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=-6.0 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE, SPF_PASS,T_DKIMWL_WL_HIGH,URIBL_BLOCKED,USER_AGENT_GIT autolearn=unavailable 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 D5242C282E1 for ; Thu, 23 May 2019 19:45:44 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id A533F20881 for ; Thu, 23 May 2019 19:45:44 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1558640744; bh=7uXs0Hd9BHczWfI9QjqAQuZuSbC0kbYMC9PdSh6KVRg=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=A0AoZdUqPB3Epg3sNMKoTN5FiuISML5tOEcOKiE7i4c70rC6p2cCWS6PKQV/ltkS4 YNqokY32QhkQ8SbLaT+ZnKOQ5P4KPUJAL15bscAel1NAQXFZy5/lo48sgcda3aJDY6 NhgmecaHEPShrasBYdSjj5N6SjyJ3ted2rTeolNE= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2388417AbfEWTPS (ORCPT ); Thu, 23 May 2019 15:15:18 -0400 Received: from mail.kernel.org ([198.145.29.99]:49518 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2388918AbfEWTPO (ORCPT ); Thu, 23 May 2019 15:15:14 -0400 Received: from localhost (83-86-89-107.cable.dynamic.v4.ziggo.nl [83.86.89.107]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 60ED520863; Thu, 23 May 2019 19:15:13 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1558638913; bh=7uXs0Hd9BHczWfI9QjqAQuZuSbC0kbYMC9PdSh6KVRg=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=pGV2yy0J2vzn1OWzGb6Q27/X9N4UIyh43rXAe2m65Paxhap+ODSUvE/tGrWcuABD/ XZ2XfwL/rOmPKJpBqt1dx/z+dOLHmoMUUHXIfCQnnkLasHzpNggDFyc8+dpMhdYxW5 gs9HkXWlsV4KTQjcpNQmsBj62/OkJryRRtT55HaI= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Xiao Ni , NeilBrown , Yufen Yu , Song Liu Subject: [PATCH 4.19 027/114] md: add mddev->pers to avoid potential NULL pointer dereference Date: Thu, 23 May 2019 21:05:26 +0200 Message-Id: <20190523181734.327465301@linuxfoundation.org> X-Mailer: git-send-email 2.21.0 In-Reply-To: <20190523181731.372074275@linuxfoundation.org> References: <20190523181731.372074275@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Yufen Yu commit ee37e62191a59d253fc916b9fc763deb777211e2 upstream. When doing re-add, we need to ensure rdev->mddev->pers is not NULL, which can avoid potential NULL pointer derefence in fallowing add_bound_rdev(). Fixes: a6da4ef85cef ("md: re-add a failed disk") Cc: Xiao Ni Cc: NeilBrown Cc: # 4.4+ Reviewed-by: NeilBrown Signed-off-by: Yufen Yu Signed-off-by: Song Liu Signed-off-by: Greg Kroah-Hartman --- drivers/md/md.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) --- a/drivers/md/md.c +++ b/drivers/md/md.c @@ -2860,8 +2860,10 @@ state_store(struct md_rdev *rdev, const err = 0; } } else if (cmd_match(buf, "re-add")) { - if (test_bit(Faulty, &rdev->flags) && (rdev->raid_disk == -1) && - rdev->saved_raid_disk >= 0) { + if (!rdev->mddev->pers) + err = -EINVAL; + else if (test_bit(Faulty, &rdev->flags) && (rdev->raid_disk == -1) && + rdev->saved_raid_disk >= 0) { /* clear_bit is performed _after_ all the devices * have their local Faulty bit cleared. If any writes * happen in the meantime in the local node, they