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Date: Tue, 2 Aug 2011 11:54:47 +0300
From: Dan Carpenter <error27@gmail.com>
To: linux-kernel@vger.kernel.org
Cc: Tino Keitel <tino.keitel@tikei.de>, Florian Mickler <florian@mickler.org>,
        mchehab@infradead.org
Subject: Re: USB related "unable to handle kernel paging request" in 3.0.0-rc7
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Looking at this, I noticed a memory corruption bug introduce in:
ab22cbda6651d "[media] vp7045: get rid of on-stack dma buffers"

vp7045_properties.size_of_priv is sizeof(u8 *) so in vp7045_usb_probe()
the d->priv buffer gets allocated twice.  Once in:
	dvb_usb_device_init()
	-> dvb_usb_init()

And once explicitly to a larger buffer later on in the function with
a kmalloc().

So the two places that use the buffer will probably race and cause
memory corruption.

regards,
dan carpenter