From patchwork Fri Oct 20 07:23:45 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Reshetova, Elena" X-Patchwork-Id: 10019115 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 CB43960224 for ; Fri, 20 Oct 2017 07:42:25 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id BCCCF28DFE for ; Fri, 20 Oct 2017 07:42:25 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id B125628EC7; Fri, 20 Oct 2017 07:42:25 +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 8C2B328DFE for ; Fri, 20 Oct 2017 07:42:24 +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=tvV+LWHmz3kIXX2CxuN/v11QbJCDPhSRSJKWn7CmNZ4=; b=YAkN96o5c74xMNQT5EQOI2XK1r mTqR/A7o6CL9H5EP+R/5K0EA+OH8MMsAOKDyb0/HckRC81dR76tV1NAqsAH1dxuRV8e0jmUiIqlDo 2Xkdvn8hWiy6ed34LF+ejtIi2Q05JrFP7fiAqgsmhviiarOfsnhvTxgKOUGQkm0VGcYHSvaggpzw+ FKAASWoTeGO09ycYGKRny+RpDNFeo6PXaITXkcJjQRgc+PNxLNkY/4Cv5qJU85yWOqL/e/BtINFq0 w6+DykSXJTBwo+K/LadgJqDsqN5NXb6D3dBOPKckrTK4ARYGcD8XRDsxpXKYZ3I5BgSlNSJv4dAMj N/BvF++w==; 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 1e5Rwm-00049Z-3C; Fri, 20 Oct 2017 07:42:24 +0000 Received: from casper.infradead.org ([2001:8b0:10b:1236::1]) by bombadil.infradead.org with esmtps (Exim 4.87 #1 (Red Hat Linux)) id 1e5Ruu-0000qf-Ma; Fri, 20 Oct 2017 07:40:28 +0000 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=casper.20170209; h=References:In-Reply-To:Message-Id:Date: Subject:Cc:To:From:Sender:Reply-To:MIME-Version:Content-Type: Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Id: List-Help:List-Unsubscribe:List-Subscribe:List-Post:List-Owner:List-Archive; bh=EKpco3ZHTaozuTq50YMHzCPloD0xD0DmVfxC9GsMYgw=; b=COFypeD8CHKhZKg1dHq1KlRGW WSG/jujuJTIvleMIkaYLvOm3LoyZRlboFuWD3WA1M8vqSY9+kNQUbSWn0L544Wa3mep2m/3yUBqVl 2DLAe2QQuWBsXrJVLhK+3+RP+rSVSNodL5x5dHUvitiFHTa8DIYWke47heXlllveK9ZqODqhErHPd PYyOQJbm4GPeBfZUpiVPX+G8Om23RYEUtY7cF/BixvY+fvp++vOrppV9vYjHBIdtDg8sUs73f7niN upC2POaxXK9S+lXFaAHrWYhzS6pZAT//OFp3PV9LdNUSOugtlK6mW+9NOB9uZSaNP/wTbDcHR6zNW 76/255k4Q==; Received: from mga03.intel.com ([134.134.136.65]) by casper.infradead.org with esmtps (Exim 4.87 #1 (Red Hat Linux)) id 1e5Rgb-0005la-GJ; Fri, 20 Oct 2017 07:25:43 +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 00:25:12 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.43,405,1503385200"; d="scan'208";a="911830978" Received: from elena-thinkpad-x230.fi.intel.com ([10.237.72.87]) by FMSMGA003.fm.intel.com with ESMTP; 20 Oct 2017 00:24:56 -0700 From: Elena Reshetova To: davem@davemloft.net Subject: [PATCH 11/15] drivers, net: convert masces_tx_sa.refcnt from atomic_t to refcount_t Date: Fri, 20 Oct 2017 10:23:45 +0300 Message-Id: <1508484229-19706-12-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_082541_883410_EBD2292A X-CRM114-Status: GOOD ( 13.58 ) 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 masces_tx_sa.refcnt 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/macsec.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) diff --git a/drivers/net/macsec.c b/drivers/net/macsec.c index e0aeb51..8948b6a 100644 --- a/drivers/net/macsec.c +++ b/drivers/net/macsec.c @@ -188,7 +188,7 @@ struct macsec_tx_sa { struct macsec_key key; spinlock_t lock; u32 next_pn; - atomic_t refcnt; + refcount_t refcnt; bool active; struct macsec_tx_sa_stats __percpu *stats; struct rcu_head rcu; @@ -362,7 +362,7 @@ static struct macsec_tx_sa *macsec_txsa_get(struct macsec_tx_sa __rcu *ptr) if (!sa || !sa->active) return NULL; - if (!atomic_inc_not_zero(&sa->refcnt)) + if (!refcount_inc_not_zero(&sa->refcnt)) return NULL; return sa; @@ -379,7 +379,7 @@ static void free_txsa(struct rcu_head *head) static void macsec_txsa_put(struct macsec_tx_sa *sa) { - if (atomic_dec_and_test(&sa->refcnt)) + if (refcount_dec_and_test(&sa->refcnt)) call_rcu(&sa->rcu, free_txsa); } @@ -1437,7 +1437,7 @@ static int init_tx_sa(struct macsec_tx_sa *tx_sa, char *sak, int key_len, } tx_sa->active = false; - atomic_set(&tx_sa->refcnt, 1); + refcount_set(&tx_sa->refcnt, 1); spin_lock_init(&tx_sa->lock); return 0;