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=-16.7 required=3.0 tests=BAYES_00, 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 090BCC43470 for ; Fri, 21 May 2021 09:55:52 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id DBDC06135C for ; Fri, 21 May 2021 09:55:51 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S237870AbhEUJ5N (ORCPT ); Fri, 21 May 2021 05:57:13 -0400 Received: from szxga05-in.huawei.com ([45.249.212.191]:4574 "EHLO szxga05-in.huawei.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S235792AbhEUJzU (ORCPT ); Fri, 21 May 2021 05:55:20 -0400 Received: from dggems705-chm.china.huawei.com (unknown [172.30.72.60]) by szxga05-in.huawei.com (SkyGuard) with ESMTP id 4Fmhgx0TDGzqVJd; Fri, 21 May 2021 17:51:09 +0800 (CST) Received: from dggema753-chm.china.huawei.com (10.1.198.195) by dggems705-chm.china.huawei.com (10.3.19.182) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256) id 15.1.2176.2; Fri, 21 May 2021 17:53:56 +0800 Received: from localhost.localdomain (10.69.192.56) by dggema753-chm.china.huawei.com (10.1.198.195) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256_P256) id 15.1.2176.2; Fri, 21 May 2021 17:53:56 +0800 From: Weihang Li To: , CC: , , , Weihang Li , Mike Marciniszyn , Dennis Dalessandro Subject: [PATCH v2 for-next 17/17] RDMA/rdmavt: Use refcount_t instead of atomic_t on refcount of rvt_mcast Date: Fri, 21 May 2021 17:53:45 +0800 Message-ID: <1621590825-60693-18-git-send-email-liweihang@huawei.com> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1621590825-60693-1-git-send-email-liweihang@huawei.com> References: <1621590825-60693-1-git-send-email-liweihang@huawei.com> MIME-Version: 1.0 Content-Type: text/plain X-Originating-IP: [10.69.192.56] X-ClientProxiedBy: dggems703-chm.china.huawei.com (10.3.19.180) To dggema753-chm.china.huawei.com (10.1.198.195) X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: linux-rdma@vger.kernel.org The refcount_t API will WARN on underflow and overflow of a reference counter, and avoid use-after-free risks. Increase refcount_t from 0 to 1 is regarded as there is a risk about use-after-free. So it should be set to 1 directly during initialization. Cc: Mike Marciniszyn Cc: Dennis Dalessandro Signed-off-by: Weihang Li --- drivers/infiniband/hw/hfi1/verbs.c | 3 ++- drivers/infiniband/hw/qib/qib_verbs.c | 3 ++- drivers/infiniband/sw/rdmavt/mcast.c | 11 +++++------ include/rdma/rdmavt_qp.h | 2 +- 4 files changed, 10 insertions(+), 9 deletions(-) diff --git a/drivers/infiniband/hw/hfi1/verbs.c b/drivers/infiniband/hw/hfi1/verbs.c index 5542943..d67f707 100644 --- a/drivers/infiniband/hw/hfi1/verbs.c +++ b/drivers/infiniband/hw/hfi1/verbs.c @@ -534,7 +534,8 @@ static inline void hfi1_handle_packet(struct hfi1_packet *packet, * Notify rvt_multicast_detach() if it is waiting for us * to finish. */ - if (atomic_dec_return(&mcast->refcount) <= 1) + refcount_dec(&mcast->refcount); + if (refcount_read(&mcast->refcount) <= 1) wake_up(&mcast->wait); } else { /* Get the destination QP number. */ diff --git a/drivers/infiniband/hw/qib/qib_verbs.c b/drivers/infiniband/hw/qib/qib_verbs.c index d17d034..d6a7cc9 100644 --- a/drivers/infiniband/hw/qib/qib_verbs.c +++ b/drivers/infiniband/hw/qib/qib_verbs.c @@ -336,7 +336,8 @@ void qib_ib_rcv(struct qib_ctxtdata *rcd, void *rhdr, void *data, u32 tlen) * Notify rvt_multicast_detach() if it is waiting for us * to finish. */ - if (atomic_dec_return(&mcast->refcount) <= 1) + refcount_dec(&mcast->refcount); + if (refcount_read(&mcast->refcount) <= 1) wake_up(&mcast->wait); } else { rcu_read_lock(); diff --git a/drivers/infiniband/sw/rdmavt/mcast.c b/drivers/infiniband/sw/rdmavt/mcast.c index 951abac..7746d5c 100644 --- a/drivers/infiniband/sw/rdmavt/mcast.c +++ b/drivers/infiniband/sw/rdmavt/mcast.c @@ -117,7 +117,6 @@ static struct rvt_mcast *rvt_mcast_alloc(union ib_gid *mgid, u16 lid) INIT_LIST_HEAD(&mcast->qp_list); init_waitqueue_head(&mcast->wait); - atomic_set(&mcast->refcount, 0); bail: return mcast; @@ -169,7 +168,7 @@ struct rvt_mcast *rvt_mcast_find(struct rvt_ibport *ibp, union ib_gid *mgid, } else { /* MGID/MLID must match */ if (mcast->mcast_addr.lid == lid) { - atomic_inc(&mcast->refcount); + refcount_inc(&mcast->refcount); found = mcast; } break; @@ -257,7 +256,7 @@ static int rvt_mcast_add(struct rvt_dev_info *rdi, struct rvt_ibport *ibp, list_add_tail_rcu(&mqp->list, &mcast->qp_list); - atomic_inc(&mcast->refcount); + refcount_set(&mcast->refcount, 1); rb_link_node(&mcast->rb_node, pn, n); rb_insert_color(&mcast->rb_node, &ibp->mcast_tree); @@ -410,12 +409,12 @@ int rvt_detach_mcast(struct ib_qp *ibqp, union ib_gid *gid, u16 lid) * Wait for any list walkers to finish before freeing the * list element. */ - wait_event(mcast->wait, atomic_read(&mcast->refcount) <= 1); + wait_event(mcast->wait, refcount_read(&mcast->refcount) <= 1); rvt_mcast_qp_free(delp); if (last) { - atomic_dec(&mcast->refcount); - wait_event(mcast->wait, !atomic_read(&mcast->refcount)); + refcount_dec(&mcast->refcount); + wait_event(mcast->wait, !refcount_read(&mcast->refcount)); rvt_mcast_free(mcast); spin_lock_irq(&rdi->n_mcast_grps_lock); rdi->n_mcast_grps_allocated--; diff --git a/include/rdma/rdmavt_qp.h b/include/rdma/rdmavt_qp.h index 8275954..cd19573 100644 --- a/include/rdma/rdmavt_qp.h +++ b/include/rdma/rdmavt_qp.h @@ -520,7 +520,7 @@ struct rvt_mcast { struct rvt_mcast_addr mcast_addr; struct list_head qp_list; wait_queue_head_t wait; - atomic_t refcount; + refcount_t refcount; int n_attached; }; -- 2.7.4