From patchwork Mon Jan 18 11:35:05 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Greg Kroah-Hartman X-Patchwork-Id: 366069 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=-18.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID, DKIM_VALID_AU, HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER, INCLUDES_PATCH, MAILING_LIST_MULTI, SPF_HELO_NONE, SPF_PASS, URIBL_BLOCKED, 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 E75ADC433E6 for ; Mon, 18 Jan 2021 12:27:04 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id B29DC22286 for ; Mon, 18 Jan 2021 12:27:04 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2391517AbhARM1B (ORCPT ); Mon, 18 Jan 2021 07:27:01 -0500 Received: from mail.kernel.org ([198.145.29.99]:39632 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2390842AbhARLpv (ORCPT ); Mon, 18 Jan 2021 06:45:51 -0500 Received: by mail.kernel.org (Postfix) with ESMTPSA id 645F022D73; Mon, 18 Jan 2021 11:45:23 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1610970323; bh=/od9EWMi4fi2vmHVTsRuSFqgzqQJbf4Ro+C3AIJVeqM=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=SfSg2zXyKIs7MWQ1QjrHkiruFdFNVctgirXXsyMXyA8MCQ0ZvT+Y4K10Ff9NObqkR MsLtGb8nOrTAbBlZI/MpFqQUszGR9QbAlycIBq1DRcTCYE8mUnwuGyprdCvvk9QEmu i9ckjYBi8qWkjlEc6c8ki6/2caTc9icB34XgkueI= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Trond Myklebust Subject: [PATCH 5.10 130/152] NFS: nfs_igrab_and_active must first reference the superblock Date: Mon, 18 Jan 2021 12:35:05 +0100 Message-Id: <20210118113358.954705201@linuxfoundation.org> X-Mailer: git-send-email 2.30.0 In-Reply-To: <20210118113352.764293297@linuxfoundation.org> References: <20210118113352.764293297@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Trond Myklebust commit 896567ee7f17a8a736cda8a28cc987228410a2ac upstream. Before referencing the inode, we must ensure that the superblock can be referenced. Otherwise, we can end up with iput() calling superblock operations that are no longer valid or accessible. Fixes: ea7c38fef0b7 ("NFSv4: Ensure we reference the inode for return-on-close in delegreturn") Signed-off-by: Trond Myklebust Signed-off-by: Greg Kroah-Hartman --- fs/nfs/internal.h | 12 +++++++----- 1 file changed, 7 insertions(+), 5 deletions(-) --- a/fs/nfs/internal.h +++ b/fs/nfs/internal.h @@ -605,12 +605,14 @@ extern void nfs4_test_session_trunk(stru static inline struct inode *nfs_igrab_and_active(struct inode *inode) { - inode = igrab(inode); - if (inode != NULL && !nfs_sb_active(inode->i_sb)) { - iput(inode); - inode = NULL; + struct super_block *sb = inode->i_sb; + + if (sb && nfs_sb_active(sb)) { + if (igrab(inode)) + return inode; + nfs_sb_deactive(sb); } - return inode; + return NULL; } static inline void nfs_iput_and_deactive(struct inode *inode)