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=-8.8 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,UNPARSEABLE_RELAY, 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 86529C43613 for ; Fri, 21 Jun 2019 14:09:47 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 5D51A208C3 for ; Fri, 21 Jun 2019 14:09:47 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=oracle.com header.i=@oracle.com header.b="jPFLSyAD" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726307AbfFUOJq (ORCPT ); Fri, 21 Jun 2019 10:09:46 -0400 Received: from aserp2120.oracle.com ([141.146.126.78]:38374 "EHLO aserp2120.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725985AbfFUOJp (ORCPT ); Fri, 21 Jun 2019 10:09:45 -0400 Received: from pps.filterd (aserp2120.oracle.com [127.0.0.1]) by aserp2120.oracle.com (8.16.0.27/8.16.0.27) with SMTP id x5LE4EhB119871; Fri, 21 Jun 2019 14:09:23 GMT DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=oracle.com; h=from : to : cc : subject : date : message-id; s=corp-2018-07-02; bh=QDLZN1HgJ+/BQ+FyQff3Jo34xNZRRZDqv9MXgPbWNrI=; b=jPFLSyADEMtahQwESDqTZ0nwlF7Fd6xUsP4ziR2gAHIYUG4qtdnOwGRJoNOMz+phfRUw R5fILir7lic56V/N2vMtg+x26494+nfK8LjCULlbn1feYyGZ5obqWb+0BxoIlSKZDsc6 CN+SpDTcbOvP0C2qG+MygUfqUs4rnV18cQce38IO6YIXEjiAR6tOCXOIlWVHqDTSmor2 6wz65p78bUUrtof60Fqpbb48238IG64oEf5YNURN5VpmPv3PBj6aDv1Hfz8tHc2C6ja8 sap9ggtkSl3/EmoafiT7xR2jU5wP2VdDWTiq1kOSkRovKsbtbhY1YUSa1suERvLw7NC5 9Q== Received: from userp3030.oracle.com (userp3030.oracle.com [156.151.31.80]) by aserp2120.oracle.com with ESMTP id 2t7809pp7d-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Fri, 21 Jun 2019 14:09:23 +0000 Received: from pps.filterd (userp3030.oracle.com [127.0.0.1]) by userp3030.oracle.com (8.16.0.27/8.16.0.27) with SMTP id x5LE7g94137107; Fri, 21 Jun 2019 14:09:22 GMT Received: from userv0122.oracle.com (userv0122.oracle.com [156.151.31.75]) by userp3030.oracle.com with ESMTP id 2t77yp7k0c-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Fri, 21 Jun 2019 14:09:22 +0000 Received: from abhmp0022.oracle.com (abhmp0022.oracle.com [141.146.116.28]) by userv0122.oracle.com (8.14.4/8.14.4) with ESMTP id x5LE9LXJ025111; Fri, 21 Jun 2019 14:09:21 GMT Received: from dm-oel.no.oracle.com (/10.172.157.165) by default (Oracle Beehive Gateway v4.0) with ESMTP ; Fri, 21 Jun 2019 07:09:21 -0700 From: Dag Moxnes To: dag.moxnes@oracle.com, dledford@redhat.com, jgg@ziepe.ca, leon@kernel.org Cc: linux-rdma@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH] RDMA/core: Fix race when resolving IP address Date: Fri, 21 Jun 2019 16:09:16 +0200 Message-Id: <1561126156-10162-1-git-send-email-dag.moxnes@oracle.com> X-Mailer: git-send-email 1.7.1 X-Proofpoint-Virus-Version: vendor=nai engine=6000 definitions=9294 signatures=668687 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 suspectscore=0 malwarescore=0 phishscore=0 bulkscore=0 spamscore=0 mlxscore=0 mlxlogscore=999 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1810050000 definitions=main-1906210118 X-Proofpoint-Virus-Version: vendor=nai engine=6000 definitions=9294 signatures=668687 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 priorityscore=1501 malwarescore=0 suspectscore=0 phishscore=0 bulkscore=0 spamscore=0 clxscore=1011 lowpriorityscore=0 mlxscore=0 impostorscore=0 mlxlogscore=999 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1810050000 definitions=main-1906210118 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Use neighbour lock when copying MAC address from neighbour data struct in dst_fetch_ha. When not using the lock, it is possible for the function to race with neigh_update, causing it to copy an invalid MAC address. It is possible to provoke this error by calling rdma_resolve_addr in a tight loop, while deleting the corresponding ARP entry in another tight loop. Signed-off-by: Dag Moxnes Change-Id: I3c5f982b304457f0a83ea7def2fac70315ed38b4 --- drivers/infiniband/core/addr.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) diff --git a/drivers/infiniband/core/addr.c b/drivers/infiniband/core/addr.c index 2f7d141598..e4945fd1bb 100644 --- a/drivers/infiniband/core/addr.c +++ b/drivers/infiniband/core/addr.c @@ -333,12 +333,16 @@ static int dst_fetch_ha(const struct dst_entry *dst, if (!n) return -ENODATA; + read_lock_bh(&n->lock) if (!(n->nud_state & NUD_VALID)) { - neigh_event_send(n, NULL); ret = -ENODATA; } else { memcpy(dev_addr->dst_dev_addr, n->ha, MAX_ADDR_LEN); } + read_unlock_bh(&n->lock); + + if (ret) + neigh_event_send(n, NULL); neigh_release(n); -- 2.20.1