Re: Kernel Oops during usb usage (2.6.5)

[Bill Davidsen <davidsen@tmr.com>]

Greg KH wrote:
> On Fri, Apr 23, 2004 at 10:56:17PM +0200, E. Oltmanns wrote:
> 
>>Hello everyone,
>>
>>Summary:
>>Kernel Oops caused by multiple access requests to a single scanner
>>through libusb.
>>
>>Detailed description:
>>The following script leads to an kernel oops on my System:
>>#!/bin/bash
>>scanimage > test &
>>scanimage -h
>>
>>This is because scanimage -h tries to append a list of availlable
>>scanners to the help output and thus interferes with the first
>>scanimage process which is initializing the scanner at the same
>>moment.
> 
> 
> Heh, then don't do that :)
> 
> Accesses by two different processes of the same device through usbfs is
> big trouble.  Don't do that.
> 
> That being said, I have some usbfs locking patches that might help a bit
> here that will probably show up in the next -mm release if you want to
> see if that helps you out or not.

Just in general, if there is anything a non-root user can do to crash 
the system, it's probably a kernel bug by definition. It doesn't matter 
that's it a stupid thing to do, it might be malicious. And in this case 
it might just be user error.

Glad someone is working on locking, bozos and evil-doers abound ;-)

-- 
    -bill davidsen (davidsen@tmr.com)
"The secret to procrastination is to put things off until the
  last possible moment - but no longer"  -me