From patchwork Mon Feb 8 20:12:21 2010 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jan Kiszka X-Patchwork-Id: 44841 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 C8B8DB7CF5 for ; Tue, 9 Feb 2010 07:20:11 +1100 (EST) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755207Ab0BHUTT (ORCPT ); Mon, 8 Feb 2010 15:19:19 -0500 Received: from fmmailgate01.web.de ([217.72.192.221]:37099 "EHLO fmmailgate01.web.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754837Ab0BHUNG (ORCPT ); Mon, 8 Feb 2010 15:13:06 -0500 Received: from smtp05.web.de (fmsmtp05.dlan.cinetic.de [172.20.4.166]) by fmmailgate01.web.de (Postfix) with ESMTP id 733B01465EEAA; Mon, 8 Feb 2010 21:13:05 +0100 (CET) Received: from [88.65.45.120] (helo=localhost.localdomain) by smtp05.web.de with asmtp (TLSv1:AES256-SHA:256) (WEB.DE 4.110 #314) id 1NeZyj-0006fo-01; Mon, 08 Feb 2010 21:13:05 +0100 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, Alan Cox , Marcel Holtmann Subject: [PATCH v2 17/41] CAPI: Fix racy capi_read Date: Mon, 8 Feb 2010 21:12:21 +0100 Message-Id: <342ae07a02d368f2d76821f980c0118b55518f04.1265659935.git.jan.kiszka@web.de> X-Mailer: git-send-email 1.6.0.2 In-Reply-To: References: In-Reply-To: References: X-Sender: jan.kiszka@web.de X-Provags-ID: V01U2FsdGVkX1/Wnf16tfmIrDwkiPuAgPENBWJx6VzkDfNDHsAL Ka/Q5VhUM/g+dnzNo9muPCabx9r9rm4MrE0CsEhyj9KPzR4KC6 XczRtFp4o= 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 f8f8660..8abec96 100644 --- a/drivers/isdn/capi/capi.c +++ b/drivers/isdn/capi/capi.c @@ -657,24 +657,19 @@ 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);