The patch below does not apply to the 3.11-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <[email protected]>.

thanks,

greg k-h

------------------ original commit in Linus's tree ------------------

>From 2e923a0527ac439e135b9961e58d3acd876bba10 Mon Sep 17 00:00:00 2001
From: Alexey Khoroshilov <[email protected]>
Date: Wed, 3 Jul 2013 16:17:34 -0300
Subject: [PATCH] [media] hdpvr: fix iteration over uninitialized lists in
 hdpvr_probe()

free_buff_list and rec_buff_list are initialized in the middle of hdpvr_probe(),
but if something bad happens before that, error handling code calls 
hdpvr_delete(),
which contains iteration over the lists (via hdpvr_free_buffers()).
The patch moves the lists initialization to the beginning and by the way fixes
goto label in error handling of registering videodev.
Found by Linux Driver Verification project (linuxtesting.org).

Signed-off-by: Alexey Khoroshilov <[email protected]>
Signed-off-by: Hans Verkuil <[email protected]>
Signed-off-by: Mauro Carvalho Chehab <[email protected]>
Cc: [email protected]

diff --git a/drivers/media/usb/hdpvr/hdpvr-core.c 
b/drivers/media/usb/hdpvr/hdpvr-core.c
index cb694055..6e507077 100644
--- a/drivers/media/usb/hdpvr/hdpvr-core.c
+++ b/drivers/media/usb/hdpvr/hdpvr-core.c
@@ -303,6 +303,11 @@ static int hdpvr_probe(struct usb_interface *interface,
 
        dev->workqueue = 0;
 
+       /* init video transfer queues first of all */
+       /* to prevent oops in hdpvr_delete() on error paths */
+       INIT_LIST_HEAD(&dev->free_buff_list);
+       INIT_LIST_HEAD(&dev->rec_buff_list);
+
        /* register v4l2_device early so it can be used for printks */
        if (v4l2_device_register(&interface->dev, &dev->v4l2_dev)) {
                dev_err(&interface->dev, "v4l2_device_register failed\n");
@@ -325,10 +330,6 @@ static int hdpvr_probe(struct usb_interface *interface,
        if (!dev->workqueue)
                goto error;
 
-       /* init video transfer queues */
-       INIT_LIST_HEAD(&dev->free_buff_list);
-       INIT_LIST_HEAD(&dev->rec_buff_list);
-
        dev->options = hdpvr_default_options;
 
        if (default_video_input < HDPVR_VIDEO_INPUTS)
@@ -405,7 +406,7 @@ static int hdpvr_probe(struct usb_interface *interface,
                                    video_nr[atomic_inc_return(&dev_nr)]);
        if (retval < 0) {
                v4l2_err(&dev->v4l2_dev, "registering videodev failed\n");
-               goto error;
+               goto reg_fail;
        }
 
        /* let the user know what node this device is now attached to */

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