From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753454Ab2BEW0L (ORCPT ); Sun, 5 Feb 2012 17:26:11 -0500 Received: from 1wt.eu ([62.212.114.60]:61796 "EHLO 1wt.eu" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753228Ab2BEW0F (ORCPT ); Sun, 5 Feb 2012 17:26:05 -0500 Message-Id: <20120205220949.833935474@pcw.home.local> User-Agent: quilt/0.48-1 Date: Sun, 05 Feb 2012 23:09:58 +0100 From: Willy Tarreau To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Chris Ball , Greg KH Subject: [PATCH 09/91] mmc: sdhci: Check mrq != NULL in sdhci_tasklet_finish In-Reply-To: <0635750f5f06ed2ca212b91fcb5c4483@local> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 2.6.27-longterm review patch. If anyone has any objections, please let us know. ------------------ 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 files changed, 7 insertions(+), 0 deletions(-) Index: longterm-2.6.27/drivers/mmc/host/sdhci.c =================================================================== --- longterm-2.6.27.orig/drivers/mmc/host/sdhci.c 2012-02-05 22:34:36.053916156 +0100 +++ longterm-2.6.27/drivers/mmc/host/sdhci.c 2012-02-05 22:34:36.192916064 +0100 @@ -1165,6 +1165,13 @@ 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);