From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail.linuxfoundation.org ([140.211.169.12]:52506 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752660AbbIKWl3 (ORCPT ); Fri, 11 Sep 2015 18:41:29 -0400 Subject: Patch "SCSI: Fix NULL pointer dereference in runtime PM" has been added to the 4.1-stable tree To: stern@rowland.harvard.edu, JBottomley@Odin.com, gregkh@linuxfoundation.org, ilanco@gmail.com, jthumshirn@suse.de, viraptor@gmail.com Cc: , From: Date: Fri, 11 Sep 2015 15:41:27 -0700 Message-ID: <144201128724464@kroah.com> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: stable-owner@vger.kernel.org List-ID: This is a note to let you know that I've just added the patch titled SCSI: Fix NULL pointer dereference in runtime PM to the 4.1-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: scsi-fix-null-pointer-dereference-in-runtime-pm.patch and it can be found in the queue-4.1 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let know about it. >>From 49718f0fb8c9af192b33d8af3a2826db04025371 Mon Sep 17 00:00:00 2001 From: Alan Stern Date: Mon, 17 Aug 2015 11:02:42 -0400 Subject: SCSI: Fix NULL pointer dereference in runtime PM MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit From: Alan Stern commit 49718f0fb8c9af192b33d8af3a2826db04025371 upstream. The routines in scsi_rpm.c assume that if a runtime-PM callback is invoked for a SCSI device, it can only mean that the device's driver has asked the block layer to handle the runtime power management (by calling blk_pm_runtime_init(), which among other things sets q->dev). However, this assumption turns out to be wrong for things like the ses driver. Normally ses devices are not allowed to do runtime PM, but userspace can override this setting. If this happens, the kernel gets a NULL pointer dereference when blk_post_runtime_resume() tries to use the uninitialized q->dev pointer. This patch fixes the problem by calling the block layer's runtime-PM routines only if the device's driver really does have a runtime-PM callback routine. Since ses doesn't define any such callbacks, the crash won't occur. This fixes Bugzilla #101371. Signed-off-by: Alan Stern Reported-by: Stanisław Pitucha Reported-by: Ilan Cohen Tested-by: Ilan Cohen Reviewed-by: Johannes Thumshirn Signed-off-by: James Bottomley Signed-off-by: Greg Kroah-Hartman --- drivers/scsi/scsi_pm.c | 22 +++++++++++----------- 1 file changed, 11 insertions(+), 11 deletions(-) --- a/drivers/scsi/scsi_pm.c +++ b/drivers/scsi/scsi_pm.c @@ -217,15 +217,15 @@ static int sdev_runtime_suspend(struct d { const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL; struct scsi_device *sdev = to_scsi_device(dev); - int err; + int err = 0; - err = blk_pre_runtime_suspend(sdev->request_queue); - if (err) - return err; - if (pm && pm->runtime_suspend) + if (pm && pm->runtime_suspend) { + err = blk_pre_runtime_suspend(sdev->request_queue); + if (err) + return err; err = pm->runtime_suspend(dev); - blk_post_runtime_suspend(sdev->request_queue, err); - + blk_post_runtime_suspend(sdev->request_queue, err); + } return err; } @@ -248,11 +248,11 @@ static int sdev_runtime_resume(struct de const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL; int err = 0; - blk_pre_runtime_resume(sdev->request_queue); - if (pm && pm->runtime_resume) + if (pm && pm->runtime_resume) { + blk_pre_runtime_resume(sdev->request_queue); err = pm->runtime_resume(dev); - blk_post_runtime_resume(sdev->request_queue, err); - + blk_post_runtime_resume(sdev->request_queue, err); + } return err; } Patches currently in stable-queue which might be from stern@rowland.harvard.edu are queue-4.1/scsi-fix-null-pointer-dereference-in-runtime-pm.patch