bin/54513: ifconfig exits on newly created carp interfaces

[kardel%netbsd.org@localhost]

>Number:         54513
>Category:       bin
>Synopsis:       fconfig exits on newly created carp interfaces
>Confidential:   no
>Severity:       serious
>Priority:       medium
>Responsible:    bin-bug-people
>State:          open
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Fri Aug 30 19:20:00 +0000 2019
>Originator:     Frank Kardel
>Release:        NetBSD 9.99.6
>Organization:
	
>Environment:
	
	
System: NetBSD pip 9.99.6 NetBSD 9.99.6 (PIPGEN) #20: Sat Aug 10 12:14:12 CEST 2019 kardel@pip:.../src/obj.amd64/sys/arch/amd64/compile/PIPGEN amd64
Architecture: x86_64
Machine: amd64
>Description:
	Create a carp interface instance and see ifconfig exit with following error:
# ifconfig
...
carp0: flags=0x8802<BROADCAST,SIMPLEX,MULTICAST> mtu 1500
ifconfig: print_link_addresses: ioctl: Can't assign requested address
[ exit 1 here ]

	This also appears in 9.0_BETA.

	Things are fine once the carp device is fully initialized.
	ifconfig shouldn't exit on newly created carp devices.

>How-To-Repeat:
	# ifconfig carp0 create
	# ifconfig carp1 create
	# ifconfig

	See that carp1 is never listed. It will be listed when
	you ifconfig carp0 destroy.

>Fix:
	Don't exit in the print_link_addresses function on a failed ioctl(2).

>Unformatted: