bin/136073: recent nscd changes cause client processes to die with SIGPIPE

[Andrew Stevenson]

>Number:         136073
>Category:       bin
>Synopsis:       recent nscd changes cause client processes to die with SIGPIPE
>Confidential:   no
>Severity:       serious
>Priority:       high
>Responsible:    freebsd-bugs
>State:          open
>Quarter:        
>Keywords:       
>Date-Required:
>Class:          sw-bug
>Submitter-Id:   current-users
>Arrival-Date:   Fri Jun 26 17:30:01 UTC 2009
>Closed-Date:
>Last-Modified:
>Originator:     Andrew Stevenson
>Release:        FreeBSD 7.2-STABLE i386
>Organization:
UgH!
>Environment:
System: FreeBSD anu.hursley.ibm.com 7.2-STABLE FreeBSD 7.2-STABLE #14: Thu Jun 25 12:28:57 BST 2009 root at anu.hursley.ibm.com:/usr/obj/usr/src/sys/ANU i386


	
>Description:

After upgrading to stable as of 2 days ago I have found that processes
trying to fetch password data frequently die with SIGPIPE. My
nsswitch.conf contains:

passwd: files cache ldap
group: files cache ldap

Removing cache makes the problem go away, as does reverting to nscd from
7.2-RELEASE. If I run nscd -nst (nscd from stable) it logs the error:

E3 from on_mp_write_session_write_response_write1: write failed

when the problem occurs. I had a quick look at the code but didn't
understand the structure well enough to know what it was supposed to be
doing. I have 2 ldap servers configured both using ldaps.

This prevented me from logging into the machine after the upgrade though
I had console access so could recover.

>How-To-Repeat:

Any password checking process seems to suffer - e.g. try to log on from
the console or via XDM or su from an existing shell. Oddly ssh, even
when using passwords seems unaffected. I used "logins" to do most of my
testing.

>Fix:

Work around is to revert to nscd from 7.2-RELEASE or to change
nsswitch.conf to not use cache.

>Release-Note:
>Audit-Trail:
>Unformatted: