From patchwork Thu Jan 7 19:38:28 2010 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jan Kiszka X-Patchwork-Id: 43533 X-Patchwork-Delegate: davem@davemloft.net Return-Path: X-Original-To: patchwork-incoming@ozlabs.org Delivered-To: patchwork-incoming@ozlabs.org Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id E4448B7C48 for ; Sat, 23 Jan 2010 10:24:55 +1100 (EST) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754336Ab0AVXYc (ORCPT ); Fri, 22 Jan 2010 18:24:32 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1755881Ab0AVXYT (ORCPT ); Fri, 22 Jan 2010 18:24:19 -0500 Received: from fmmailgate03.web.de ([217.72.192.234]:60623 "EHLO fmmailgate03.web.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755240Ab0AVXYE (ORCPT ); Fri, 22 Jan 2010 18:24:04 -0500 Received: from smtp07.web.de (fmsmtp07.dlan.cinetic.de [172.20.5.215]) by fmmailgate03.web.de (Postfix) with ESMTP id 5F6C513C783EA; Sat, 23 Jan 2010 00:24:03 +0100 (CET) Received: from [92.75.141.69] (helo=[192.168.1.10]) by smtp07.web.de with asmtp (TLSv1:AES256-SHA:256) (WEB.DE 4.110 #314) id 1NYSrD-0006zB-00; Sat, 23 Jan 2010 00:24:03 +0100 Message-Id: <3be6c33ad163b72ee4e6821eae582a6fb50003e9.1264201407.git.jan.kiszka@web.de> In-Reply-To: References: From: Jan Kiszka To: David Miller , Karsten Keil Cc: linux-kernel@vger.kernel.org, i4ldeveloper@listserv.isdn4linux.de, isdn4linux@listserv.isdn4linux.de, netdev@vger.kernel.org Date: Thu, 7 Jan 2010 20:38:28 +0100 Subject: [PATCH 17/31] CAPI: Fix racy capi_read X-Sender: jan.kiszka@web.de X-Provags-ID: V01U2FsdGVkX18WbhZ4Xjc1DTm09C3PtMh8VfIKZsteLc0nns8J k9wN5AP+hEH5HqVcsBbsUegwnIdtNkG+esXA35KA2m/fCX9Zt2 7hKE1mV74= Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org capi_read still used interruptible_sleep_on, risking to miss a wakeup this way. Convert it to wait_event_interruptible. Signed-off-by: Jan Kiszka --- drivers/isdn/capi/capi.c | 19 +++++++------------ 1 files changed, 7 insertions(+), 12 deletions(-) diff --git a/drivers/isdn/capi/capi.c b/drivers/isdn/capi/capi.c index b71b8b1..90a20fa 100644 --- a/drivers/isdn/capi/capi.c +++ b/drivers/isdn/capi/capi.c @@ -656,24 +656,19 @@ capi_read(struct file *file, char __user *buf, size_t count, loff_t *ppos) struct capidev *cdev = (struct capidev *)file->private_data; struct sk_buff *skb; size_t copied; + int err; if (!cdev->ap.applid) return -ENODEV; - if ((skb = skb_dequeue(&cdev->recvqueue)) == NULL) { - + skb = skb_dequeue(&cdev->recvqueue); + if (!skb) { if (file->f_flags & O_NONBLOCK) return -EAGAIN; - - for (;;) { - interruptible_sleep_on(&cdev->recvwait); - if ((skb = skb_dequeue(&cdev->recvqueue)) != NULL) - break; - if (signal_pending(current)) - break; - } - if (skb == NULL) - return -ERESTARTNOHAND; + err = wait_event_interruptible(cdev->recvwait, + (skb = skb_dequeue(&cdev->recvqueue))); + if (err) + return err; } if (skb->len > count) { skb_queue_head(&cdev->recvqueue, skb);