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=-9.1 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_PASS,USER_AGENT_GIT 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 660B9C282C8 for ; Mon, 28 Jan 2019 16:14:16 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 2C23421741 for ; Mon, 28 Jan 2019 16:14:16 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1548692056; bh=4XSvo/1exxtw/Vykv7ljN8jvyJpyeLsXHEWoBA5LyBs=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=MCzJ1jOv8YhfYdICDE7mRSb4i69nMOuQVlu2ENdQxOdNFOlvly7fSMU02FYLJ3Gj7 +qAYAgToxRMfxv7e1oppAW0Ww/5PZPbDmw+CoM4VZLgwWoOWSQjGh6WCyP1WiBnF/u mtikDXHcjCIoc3WL1z95Ko94xbrne9cphxS79ZIk= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2387595AbfA1QOO (ORCPT ); Mon, 28 Jan 2019 11:14:14 -0500 Received: from mail.kernel.org ([198.145.29.99]:43332 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1732851AbfA1QOK (ORCPT ); Mon, 28 Jan 2019 11:14:10 -0500 Received: from sasha-vm.mshome.net (c-73-47-72-35.hsd1.nh.comcast.net [73.47.72.35]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 459D02086C; Mon, 28 Jan 2019 16:14:09 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1548692050; bh=4XSvo/1exxtw/Vykv7ljN8jvyJpyeLsXHEWoBA5LyBs=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=teZuAvdxKXV0ZsG8JCicGUXKLhvR3RTUJtx8nB69sG1+suBh0s7yKd0T4P6/pTp1y RVMDyiPSIySFGqeIweylR54OxOSAOcexnqHKTxepbhrOtjW3XsvBmtSyUlqAYDZHmB ovqhI5k6Ok66zmLfznljmoKxGO4M/uZqOJVAf098= From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: "J. Bruce Fields" , Sasha Levin , linux-nfs@vger.kernel.org Subject: [PATCH AUTOSEL 4.14 053/170] nfsd4: fix crash on writing v4_end_grace before nfsd startup Date: Mon, 28 Jan 2019 11:10:03 -0500 Message-Id: <20190128161200.55107-53-sashal@kernel.org> X-Mailer: git-send-email 2.19.1 In-Reply-To: <20190128161200.55107-1-sashal@kernel.org> References: <20190128161200.55107-1-sashal@kernel.org> MIME-Version: 1.0 X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: "J. Bruce Fields" [ 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 6493df6b1bd5..4b8ebcc6b183 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