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=-9.8 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 2FA3EC4321A for ; Fri, 28 Jun 2019 08:49:36 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id EFA09205F4 for ; Fri, 28 Jun 2019 08:49:35 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=oracle.com header.i=@oracle.com header.b="yMzomvOv" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726663AbfF1Ite (ORCPT ); Fri, 28 Jun 2019 04:49:34 -0400 Received: from userp2130.oracle.com ([156.151.31.86]:35882 "EHLO userp2130.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726240AbfF1Ite (ORCPT ); Fri, 28 Jun 2019 04:49:34 -0400 Received: from pps.filterd (userp2130.oracle.com [127.0.0.1]) by userp2130.oracle.com (8.16.0.27/8.16.0.27) with SMTP id x5S8mxHV040376; Fri, 28 Jun 2019 08:49:12 GMT DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=oracle.com; h=from : to : cc : subject : date : message-id : mime-version : content-type : content-transfer-encoding; s=corp-2018-07-02; bh=4D8QFL/3XbTVzEiMWzUU7hVQJVuawiGGxMYhiOpgGyY=; b=yMzomvOvUm+rN7I3ED3veGQ+SjgwPUkyq4CrtnZOsBPhSqvSVgmpGlmdc1wVaLFC13AY 2amGjNEHP9B4veJ50Pz2Leo9Rio8iMFvVkCDp2eY08D4OK4CENV49G88buqSvQ6iojMu v0jV1hN6whtoWD2acAwl3XY5Fc2dqqu4ZjAJ/ssdFMkt908BrDaYmsG47TRoUUxzSyBp QkqGCD6aH70sCnwdz2sG3+j8OKh73L4SuGOOuAIEtOcHuFRRDZzhYhHMdQEY3vf2UoLD DQ/T7cPRL738G9/RATjUgphoP2Uw85QkFCRKNHQJJ9zPuZqc+XRKMuldGEMsKaU+VDXT eQ== Received: from userp3030.oracle.com (userp3030.oracle.com [156.151.31.80]) by userp2130.oracle.com with ESMTP id 2t9brtmj18-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Fri, 28 Jun 2019 08:49:12 +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 x5S8mIAv109968; Fri, 28 Jun 2019 08:49:12 GMT Received: from aserv0121.oracle.com (aserv0121.oracle.com [141.146.126.235]) by userp3030.oracle.com with ESMTP id 2t99f5fjgv-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Fri, 28 Jun 2019 08:49:12 +0000 Received: from abhmp0019.oracle.com (abhmp0019.oracle.com [141.146.116.25]) by aserv0121.oracle.com (8.14.4/8.13.8) with ESMTP id x5S8nAId024954; Fri, 28 Jun 2019 08:49:10 GMT Received: from dm-oel.no.oracle.com (/10.172.157.165) by default (Oracle Beehive Gateway v4.0) with ESMTP ; Fri, 28 Jun 2019 01:49:10 -0700 From: Dag Moxnes To: dag.moxnes@oracle.com, dledford@redhat.com, jgg@ziepe.ca, leon@kernel.org, parav@mellanox.com Cc: linux-rdma@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH v2] RDMA/core: Fix race when resolving IP address Date: Fri, 28 Jun 2019 10:49:23 +0200 Message-Id: <1561711763-24705-1-git-send-email-dag.moxnes@oracle.com> X-Mailer: git-send-email 1.7.1 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit X-Proofpoint-Virus-Version: vendor=nai engine=6000 definitions=9301 signatures=668688 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-1906280104 X-Proofpoint-Virus-Version: vendor=nai engine=6000 definitions=9301 signatures=668688 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 priorityscore=1501 malwarescore=0 suspectscore=0 phishscore=0 bulkscore=0 spamscore=0 clxscore=1015 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-1906280104 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 Signed-off-by: Håkon Bugge --- v1 -> v2: * Modified implementation to improve readability --- drivers/infiniband/core/addr.c | 9 ++++++--- 1 file changed, 6 insertions(+), 3 deletions(-) diff --git a/drivers/infiniband/core/addr.c b/drivers/infiniband/core/addr.c index 2f7d141598..51323ffbc5 100644 --- a/drivers/infiniband/core/addr.c +++ b/drivers/infiniband/core/addr.c @@ -333,11 +333,14 @@ static int dst_fetch_ha(const struct dst_entry *dst, if (!n) return -ENODATA; - if (!(n->nud_state & NUD_VALID)) { + read_lock_bh(&n->lock); + if (n->nud_state & NUD_VALID) { + memcpy(dev_addr->dst_dev_addr, n->ha, MAX_ADDR_LEN); + read_unlock_bh(&n->lock); + } else { + read_unlock_bh(&n->lock); neigh_event_send(n, NULL); ret = -ENODATA; - } else { - memcpy(dev_addr->dst_dev_addr, n->ha, MAX_ADDR_LEN); } neigh_release(n); -- 2.20.1