Re: [PATCH] USB: add USB test and measurement class driver
From: Alan Stern
Date: Wed Aug 27 2008 - 12:06:49 EST
On Wed, 27 Aug 2008, Oliver Neukum wrote:
> This is a race condition.
>
> CPU A CPU B
> open()
> usb_find_interface()
> disconnect()
> kref_put()
> usbtmc_delete()
> kfree()
> kref_get()
>
> You can write to free memory. You must use a static mutex for
> mutual exclusion between open() and disconnect()
Is that necessary? usbcore includes its own mutual exclusion now.
Look in file.c at how minor_rwsem is used.
Alan Stern
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/