Pull up following revision(s) (requested by ozaki-r in ticket #407):
sys/compat/linux32/common/linux32_socket.c: revision 1.28
sys/net/if.c: revision 1.400
sys/netipsec/key.c: revision 1.243
sys/compat/linux/common/linux_socket.c: revision 1.139
sys/netinet/ip_carp.c: revision 1.93
sys/netinet6/in6.c: revision 1.252
sys/netinet6/in6.c: revision 1.253
sys/netinet6/in6.c: revision 1.254
sys/net/if_spppsubr.c: revision 1.173
sys/net/if_spppsubr.c: revision 1.174
sys/compat/common/uipc_syscalls_40.c: revision 1.14
Protect IFADDR_READER_FOREACH and obtained ifa with psz/psref
Fix usage of FOREACH macro
key_sad.lock is held there so SAVLIST_WRITER_FOREACH is enough.
Protect IFADDR_READER_FOREACH and obtained ifa with psz/psref
Protect IFADDR_READER_FOREACH and obtained ifa with psz/psref (more)
Fix and make consistent of usages of psz/psref in ifconf variants
Remove unnecessary goto because there is no cleanup code to share (NFC)
Tweak a condition; we don't need to care ifacount to be negative
Fix a race condition of in6_ifinit
in6_ifinit checks the number of IPv6 addresses on a given interface and
if it's zero (i.e., an IPv6 address being assigned to the interface
is the first one), call if_addr_init. However, the actual assignment of
the address (ifa_insert) is out of in6_ifinit. The check and the
assignment must be done atomically.
Fix it by holding in6_ifaddr_lock during in6_ifinit and ifa_insert.
And also add missing pserialize to IFADDR_READER_FOREACH.

(martin)