From patchwork Tue Mar 28 08:56:40 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Reshetova, Elena" X-Patchwork-Id: 9648555 X-Patchwork-Delegate: kvalo@adurom.com 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 25EA5601E9 for ; Tue, 28 Mar 2017 09:06:59 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 1916A1FF28 for ; Tue, 28 Mar 2017 09:06:59 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 0DC5C1FF87; Tue, 28 Mar 2017 09:06:59 +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=-6.3 required=2.0 tests=BAYES_00,DKIM_SIGNED, RCVD_IN_DNSWL_HI, RCVD_IN_SORBS_SPAM, T_DKIM_INVALID autolearn=unavailable version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 8862A20855 for ; Tue, 28 Mar 2017 09:06:57 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932099AbdC1JFz (ORCPT ); Tue, 28 Mar 2017 05:05:55 -0400 Received: from mga02.intel.com ([134.134.136.20]:57640 "EHLO mga02.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754782AbdC1I63 (ORCPT ); Tue, 28 Mar 2017 04:58:29 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=simple/simple; d=intel.com; i=@intel.com; q=dns/txt; s=intel; t=1490691508; x=1522227508; h=from:to:cc:subject:date:message-id:in-reply-to: references; bh=IOnLsyIUPg6lwyz51M82kIMQyiyGLjJkE4EiL3zNfl4=; b=s89r6FhOVkylSDAUoPsm1HRt8ziWCkHICI9D53DvzWflRqXW7RpmOBrQ w3GNYpXYXKSdSk76iyPF0htNPkGz/w==; Received: from fmsmga006.fm.intel.com ([10.253.24.20]) by orsmga101.jf.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 28 Mar 2017 01:58:23 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.36,236,1486454400"; d="scan'208";a="81798243" Received: from unknown (HELO elena-ThinkPad-X230.ger.corp.intel.com) ([10.249.44.56]) by fmsmga006.fm.intel.com with ESMTP; 28 Mar 2017 01:58:16 -0700 From: Elena Reshetova To: netdev@vger.kernel.org Cc: linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-rdma@vger.kernel.org, linux-hams@vger.kernel.org, linux-ppp@vger.kernel.org, linux-wireless@vger.kernel.org, ganeshgr@chelsio.com, nbd@openwrt.org, blogic@openwrt.org, matthias.bgg@gmail.com, yishaih@mellanox.com, saeedm@mellanox.com, matanb@mellanox.com, leonro@mellanox.com, ajk@comnets.uni-bremen.de, paulus@samba.org, j@w1.fi, kvalo@codeaurora.org, peterz@infradead.org, keescook@chromium.org, gregkh@linuxfoundation.org, Elena Reshetova , Hans Liljestrand , David Windsor Subject: [PATCH 13/16] drivers, net, ppp: convert ppp_file.refcnt from atomic_t to refcount_t Date: Tue, 28 Mar 2017 11:56:40 +0300 Message-Id: <1490691403-4016-14-git-send-email-elena.reshetova@intel.com> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1490691403-4016-1-git-send-email-elena.reshetova@intel.com> References: <1490691403-4016-1-git-send-email-elena.reshetova@intel.com> Sender: linux-wireless-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-wireless@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP refcount_t type and corresponding API should be used instead of atomic_t when the variable is used as a reference counter. This allows to avoid accidental refcounter overflows that might lead to use-after-free situations. Signed-off-by: Elena Reshetova Signed-off-by: Hans Liljestrand Signed-off-by: Kees Cook Signed-off-by: David Windsor --- drivers/net/ppp/ppp_generic.c | 17 +++++++++-------- 1 file changed, 9 insertions(+), 8 deletions(-) diff --git a/drivers/net/ppp/ppp_generic.c b/drivers/net/ppp/ppp_generic.c index f9c0e62..7b1352c 100644 --- a/drivers/net/ppp/ppp_generic.c +++ b/drivers/net/ppp/ppp_generic.c @@ -51,6 +51,7 @@ #include #include #include +#include #include #include @@ -84,7 +85,7 @@ struct ppp_file { struct sk_buff_head xq; /* pppd transmit queue */ struct sk_buff_head rq; /* receive queue for pppd */ wait_queue_head_t rwait; /* for poll on reading /dev/ppp */ - atomic_t refcnt; /* # refs (incl /dev/ppp attached) */ + refcount_t refcnt; /* # refs (incl /dev/ppp attached) */ int hdrlen; /* space to leave for headers */ int index; /* interface unit / channel number */ int dead; /* unit/channel has been shut down */ @@ -407,7 +408,7 @@ static int ppp_release(struct inode *unused, struct file *file) unregister_netdevice(ppp->dev); rtnl_unlock(); } - if (atomic_dec_and_test(&pf->refcnt)) { + if (refcount_dec_and_test(&pf->refcnt)) { switch (pf->kind) { case INTERFACE: ppp_destroy_interface(PF_TO_PPP(pf)); @@ -880,7 +881,7 @@ static int ppp_unattached_ioctl(struct net *net, struct ppp_file *pf, mutex_lock(&pn->all_ppp_mutex); ppp = ppp_find_unit(pn, unit); if (ppp) { - atomic_inc(&ppp->file.refcnt); + refcount_inc(&ppp->file.refcnt); file->private_data = &ppp->file; err = 0; } @@ -895,7 +896,7 @@ static int ppp_unattached_ioctl(struct net *net, struct ppp_file *pf, spin_lock_bh(&pn->all_channels_lock); chan = ppp_find_channel(pn, unit); if (chan) { - atomic_inc(&chan->file.refcnt); + refcount_inc(&chan->file.refcnt); file->private_data = &chan->file; err = 0; } @@ -2641,7 +2642,7 @@ ppp_unregister_channel(struct ppp_channel *chan) pch->file.dead = 1; wake_up_interruptible(&pch->file.rwait); - if (atomic_dec_and_test(&pch->file.refcnt)) + if (refcount_dec_and_test(&pch->file.refcnt)) ppp_destroy_channel(pch); } @@ -3011,7 +3012,7 @@ init_ppp_file(struct ppp_file *pf, int kind) pf->kind = kind; skb_queue_head_init(&pf->xq); skb_queue_head_init(&pf->rq); - atomic_set(&pf->refcnt, 1); + refcount_set(&pf->refcnt, 1); init_waitqueue_head(&pf->rwait); } @@ -3128,7 +3129,7 @@ ppp_connect_channel(struct channel *pch, int unit) list_add_tail(&pch->clist, &ppp->channels); ++ppp->n_channels; pch->ppp = ppp; - atomic_inc(&ppp->file.refcnt); + refcount_inc(&ppp->file.refcnt); ppp_unlock(ppp); ret = 0; @@ -3159,7 +3160,7 @@ ppp_disconnect_channel(struct channel *pch) if (--ppp->n_channels == 0) wake_up_interruptible(&ppp->file.rwait); ppp_unlock(ppp); - if (atomic_dec_and_test(&ppp->file.refcnt)) + if (refcount_dec_and_test(&ppp->file.refcnt)) ppp_destroy_interface(ppp); err = 0; }