@@ -217,15 +217,15 @@ static int sdev_runtime_suspend(struct device *dev)
{
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 device *dev)
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;
}
This is a note to let you know that I have just added a patch titled SCSI: Fix NULL pointer dereference in runtime PM to the linux-3.19.y-queue branch of the 3.19.y-ckt extended stable tree which can be found at: http://kernel.ubuntu.com/git/ubuntu/linux.git/log/?h=linux-3.19.y-queue This patch is scheduled to be released in version 3.19.8-ckt7. If you, or anyone else, feels it should not be added to this tree, please reply to this email. For more information about the 3.19.y-ckt tree, see https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable Thanks. -Kamal ------ From 82abd4c49d84c4687cb237d2cbcb3c07b90f147d Mon Sep 17 00:00:00 2001 From: Alan Stern <stern@rowland.harvard.edu> 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 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 <stern@rowland.harvard.edu> Reported-by: Stanisław Pitucha <viraptor@gmail.com> Reported-by: Ilan Cohen <ilanco@gmail.com> Tested-by: Ilan Cohen <ilanco@gmail.com> Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de> Signed-off-by: James Bottomley <JBottomley@Odin.com> Signed-off-by: Kamal Mostafa <kamal@canonical.com> --- drivers/scsi/scsi_pm.c | 22 +++++++++++----------- 1 file changed, 11 insertions(+), 11 deletions(-) -- 1.9.1