From patchwork Sun Jul 31 20:19:52 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Dai Ngo X-Patchwork-Id: 12933261 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 50071C00140 for ; Sun, 31 Jul 2022 20:20:06 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S237874AbiGaUUF (ORCPT ); Sun, 31 Jul 2022 16:20:05 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:35672 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231785AbiGaUUE (ORCPT ); Sun, 31 Jul 2022 16:20:04 -0400 Received: from mx0a-00069f02.pphosted.com (mx0a-00069f02.pphosted.com [205.220.165.32]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id B92C911C0D for ; Sun, 31 Jul 2022 13:20:02 -0700 (PDT) Received: from pps.filterd (m0246629.ppops.net [127.0.0.1]) by mx0b-00069f02.pphosted.com (8.17.1.5/8.17.1.5) with ESMTP id 26VB2wSm013313; Sun, 31 Jul 2022 20:20:01 GMT DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=oracle.com; h=from : to : cc : subject : date : message-id; s=corp-2022-7-12; bh=9nsw4dRJ83hYwuf/Ki//YsDD2+vzLq7e9c75JFOxRJg=; b=MmTl9gGAn4XUji4RMeeakY32359blr6x8cnZe/OOguGclTUj38dHeiLflnY7bpZrRS/B U6YR93veKBpSSiLFsRRNukRR978D9sY3ctv3y/0ECt1ugpesNrUk/G0YzdJMSu44xMmE Zf9MxMVFkDhduDRRx7jvU+JntBwf8ztJvWfKa9yq4pApFwGZCxCZ5T1hj6w8EV4/ShJr xQYGvvZS1cgTL8E935bL1t4xL2bDbYsHIF+P4mHYfTiHiJlDdd7YH00Gf6vVoAVUPU69 ZdE8kkPs2g3l+lVRR5MuxeTrf0eiUX1R9xkdVaJaWan3UYWyDPItpA61/mXW/b5juuhG Fw== Received: from iadpaimrmta02.imrmtpd1.prodappiadaev1.oraclevcn.com (iadpaimrmta02.appoci.oracle.com [147.154.18.20]) by mx0b-00069f02.pphosted.com (PPS) with ESMTPS id 3hmvh9hsyq-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Sun, 31 Jul 2022 20:20:01 +0000 Received: from pps.filterd (iadpaimrmta02.imrmtpd1.prodappiadaev1.oraclevcn.com [127.0.0.1]) by iadpaimrmta02.imrmtpd1.prodappiadaev1.oraclevcn.com (8.17.1.5/8.17.1.5) with ESMTP id 26VHZRGT030892; Sun, 31 Jul 2022 20:20:00 GMT Received: from pps.reinject (localhost [127.0.0.1]) by iadpaimrmta02.imrmtpd1.prodappiadaev1.oraclevcn.com (PPS) with ESMTPS id 3hmu30r6dk-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Sun, 31 Jul 2022 20:19:59 +0000 Received: from iadpaimrmta02.imrmtpd1.prodappiadaev1.oraclevcn.com (iadpaimrmta02.imrmtpd1.prodappiadaev1.oraclevcn.com [127.0.0.1]) by pps.reinject (8.17.1.5/8.17.1.5) with ESMTP id 26VKJxKa002522; Sun, 31 Jul 2022 20:19:59 GMT Received: from ca-common-hq.us.oracle.com (ca-common-hq.us.oracle.com [10.211.9.209]) by iadpaimrmta02.imrmtpd1.prodappiadaev1.oraclevcn.com (PPS) with ESMTP id 3hmu30r6de-1; Sun, 31 Jul 2022 20:19:59 +0000 From: Dai Ngo To: chuck.lever@oracle.com, olga.kornievskaia@gmail.com Cc: linux-nfs@vger.kernel.org Subject: [PATCH] NFSD: fix use-after-free on source server when doing inter-server copy Date: Sun, 31 Jul 2022 13:19:52 -0700 Message-Id: <1659298792-5735-1-git-send-email-dai.ngo@oracle.com> X-Mailer: git-send-email 1.8.3.1 X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.205,Aquarius:18.0.883,Hydra:6.0.517,FMLib:17.11.122.1 definitions=2022-07-31_15,2022-07-28_02,2022-06-22_01 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 mlxscore=0 malwarescore=0 spamscore=0 suspectscore=0 adultscore=0 mlxlogscore=999 bulkscore=0 phishscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2206140000 definitions=main-2207310099 X-Proofpoint-ORIG-GUID: 1HJRM7MCeqj3S6-tc6WBz--D9CdhqCFl X-Proofpoint-GUID: 1HJRM7MCeqj3S6-tc6WBz--D9CdhqCFl Precedence: bulk List-ID: X-Mailing-List: linux-nfs@vger.kernel.org Use-after-free occurred when the laundromat tried to free expired cpntf_state entry on the s2s_cp_stateids list after inter-server copy completed. The sc_cp_list that the expired copy state was inserted on was already freed. When COPY completes, the Linux client normally sends LOCKU(lock_state x), FREE_STATEID(lock_state x) and CLOSE(open_state y) to the source server. The nfs4_put_stid call from nfsd4_free_stateid cleans up the copy state from the s2s_cp_stateids list before freeing the lock state's stid. However, sometimes the CLOSE was sent before the FREE_STATEID request. When this happens, the nfsd4_close_open_stateid call from nfsd4_close frees all lock states on its st_locks list without cleaning up the copy state on the sc_cp_list list. When the time the FREE_STATEID arrives the server returns BAD_STATEID since the lock state was freed. This causes the use-after-free error to occur when the laundromat tries to free the expired cpntf_state. This patch adds a call to nfs4_free_cpntf_statelist in nfsd4_close_open_stateid to clean up the copy state before calling free_ol_stateid_reaplist to free the lock state's stid on the reaplist. Signed-off-by: Dai Ngo --- fs/nfsd/nfs4state.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/fs/nfsd/nfs4state.c b/fs/nfsd/nfs4state.c index 9409a0dc1b76..749f51dff5c7 100644 --- a/fs/nfsd/nfs4state.c +++ b/fs/nfsd/nfs4state.c @@ -6608,6 +6608,7 @@ static void nfsd4_close_open_stateid(struct nfs4_ol_stateid *s) struct nfs4_client *clp = s->st_stid.sc_client; bool unhashed; LIST_HEAD(reaplist); + struct nfs4_ol_stateid *stp; spin_lock(&clp->cl_lock); unhashed = unhash_open_stateid(s, &reaplist); @@ -6616,6 +6617,8 @@ static void nfsd4_close_open_stateid(struct nfs4_ol_stateid *s) if (unhashed) put_ol_stateid_locked(s, &reaplist); spin_unlock(&clp->cl_lock); + list_for_each_entry(stp, &reaplist, st_locks) + nfs4_free_cpntf_statelist(clp->net, &stp->st_stid); free_ol_stateid_reaplist(&reaplist); } else { spin_unlock(&clp->cl_lock);