Messages in this thread | | | Subject | Re: [PATCH] capability: WARN when invalid capability is requested rather than BUG/panic | From | Eric Paris <> | Date | Tue, 30 Sep 2008 13:22:30 -0400 |
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On Tue, 2008-09-30 at 11:28 -0500, Serge E. Hallyn wrote: > Quoting Eric Paris (eparis@redhat.com):
> > > Perhaps we should have CAP_TO_INDEX mask itself? > > > > > > #define CAP_TO_INDEX(x) (((x) >> 5) & _KERNEL_CAPABILITY_U32S) > > > > Well, you save a branch and won't get the pagefault so it does 'fix' the > > pagefault/panic from cap code. It doesn't tell us when others screw up > > and SELinux is still possibly going to BUG(). We are also going to > > actually be returning a permission decision not on what was requested > > but on something wholely different. > > So exactly what was requested?
A capability that they cannot possibly have since it doesn't exist :)
> > I like mine better, but I'm ok with yours and can just do my changes in > > SELinux if this is how cap wants to handle it. I don't really like the > > Heh I don't like either one, just thought this would reduce the overhead > a bit :)
No argument from me that patching up for buggy drivers sucks. Yours would be less overhead, and it would return the cap system back to pre-2.6.25 operation (garbage in garbage out but no panic). Since we already have the branch in SELinux its no 'extra' overhead to EPERM there instead of here (garbage in EPERM out).
-Eric
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