Strange syntax in /etc/netgroup causes core dump +SOLUTION

[Bigbrother]

Because other people may have similar problems, I report the problem and
solution to this list.

Recently I upgrade one of my networks to use YP/NIS format.
----
matrix# uname -a
FreeBSD matrix.XXXXXXX 4.7-RELEASE-p10 
----

In one machine I had a netgroup of


---
cat /etc/netgroup
matrix (,,)
---
---
cat /etc/passwd
+ at matrix:*:::::/sbin/nologin
---
Because I didn't want anybody to login to that server.

This caused a lot of programs that read the passwd file to SEGFAULT with
signal 11, and some others to core dump (like 'top', 'repquota' and
others) on the offending machine.

The solution was to remove the (,,) from the entry corresponding to that
machine in /etc/netgroup
And to change it to 
---
cat /etc/netgroup
matrix
---

>From that time I have no problem and everything works fine. I don't know
if it is a bug or not, but the problem of core dumps without any warning
made me searching and debbuging a lot of hours. Perhaps a minor bug fix
should happen on the ypbind code, so applications that read the passwd
file not to core dump when they find entries like that in netgroup
files.


Best Regards,

BB