Re: capable open_port() check wrong for kmem

[carbonated beverage <ramune@net-ronin.org>]

On Tue, Dec 10, 2002 at 12:33:04PM +0100, Olaf Dietsche wrote:
[snip]
> You may want to look at this thread:
> <http://groups.google.com/groups?threadm=87smza1p7f.fsf%40goat.bogus.local>

Hmm.

Okay, which approach is generally accpetible for inclusion into the kernel?
1) Nuke CAP_SYS_RAWIO check.  If the permissions on /dev/kmem is wrong,
tough.  It shouldn't be root:root 0666 in the first place anyways.
2) Add CAP_SYS_KMEM for read-only access, check for CAP_SYS_RAWIO for
the write case.
3) Special case /dev/kmem in open_port.

or:

4) Even if an application doesn't need write access to /dev/kmem, require
it to open /dev/kmem O_RDWR, as  it makes life easier for many people,
especially when modifying the kernel at run-time to hijack sysca... um, do
creative updates. :)

I'd prefer #1 or #2, but the discussion seems to have ended during the last
time the issue was brought up.

-- DN
Daniel