From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932590AbdCFOhR (ORCPT ); Mon, 6 Mar 2017 09:37:17 -0500 Received: from mga04.intel.com ([192.55.52.120]:16772 "EHLO mga04.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932516AbdCFOhB (ORCPT ); Mon, 6 Mar 2017 09:37:01 -0500 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.35,254,1484035200"; d="scan'208";a="72746358" From: Elena Reshetova To: gregkh@linuxfoundation.org Cc: linux-kernel@vger.kernel.org, xen-devel@lists.xenproject.org, netdev@vger.kernel.org, linux1394-devel@lists.sourceforge.net, linux-bcache@vger.kernel.org, linux-raid@vger.kernel.org, linux-media@vger.kernel.org, devel@linuxdriverproject.org, linux-pci@vger.kernel.org, linux-s390@vger.kernel.org, fcoe-devel@open-fcoe.org, linux-scsi@vger.kernel.org, open-iscsi@googlegroups.com, devel@driverdev.osuosl.org, target-devel@vger.kernel.org, linux-serial@vger.kernel.org, linux-usb@vger.kernel.org, peterz@infradead.org, Elena Reshetova , Hans Liljestrand , Kees Cook , David Windsor Subject: [PATCH 19/29] drivers, s390: convert lcs_reply.refcnt from atomic_t to refcount_t Date: Mon, 6 Mar 2017 16:21:06 +0200 Message-Id: <1488810076-3754-20-git-send-email-elena.reshetova@intel.com> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1488810076-3754-1-git-send-email-elena.reshetova@intel.com> References: <1488810076-3754-1-git-send-email-elena.reshetova@intel.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 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/s390/net/lcs.c | 8 +++----- drivers/s390/net/lcs.h | 3 ++- 2 files changed, 5 insertions(+), 6 deletions(-) diff --git a/drivers/s390/net/lcs.c b/drivers/s390/net/lcs.c index 211b31d..18dc787 100644 --- a/drivers/s390/net/lcs.c +++ b/drivers/s390/net/lcs.c @@ -774,15 +774,13 @@ lcs_get_lancmd(struct lcs_card *card, int count) static void lcs_get_reply(struct lcs_reply *reply) { - WARN_ON(atomic_read(&reply->refcnt) <= 0); - atomic_inc(&reply->refcnt); + refcount_inc(&reply->refcnt); } static void lcs_put_reply(struct lcs_reply *reply) { - WARN_ON(atomic_read(&reply->refcnt) <= 0); - if (atomic_dec_and_test(&reply->refcnt)) { + if (refcount_dec_and_test(&reply->refcnt)) { kfree(reply); } @@ -798,7 +796,7 @@ lcs_alloc_reply(struct lcs_cmd *cmd) reply = kzalloc(sizeof(struct lcs_reply), GFP_ATOMIC); if (!reply) return NULL; - atomic_set(&reply->refcnt,1); + refcount_set(&reply->refcnt,1); reply->sequence_no = cmd->sequence_no; reply->received = 0; reply->rc = 0; diff --git a/drivers/s390/net/lcs.h b/drivers/s390/net/lcs.h index 150fcb4..3802f4f 100644 --- a/drivers/s390/net/lcs.h +++ b/drivers/s390/net/lcs.h @@ -4,6 +4,7 @@ #include #include #include +#include #include #define LCS_DBF_TEXT(level, name, text) \ @@ -270,7 +271,7 @@ struct lcs_buffer { struct lcs_reply { struct list_head list; __u16 sequence_no; - atomic_t refcnt; + refcount_t refcnt; /* Callback for completion notification. */ void (*callback)(struct lcs_card *, struct lcs_cmd *); wait_queue_head_t wait_q; -- 2.7.4