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=-9.0 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_PASS,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 63692C282CE for ; Mon, 11 Feb 2019 16:10:18 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 32D7621B18 for ; Mon, 11 Feb 2019 16:10:18 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1549901418; bh=fXCFkNbYIbfhyWhYvj/5WF4gvzzKw6XM/wkj2Y2/KUM=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=0KGM3U3NbSouOV1FyHZp4quistZ+5niO+eUeIAXGqzQQ+ylez6EXSeS7WpPHo8CrX zOUfZQyGCMvnqdv8CTfjkPXDS01gbTG4hlltc2DYlZMSWrWCeSkXYhAI1XFvexymL+ fRrUtZuivp78LXlsS1ULABUR0/Qade0GARrQSMvI= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729315AbfBKQKN (ORCPT ); Mon, 11 Feb 2019 11:10:13 -0500 Received: from mail.kernel.org ([198.145.29.99]:58154 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729266AbfBKOYv (ORCPT ); Mon, 11 Feb 2019 09:24:51 -0500 Received: from localhost (5356596B.cm-6-7b.dynamic.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 106BF20821; Mon, 11 Feb 2019 14:24:49 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1549895090; bh=fXCFkNbYIbfhyWhYvj/5WF4gvzzKw6XM/wkj2Y2/KUM=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=OPMM1d4A7HHK9q0biEv0tJx2QYqvUX3ypREYhuc1eORBRbgTXcTVS1OnqOpiVqxOt dPXjZFylHwx5mx+9hckIiO6woDfx1L9dWgv3tOUEro8cgNsnhvlw4OJhfh+sb31lZg eT7k10P967RmiuinE1YcJUVn9Fr9GrCMQ/6EAWfM= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Anatoly Trosinenko , "J. Bruce Fields" , Sasha Levin Subject: [PATCH 4.20 089/352] nfsd4: fix crash on writing v4_end_grace before nfsd startup Date: Mon, 11 Feb 2019 15:15:16 +0100 Message-Id: <20190211141851.588374355@linuxfoundation.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20190211141846.543045703@linuxfoundation.org> References: <20190211141846.543045703@linuxfoundation.org> User-Agent: quilt/0.65 X-stable: review X-Patchwork-Hint: ignore MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: stable-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org 4.20-stable review patch. If anyone has any objections, please let me know. ------------------ [ Upstream commit 62a063b8e7d1db684db3f207261a466fa3194e72 ] Anatoly Trosinenko reports that this: 1) Checkout fresh master Linux branch (tested with commit e195ca6cb) 2) Copy x84_64-config-4.14 to .config, then enable NFS server v4 and build 3) From `kvm-xfstests shell`: results in NULL dereference in locks_end_grace. Check that nfsd has been started before trying to end the grace period. Reported-by: Anatoly Trosinenko Signed-off-by: J. Bruce Fields Signed-off-by: Sasha Levin --- fs/nfsd/nfsctl.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/fs/nfsd/nfsctl.c b/fs/nfsd/nfsctl.c index 6384c9b94898..b33f9785b756 100644 --- a/fs/nfsd/nfsctl.c +++ b/fs/nfsd/nfsctl.c @@ -1126,6 +1126,8 @@ static ssize_t write_v4_end_grace(struct file *file, char *buf, size_t size) case 'Y': case 'y': case '1': + if (nn->nfsd_serv) + return -EBUSY; nfsd4_end_grace(nn); break; default: -- 2.19.1