Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754992Ab1EFARz (ORCPT ); Thu, 5 May 2011 20:17:55 -0400 Received: from kroah.org ([198.145.64.141]:32867 "EHLO coco.kroah.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754664Ab1EFANZ (ORCPT ); Thu, 5 May 2011 20:13:25 -0400 X-Mailbox-Line: From gregkh@clark.kroah.org Thu May 5 17:12:09 2011 Message-Id: <20110506001209.055756635@clark.kroah.org> User-Agent: quilt/0.48-16.4 Date: Thu, 05 May 2011 17:10:50 -0700 From: Greg KH To: linux-kernel@vger.kernel.org, stable@kernel.org Cc: stable-review@kernel.org, torvalds@linux-foundation.org, akpm@linux-foundation.org, alan@lxorguk.ukuu.org.uk, Chris Ball Subject: [patch 18/38] mmc: sdhci: Check mrq != NULL in sdhci_tasklet_finish In-Reply-To: <20110506001225.GA10547@kroah.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1350 Lines: 45 2.6.38-stable review patch. If anyone has any objections, please let us know. ------------------ From: Chris Ball commit 0c9c99a765321104cc5f9c97f949382a9ba4927e upstream. It seems that under certain circumstances the sdhci_tasklet_finish() call can be entered with mrq set to NULL, causing the system to crash with a NULL pointer de-reference. Seen on S3C6410 system. Based on a patch by Dimitris Papastamos. Reported-by: Dimitris Papastamos Signed-off-by: Chris Ball Signed-off-by: Greg Kroah-Hartman --- drivers/mmc/host/sdhci.c | 7 +++++++ 1 file changed, 7 insertions(+) --- a/drivers/mmc/host/sdhci.c +++ b/drivers/mmc/host/sdhci.c @@ -1334,6 +1334,13 @@ static void sdhci_tasklet_finish(unsigne host = (struct sdhci_host*)param; + /* + * If this tasklet gets rescheduled while running, it will + * be run again afterwards but without any active request. + */ + if (!host->mrq) + return; + spin_lock_irqsave(&host->lock, flags); del_timer(&host->timer); -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/