bin/102143: yppush: remove async i/o and add proper error handling

[Thomas Quinot]

>Number:         102143
>Category:       bin
>Synopsis:       yppush: remove async i/o and add proper error handling
>Confidential:   no
>Severity:       serious
>Priority:       medium
>Responsible:    freebsd-bugs
>State:          open
>Quarter:        
>Keywords:       
>Date-Required:
>Class:          sw-bug
>Submitter-Id:   current-users
>Arrival-Date:   Wed Aug 16 12:50:20 GMT 2006
>Closed-Date:
>Last-Modified:
>Originator:     Thomas Quinot
>Release:        FreeBSD 6.1-RC i386
>Organization:
>Environment:
System: FreeBSD melamine.cuivre.fr.eu.org 6.1-RC FreeBSD 6.1-RC #0: Thu May 4 13:21:21 CEST 2006 thomas at melamine.cuivre.fr.eu.org:/space/build/obj/space/build/src/RELENG_6/sys/MELAMINE i386


	
>Description:
	YPPush currently uses asynchronous (SIGIO-based) input/output,
	and makes call to the memory allocator during handling of SIGIO,
	which can cause an abort due to incorrect reentrant invocation
	of free(3), as described here:
	http://lists.freebsd.org/pipermail/freebsd-net/2004-October/005321.html

	It also misses error handling:
	* for an incoming response with an incorrect tid;
	* for a failure to register the response RPC program,

	and has incorrect error handling for failure to allocate a job
	descriptor (this should be handled prior to registering the transient
	program, otherwise yppush_exit can't unregister it in case of malloc failure).

>How-To-Repeat:
	
>Fix:
	A patch for the first item (SIGIO issues) has been posted for review
	on freebsd-net:
	http://lists.freebsd.org/pipermail/freebsd-net/2006-August/011309.html
	where no objection was raised.

	Consequently, I'll commit it together with minor changes adding the
	missing error handlers and fixing the incorrect one.

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