On Fri, 2011-02-25 at 11:16 -0800, David Miller wrote:

From: Ben Hutchings <redacted>
Date: Fri, 25 Feb 2011 19:07:59 +0000

quoted

You realise that module loading doesn't actually run in the context of
request_module(), right?

Why is that a barrier?  We could simply pass a capability mask into
request_module if necessary.

It's an implementation detail, and not a deterrant to my suggested
scheme.

It's not an implementation detail.  modprobe currently runs with full
capabilities; your proposal requires its capabilities to be limited to
those of the capabilities of the process that triggered the
request_module() (plus, presumably, CAP_SYS_MODULE).

Now modprobe doesn't have CAP_DAC_OVERRIDE and can't read modprobe
configuration files that belong to users other than root.

It doesn't have CAP_SYS_MKNOD so it can't run hooks that call mknod.

etc.

Ben.

-- 
Ben Hutchings, Senior Software Engineer, Solarflare Communications
Not speaking for my employer; that's the marketing department's job.
They asked us to note that Solarflare product names are trademarked.