Re: Security Hole?

Andrew Mileski (dmtech@magi.com)
Mon, 4 Mar 1996 10:19:18 -0500 (EST)

>On Sun, 3 Mar 1996, Andrew Mileski wrote:
>> I've noticed that the linux kernel allows anyone to freely
>> request/release IRQ, DMA, and I/O. Is this a security
>> hole, or am I missing something that only allows root to
>> do these things?
>
>*gasp*
>
>What do you mean? all these register_irq and such functions are kernel
>internal functions that can only be used by device drivers and such.
>And these are indeed required to know what they do.
>
>There is actually a syscall (well, 2 actually) for user programs
>to get access to i/o ports. (if they try otherwise they'll get killed
>with a segfault). And yes, the userprogram must run as root to use these
>syscalls.
>
>I must admit that I don't get the point of your mail.

Thanks for the info. the point of my mail was to learn what
you just explained - I'm no kernel expert, hence I asked
for the experts :-)

A patch for a new resource management system (now includes
address space management and subset requests/releases) is
available at http://www.magi.com/~dmtech/pnp/pnp-patch.1.gz

I'll submit it to Linus (or someone...) when I feel all the
i's are dotted and the t's are crossed.

-- Andrew E. Mileski --

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