From patchwork Fri Oct 20 07:23:38 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Reshetova, Elena" X-Patchwork-Id: 10019023 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id D6588602CB for ; Fri, 20 Oct 2017 07:26:35 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id C64D228EAC for ; Fri, 20 Oct 2017 07:26:35 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id BAB6E28ECC; Fri, 20 Oct 2017 07:26:35 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-3.7 required=2.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID, RCVD_IN_DNSWL_MED, RCVD_IN_SORBS_SPAM autolearn=unavailable version=3.3.1 Received: from bombadil.infradead.org (bombadil.infradead.org [65.50.211.133]) (using TLSv1.2 with cipher AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.wl.linuxfoundation.org (Postfix) with ESMTPS id 0C2B728EAC for ; Fri, 20 Oct 2017 07:26:35 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20170209; h=Sender: Content-Transfer-Encoding:Content-Type:MIME-Version:Cc:List-Subscribe: List-Help:List-Post:List-Archive:List-Unsubscribe:List-Id:References: In-Reply-To:Message-Id:Date:Subject:To:From:Reply-To:Content-ID: Content-Description:Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc :Resent-Message-ID:List-Owner; bh=kLRT9urKmcIYJTQUQbydWaVJw1VmaOzCHTGABEOpN3A=; b=IjRjVv6v8k8ikNdBc4lN6o2BV+ Y5xXLk2EKo7nQEFbeH/pc5CD++3+h5psRm6g2xyKjXaHd5WpDE7lzGMomXhqoAIwPVEtmUjMHM49Y f89c4xOCEnIEbHAK99Z8+53V/d6y0eHLbz5CEOw7mgeI5TsHQzKRRBCivATPK2TjpkszdeWjCeoRV dwXRv9Xi+vyKLhyO10bgcZTqKDJSY31T8n2vHv//moKVaRfqPk0RX9y8x/B5Ngou/4vRoihUg5XI3 cW8/rgvu61Co10ligXnMEDiXOF457y51fFwTdLzKzFr/jhlDzpjHUEvakjgv590m6f7MNuHwALttG 1Ya7URiA==; Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.87 #1 (Red Hat Linux)) id 1e5RhO-0007aU-AM; Fri, 20 Oct 2017 07:26:30 +0000 Received: from mga03.intel.com ([134.134.136.65]) by bombadil.infradead.org with esmtps (Exim 4.87 #1 (Red Hat Linux)) id 1e5Rfd-0004wm-Mv; Fri, 20 Oct 2017 07:24:46 +0000 Received: from fmsmga003.fm.intel.com ([10.253.24.29]) by orsmga103.jf.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 20 Oct 2017 00:24:21 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.43,405,1503385200"; d="scan'208";a="911830708" Received: from elena-thinkpad-x230.fi.intel.com ([10.237.72.87]) by FMSMGA003.fm.intel.com with ESMTP; 20 Oct 2017 00:24:15 -0700 From: Elena Reshetova To: davem@davemloft.net Subject: [PATCH 04/15] drivers, net, mlx4: convert mlx4_qp.refcount from atomic_t to refcount_t Date: Fri, 20 Oct 2017 10:23:38 +0300 Message-Id: <1508484229-19706-5-git-send-email-elena.reshetova@intel.com> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1508484229-19706-1-git-send-email-elena.reshetova@intel.com> References: <1508484229-19706-1-git-send-email-elena.reshetova@intel.com> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20171020_002442_460933_EACCCFBD X-CRM114-Status: UNSURE ( 9.54 ) X-CRM114-Notice: Please train this message. X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: peterz@infradead.org, matanb@mellanox.com, paulus@samba.org, zbr@ioremap.net, Elena Reshetova , nbd@openwrt.org, linux-rdma@vger.kernel.org, saeedm@mellanox.com, ganeshgr@chelsio.com, ajk@comnets.uni-bremen.de, keescook@chromium.org, sean.wang@mediatek.com, leonro@mellanox.com, linux-mediatek@lists.infradead.org, john@phrozen.org, matthias.bgg@gmail.com, linux-hams@vger.kernel.org, linux-arm-kernel@lists.infradead.org, netdev@vger.kernel.org, yishaih@mellanox.com, linux-kernel@vger.kernel.org, linux-ppp@vger.kernel.org, tariqt@mellanox.com MIME-Version: 1.0 Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org X-Virus-Scanned: ClamAV using ClamSMTP atomic_t variables are currently used to implement reference counters with the following properties: - counter is initialized to 1 using atomic_set() - a resource is freed upon counter reaching zero - once counter reaches zero, its further increments aren't allowed - counter schema uses basic atomic operations (set, inc, inc_not_zero, dec_and_test, etc.) Such atomic variables should be converted to a newly provided refcount_t type and API that prevents accidental counter overflows and underflows. This is important since overflows and underflows can lead to use-after-free situation and be exploitable. The variable mlx4_qp.refcount is used as pure reference counter. Convert it to refcount_t and fix up the operations. Suggested-by: Kees Cook Reviewed-by: David Windsor Reviewed-by: Hans Liljestrand Signed-off-by: Elena Reshetova --- drivers/net/ethernet/mellanox/mlx4/qp.c | 8 ++++---- include/linux/mlx4/device.h | 2 +- 2 files changed, 5 insertions(+), 5 deletions(-) diff --git a/drivers/net/ethernet/mellanox/mlx4/qp.c b/drivers/net/ethernet/mellanox/mlx4/qp.c index 2033209..769598f 100644 --- a/drivers/net/ethernet/mellanox/mlx4/qp.c +++ b/drivers/net/ethernet/mellanox/mlx4/qp.c @@ -55,7 +55,7 @@ void mlx4_qp_event(struct mlx4_dev *dev, u32 qpn, int event_type) qp = __mlx4_qp_lookup(dev, qpn); if (qp) - atomic_inc(&qp->refcount); + refcount_inc(&qp->refcount); spin_unlock(&qp_table->lock); @@ -66,7 +66,7 @@ void mlx4_qp_event(struct mlx4_dev *dev, u32 qpn, int event_type) qp->event(qp, event_type); - if (atomic_dec_and_test(&qp->refcount)) + if (refcount_dec_and_test(&qp->refcount)) complete(&qp->free); } @@ -420,7 +420,7 @@ int mlx4_qp_alloc(struct mlx4_dev *dev, int qpn, struct mlx4_qp *qp) if (err) goto err_icm; - atomic_set(&qp->refcount, 1); + refcount_set(&qp->refcount, 1); init_completion(&qp->free); return 0; @@ -520,7 +520,7 @@ EXPORT_SYMBOL_GPL(mlx4_qp_remove); void mlx4_qp_free(struct mlx4_dev *dev, struct mlx4_qp *qp) { - if (atomic_dec_and_test(&qp->refcount)) + if (refcount_dec_and_test(&qp->refcount)) complete(&qp->free); wait_for_completion(&qp->free); diff --git a/include/linux/mlx4/device.h b/include/linux/mlx4/device.h index daac2e3..b8e19c4 100644 --- a/include/linux/mlx4/device.h +++ b/include/linux/mlx4/device.h @@ -768,7 +768,7 @@ struct mlx4_qp { int qpn; - atomic_t refcount; + refcount_t refcount; struct completion free; u8 usage; };