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Re: /dev/ksyms permissions



Maxime Villard <max%M00nBSD.net@localhost> writes:

> So, making /dev/ksyms 440 root:kmem should not break anything.
>
> If it does, then there's a bug in the offending tool in the first place.

Agreed.  systat is one of them.  It takes care to call kvm_openfiles()
while setgid kmem, but kvm_openfiles() doesn't open /dev/ksyms,
expecting that the other kvm functions can do that at need.  So when
e.g. 'systat vmstat' calls kvm_nlist() after privileges have been
dropped, it fails:

systat: nlist: can't find following symbols:
 _intrnames
 _eintrnames
 _intrcnt
 _eintrcnt
 _allevents

-tih
-- 
Most people who graduate with CS degrees don't understand the significance
of Lisp.  Lisp is the most important idea in computer science.  --Alan Kay

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