ps and /etc mode 775

[Chris Torek]

In article <32 at popeye.UUCP> sherm at popeye.UUCP (62545456-Paul A. Sherman;LZ 3E-303;6316) writes:
>Although /etc does not *need* to be 775 group sys, it makes ps(1) run
>much faster in most cases (see explanation below).  I don't know if 
>other standard programs make use of this situation, but I don't think 
>that it creates a security problem.

Someone else claims it does.  In any case, that

>... ps runs MUCH faster when it can use an existing ps_data

does not mean that you need keep /etc mode 775:

>If /etc is mode 755, owned by root, ps can only successfully create
>a new ps_data file when it is run by root. ... any user changing a
>password (with passwd) or login shell (with chsh) changes /etc/passwd
>and makes the older /etc/ps_data unusable.

[This seems rather silly: password and shell changes do not affect
the data ps needs.  I suppose it is an accident of the implementation.]

>Adding or removing nodes from /dev (which admittedly happens much
>less frequently and requires superuser permissions) also makes
>ps_data unusable since the modification time of /dev changes.  

[Adding or removing users probably makes ps_data unusable, too.]

A simple solution might be to run `ps >/dev/null' every hour or so from
cron.
-- 
In-Real-Life: Chris Torek, Univ of MD Comp Sci Dept (+1 301 454 7690)
UUCP:	seismo!umcp-cs!chris
CSNet:	chris at umcp-cs		ARPA:	chris at mimsy.umd.edu