K 10
svn:author
V 2
bz
K 8
svn:date
V 27
2020-11-25T20:58:01.183306Z
K 7
svn:log
V 743
IPv6: set ifdisabled in the kernel rather than in rc

Enable ND6_IFF_IFDISABLED when the interface is created in the
kernel before return to user space.

This avoids a race when an interface is create by a program which
also calls ifconfig IF inet6 -ifdisabled and races with the
devd -> /etc/pccard_ether -> .. netif start IF -> ifdisabled
calls (the devd/rc framework disabling IPv6 again after the program
had enabled it already).

In case the global net.inet6.ip6.accept_rtadv was turned on,
we also default to enabling IPv6 on the interfaces, rather than
disabling them.

PR:		248172
Reported by:	Gert Doering (gert greenie.muc.de)
Reviewed by:	glebius (, phk)
MFC after:	2 weeks
Differential Revision:	https://reviews.freebsd.org/D27324

END