Re: Odd root (and suid root) behavior

Marek Michalkiewicz (marekm@i17linuxb.ists.pwr.wroc.pl)
Wed, 15 May 1996 03:59:12 +0200 (MET DST)


Steven N. Hirsch:
> As of (at least) 1.99.2, an initial root login (or su root) after
> system startup hangs for almost a minute on a 486DX4-100 machine. Once
> logged in, though, everything procedes normally!

Hi,

I noticed this too, and I think I tracked it down - it seems to hang
in syslog() (root logins are logged). Perhaps the large number of
boot up messages confuses syslogd somehow (and /dev/log is a stream
socket, so I guess writes block if data is not read quickly enough).
It doesnt't seem to depend on verions of kernel/libc/syslogd (happens
on 1.2.13/4.6.27/1.2 as well as 1.3.100/5.2.18/1.3) except that
I think it didn't happen on one very old machine (syslogd <1.2?).

> This (mis)behavior also applies to the first suid root program run as a
> conventional user after login, if this helps.

Perhaps that program happens to use syslog() too, like su?

> I am running shadow passwords if that makes a difference. Sorry not be

That shouldn't make much difference except that shadow does more logging
and may make the problem show up more frequently.

Any ideas how to fix it?

Marek