Re: PROBLEM: Kernel Oops on cat /proc/ioports

[Andrew Morton]

Berend De Schouwer wrote:
> 
> [1.] One line summary of the problem:
> 
> Running "cat /proc/ioports" causes a segfault and kernel oops.
> 
> ...
> [7.3.] Module information (from /proc/modules):
> 
> cyclades              147616  16 (autoclean)

cyclades does request_region(), but forgets to do release_region().
This will leave the region allocated in kernel data structures,
but its "name" field resides in module memory.

So if you load cyclades.o, then rmmod it, then cat /proc/ioports,
you'll touch unmapped memory and go boom.

Some brave soul needs to teach cyclades about release_region().
Shame the Nobel prizes are all gone this year.

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