Re: Registration Weakness in Linux Kernel's Bin ary formats

From: Alan Cox
Date: Tue Oct 03 2006 - 18:29:28 EST


Ar Maw, 2006-10-03 am 16:48 -0500, ysgrifennodd Chase Venters:
> So the problem you find is that newly registered binfmts are inserted into
> the front of the binfmt list instead of the rear, and this means that a
> binfmt handler can slip in at runtime at run quietly before any other
> handler?

This is a feature as anyone trying to debug versions of the elf loader
could would find out quite fast.

>
> I'm not sure I see this as a real problem. If you can load a module into
> kernel space and access arbitrary symbols (not to mention run in ring 0) I
> think you can do a lot more than just hide out on the binfmt list.
>
> Am I missing something?

Don't think so. At the point you can load code into the kernel you can
replace any code anyway.

NOTABUG

Alan

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