUPBJRes/qxl9GG3/TMQ9Y+l0h6O0tF/e k7Q5Y= Received: (qmail 19796 invoked by alias); 8 Mar 2019 20:45:42 -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 19631 invoked by uid 89); 8 Mar 2019 20:45:20 -0000 Authentication-Results: sourceware.org; auth=none X-Spam-SWARE-Status: No, score=-19.8 required=5.0 tests=AWL, BAYES_00, GIT_PATCH_0, GIT_PATCH_1, GIT_PATCH_2, GIT_PATCH_3, SPF_HELO_PASS autolearn=ham version=3.3.1 spammy=consistently X-HELO: mx1.redhat.com Date: Fri, 08 Mar 2019 21:45:12 +0100 To: libc-alpha@sourceware.org Subject: [PATCH] nss_dns: More consistency in corrupt message handling in getnetby* User-Agent: Heirloom mailx 12.5 7/5/10 MIME-Version: 1.0 Message-Id: <20190308204512.4EC1780DD6B5@oldenburg2.str.redhat.com> From: Florian Weimer If a parse error is encountered, fail with NO_RECOVERY and NSS_STATUS_UNAVAIL. 2019-03-08 Florian Weimer * resolv/nss_dns/dns-network.c (getanswer_r): Handle unparseable messages more consistently. diff --git a/resolv/nss_dns/dns-network.c b/resolv/nss_dns/dns-network.c index 9c0082d270..68266d57c9 100644 --- a/resolv/nss_dns/dns-network.c +++ b/resolv/nss_dns/dns-network.c @@ -336,14 +336,11 @@ getanswer_r (const querybuf *answer, int anslen, struct netent *result, bp[0] = '\0'; if (n < 0) - break; + goto bad_message; cp += n; if (end_of_message - cp < 10) - { - __set_h_errno (NO_RECOVERY); - return NSS_STATUS_UNAVAIL; - } + goto bad_message; int type, class; GETSHORT (type, cp); @@ -352,10 +349,7 @@ getanswer_r (const querybuf *answer, int anslen, struct netent *result, uint16_t rdatalen; GETSHORT (rdatalen, cp); if (end_of_message - cp < rdatalen) - { - __set_h_errno (NO_RECOVERY); - return NSS_STATUS_UNAVAIL; - } + goto bad_message; if (class == C_IN && type == T_PTR) { @@ -370,13 +364,7 @@ getanswer_r (const querybuf *answer, int anslen, struct netent *result, } if (n < 0) - { - /* XXX What does this mean? The original form from bind - returns NULL. Incrementing cp has no effect in any case. - What should I return here. ??? */ - cp += n; - return NSS_STATUS_UNAVAIL; - } + goto bad_message; cp += rdatalen; if (alias_pointer + 2 < &net_data->aliases[MAX_NR_ALIASES]) {