what is the usage of /usr/lib/perf/libperfstat_updt_dictionary in AIX and the relation with command topas?

Question

Currently I have encountered the same problem as below link:

http://www.aixmind.com/?tag=usrlibperflibperfstat_updt_dictionary

I have solved the same problem, but I want to know the reason.

What is the usage of /usr/lib/perf/libperfstat_updt_dictionary?

And why when I set the setuid bit to this file, I can run topas in non-root user? What is the relation between the file and topas?

Thanks all.

Updated: 1. Actually, I want to know the usage of /usr/lib/perf/libperfstat_updt_dictionary 2. And the relation between command topas and this file.

Answer 1

/usr/lib/perf/libperfstat_updt_dictionary is an executable. If the setuid bit is set, then it gains the privileges of the owner of the file (which is root in this case). See setuid for more information. With the effective user of root, it can do anything it wants to. This opens holes that can be exploited which are explained in the "Security" section of the referenced page.

It creates /usr/lib/perf/libperfstat_dictionary.dat which appears to me to be stats only for disks and then topas uses that.

As far as "usage"... I would not call it directly. Its not a "user" type program but more something hidden in the background used by topas and perftools. argc and argv are not used. Its a one trick pony.