When you have multiple addresses on the same network on different
interfaces (such as when you are part of a carp pool), and you run
rpcbind -h to restrict which interfaces have rpc services, rpcbind can
none-the-less return addresses that aren't in the -h list. This patch
enforces the rule that when you specify -h on the command line, then
services returned from rpcbind must be to one of the addresses listed
in -h, or be a loopback address (since localhost is implicit when
running -h).
The root cause of this is the assumption in addrmerge that there can
be only one interface that matches a given network IP address. This
turns out not to be the case. To retain historical behavior, I didn't
try to fix the routine to prefer the address that the request came
into, since I didn't know the side effects that might cause in the
normal case. My quick analysis suggests that it wouldn't be a
problem, but since this code is tricky I opted for the more
conservative patch of only restricting the reply when -h is in effect.
Hence, this change will have no effect when you are running rpcbind
without -h.
Reviewed by: alfred@
Sponsored by: iX Systems
MFC after: 2 weeks