Messages in this thread | | | Date | Tue, 25 Jan 2011 09:28:41 -0800 | From | Kees Cook <> | Subject | Re: RFC: introduce "K" flag for printf, similar to %pK |
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Hi Joe,
On Mon, Jan 24, 2011 at 06:17:04PM -0800, Joe Perches wrote: > On Mon, 2011-01-24 at 18:03 -0800, Kees Cook wrote: > > In the interests of hiding kernel addresses from userspace (without > > messing with file permissions), I want to use %pK for /proc/kallsyms and > > /proc/modules, but this results in changing several %x's to %p's. The > > primary side-effects is that some legitimately "0" value things in > > /proc/kallsyms turn into "(null)". > > Another option would be to allow '0' for > kernel pointers.
But then this changes the behavior of %p where (null) is expected. (i.e. when switching from %p to %pK.)
I'm personally fine with that, as I suspect anything parsing the output that can handle finding "(null)" will be fine with "0" too. But the other way around, not so much. :)
-Kees
-- Kees Cook Ubuntu Security Team
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