From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-16.3 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id BF917C433E0 for ; Tue, 9 Feb 2021 05:19:45 +0000 (UTC) Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [216.205.24.124]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 4134F64EAA for ; Tue, 9 Feb 2021 05:19:45 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 4134F64EAA Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=tempfail smtp.mailfrom=dm-devel-bounces@redhat.com DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1612847984; h=from:from:sender:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references:list-id:list-help: list-unsubscribe:list-subscribe:list-post; bh=qwEfUozu3QPszTtx9nN45u0X/PGmH53wABJBJTiy3oc=; b=c3Kt0CIoB9SkFTmRzr2axoci6n4nBI1q6GX5ORUAEg+MpL//phsD1wa94XqR03e8gp8cnK Wo/FkZfx9R7oOIRVmi5WyxiMp297q5SGwVdDz8w6hymTChQhFIKapvZP3yUmXccKNT7bhd YBICzbvSmC04B+YgxibIAY4FKFF/840= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-557-BPA3QmMIOP6CTut7ubHtTA-1; Tue, 09 Feb 2021 00:19:41 -0500 X-MC-Unique: BPA3QmMIOP6CTut7ubHtTA-1 Received: from smtp.corp.redhat.com (int-mx03.intmail.prod.int.phx2.redhat.com [10.5.11.13]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id C70586D4E3; Tue, 9 Feb 2021 05:19:36 +0000 (UTC) Received: from colo-mx.corp.redhat.com (colo-mx01.intmail.prod.int.phx2.redhat.com [10.5.11.20]) by smtp.corp.redhat.com (Postfix) with ESMTPS id AA1B86F97E; Tue, 9 Feb 2021 05:19:36 +0000 (UTC) Received: from lists01.pubmisc.prod.ext.phx2.redhat.com (lists01.pubmisc.prod.ext.phx2.redhat.com [10.5.19.33]) by colo-mx.corp.redhat.com (Postfix) with ESMTP id 5802918095CB; Tue, 9 Feb 2021 05:19:36 +0000 (UTC) Received: from smtp.corp.redhat.com (int-mx08.intmail.prod.int.phx2.redhat.com [10.5.11.23]) by lists01.pubmisc.prod.ext.phx2.redhat.com (8.13.8/8.13.8) with ESMTP id 1195JZsM029782 for ; Tue, 9 Feb 2021 00:19:35 -0500 Received: by smtp.corp.redhat.com (Postfix) id 84BE019C71; Tue, 9 Feb 2021 05:19:35 +0000 (UTC) Received: from octiron.msp.redhat.com (octiron.msp.redhat.com [10.15.80.209]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 0C4FF19C78; Tue, 9 Feb 2021 05:19:30 +0000 (UTC) Received: from octiron.msp.redhat.com (localhost.localdomain [127.0.0.1]) by octiron.msp.redhat.com (8.14.9/8.14.9) with ESMTP id 1195JTgB008855; Mon, 8 Feb 2021 23:19:29 -0600 Received: (from bmarzins@localhost) by octiron.msp.redhat.com (8.14.9/8.14.9/Submit) id 1195JT3t008854; Mon, 8 Feb 2021 23:19:29 -0600 From: Benjamin Marzinski To: Christophe Varoqui Date: Mon, 8 Feb 2021 23:19:26 -0600 Message-Id: <1612847967-8813-2-git-send-email-bmarzins@redhat.com> In-Reply-To: <1612847967-8813-1-git-send-email-bmarzins@redhat.com> References: <1612847967-8813-1-git-send-email-bmarzins@redhat.com> X-Scanned-By: MIMEDefang 2.84 on 10.5.11.23 X-loop: dm-devel@redhat.com Cc: device-mapper development , Chongyun Wu , Martin Wilck Subject: [dm-devel] [PATCH 1/2] libmultipath: fix use-after-free in uev_add_path X-BeenThere: dm-devel@redhat.com X-Mailman-Version: 2.1.12 Precedence: junk List-Id: device-mapper development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Sender: dm-devel-bounces@redhat.com Errors-To: dm-devel-bounces@redhat.com X-Scanned-By: MIMEDefang 2.79 on 10.5.11.13 Authentication-Results: relay.mimecast.com; auth=pass smtp.auth=CUSA124A263 smtp.mailfrom=dm-devel-bounces@redhat.com X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit if ev_remove_path() returns success the path has very likely been deleted. However, if pathinfo() returned something besides PATHINFO_OK, but ev_remove_path() succeeded, uev_add_path() was still accessing the the path afterwards, which would likely cause a use-after-free error. Insted, uev_add_path() should only continue to access the path if ev_remove_path() didn't succeed. Signed-off-by: Benjamin Marzinski --- multipathd/main.c | 15 +++++++-------- 1 file changed, 7 insertions(+), 8 deletions(-) diff --git a/multipathd/main.c b/multipathd/main.c index 425492a9..19679848 100644 --- a/multipathd/main.c +++ b/multipathd/main.c @@ -890,13 +890,7 @@ uev_add_path (struct uevent *uev, struct vectors * vecs, int need_do_map) */ pp->mpp = prev_mpp; ret = ev_remove_path(pp, vecs, true); - if (r == PATHINFO_OK && !ret) - /* - * Path successfully freed, move on to - * "new path" code path below - */ - pp = NULL; - else { + if (ret != 0) { /* * Failure in ev_remove_path will keep * path in pathvec in INIT_REMOVED state @@ -907,7 +901,12 @@ uev_add_path (struct uevent *uev, struct vectors * vecs, int need_do_map) dm_fail_path(pp->mpp->alias, pp->dev_t); condlog(1, "%s: failed to re-add path still mapped in %s", pp->dev, pp->mpp->alias); - } + } else if (r == PATHINFO_OK) + /* + * Path successfully freed, move on to + * "new path" code path below + */ + pp = NULL; } else if (r == PATHINFO_SKIPPED) { condlog(3, "%s: remove blacklisted path", uev->kernel); -- 2.17.2 -- dm-devel mailing list dm-devel@redhat.com https://www.redhat.com/mailman/listinfo/dm-devel