From patchwork Fri Oct 20 07:23:39 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Reshetova, Elena" X-Patchwork-Id: 10019031 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 BBFB0602CB for ; Fri, 20 Oct 2017 07:26:59 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id ACE6A28EAF for ; Fri, 20 Oct 2017 07:26:59 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id A0B6728ECE; Fri, 20 Oct 2017 07:26:59 +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 24C4228EAF for ; Fri, 20 Oct 2017 07:26:59 +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=fRYeEUIsJ0VWBDSYEvnBXAOaIn6ZYM+8qcpWCT/30Y8=; b=EY88PApRXOpy6QrAYbLzgkiCeM h+1Bpyb5X9rKtQ1dzgf1ruaqlB0evjuK4GWo8Bq+Hznv/q89gXchJRSnq7734BQae163QLcgN4Ujw waog+gG785E5oFcYQfDf07/1GbtxzZZtZKEU0lPtq/+e5pBnYvfSEfZ0BUTuum5gmu889p43XvYyL 0QY4CLgmcnjSYCtykRQuiejiJX53s5m6heRIyNG3m8IEm1l8ZorVr5YVQ9J7wy4qroCQ+Q4r3oVk0 2J81JxKXyXSyQbo2yPeRxq/GyMH7DB41KS9QnJ+KDg2Ua6W/UQQL6t8CnUEJDPhFmpONTwz0jZBDF /KMt+N6g==; 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 1e5Rhi-0007ti-Ic; Fri, 20 Oct 2017 07:26:50 +0000 Received: from mga14.intel.com ([192.55.52.115]) by bombadil.infradead.org with esmtps (Exim 4.87 #1 (Red Hat Linux)) id 1e5Rfg-00051g-8i; Fri, 20 Oct 2017 07:24:46 +0000 Received: from fmsmga003.fm.intel.com ([10.253.24.29]) by fmsmga103.fm.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 20 Oct 2017 00:24:26 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.43,405,1503385200"; d="scan'208";a="911830722" Received: from elena-thinkpad-x230.fi.intel.com ([10.237.72.87]) by FMSMGA003.fm.intel.com with ESMTP; 20 Oct 2017 00:24:20 -0700 From: Elena Reshetova To: davem@davemloft.net Subject: [PATCH 05/15] drivers, net, mlx4: convert mlx4_srq.refcount from atomic_t to refcount_t Date: Fri, 20 Oct 2017 10:23:39 +0300 Message-Id: <1508484229-19706-6-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_002444_629645_91DEC053 X-CRM114-Status: UNSURE ( 9.91 ) 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_srq.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/srq.c | 8 ++++---- include/linux/mlx4/device.h | 2 +- 2 files changed, 5 insertions(+), 5 deletions(-) diff --git a/drivers/net/ethernet/mellanox/mlx4/srq.c b/drivers/net/ethernet/mellanox/mlx4/srq.c index bedf521..cbe4d97 100644 --- a/drivers/net/ethernet/mellanox/mlx4/srq.c +++ b/drivers/net/ethernet/mellanox/mlx4/srq.c @@ -49,7 +49,7 @@ void mlx4_srq_event(struct mlx4_dev *dev, u32 srqn, int event_type) srq = radix_tree_lookup(&srq_table->tree, srqn & (dev->caps.num_srqs - 1)); rcu_read_unlock(); if (srq) - atomic_inc(&srq->refcount); + refcount_inc(&srq->refcount); else { mlx4_warn(dev, "Async event for bogus SRQ %08x\n", srqn); return; @@ -57,7 +57,7 @@ void mlx4_srq_event(struct mlx4_dev *dev, u32 srqn, int event_type) srq->event(srq, event_type); - if (atomic_dec_and_test(&srq->refcount)) + if (refcount_dec_and_test(&srq->refcount)) complete(&srq->free); } @@ -203,7 +203,7 @@ int mlx4_srq_alloc(struct mlx4_dev *dev, u32 pdn, u32 cqn, u16 xrcd, if (err) goto err_radix; - atomic_set(&srq->refcount, 1); + refcount_set(&srq->refcount, 1); init_completion(&srq->free); return 0; @@ -232,7 +232,7 @@ void mlx4_srq_free(struct mlx4_dev *dev, struct mlx4_srq *srq) radix_tree_delete(&srq_table->tree, srq->srqn); spin_unlock_irq(&srq_table->lock); - if (atomic_dec_and_test(&srq->refcount)) + if (refcount_dec_and_test(&srq->refcount)) complete(&srq->free); wait_for_completion(&srq->free); diff --git a/include/linux/mlx4/device.h b/include/linux/mlx4/device.h index b8e19c4..a9b5fed 100644 --- a/include/linux/mlx4/device.h +++ b/include/linux/mlx4/device.h @@ -781,7 +781,7 @@ struct mlx4_srq { int max_gs; int wqe_shift; - atomic_t refcount; + refcount_t refcount; struct completion free; };