netlink: Always process all responses to a netlink request

A single netlink request can result in multiple response datagrams.  We
process multiple response datagrams in some circumstances, but there are
cases where we exit early and will leave remaining datagrams in the queue.
These will be flushed in nl_send() before we send another request.

This is confusing, and not what we need to reliably check for errors from
netlink operations.  So, instead, make sure we always process all the
response datagrams whenever we send a request (excepting fatal errors).

In most cases this is just a matter of avoiding early exits from nl_foreach
loops.  nl_route_dup() is a bit trickier, because we need to retain all the
routes we're going to try to copy in a single buffer.  Here we instead use
a secondary buffer to flush any remaining datagrams, and report an error
if there are any additional routes in those datagrams .

Link: https://bugs.passt.top/show_bug.cgi?id=67
Link: https://bugs.passt.top/show_bug.cgi?id=60
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Stefano Brivio <sbrivio@redhat.com>

0 files changed, 0 insertions, 0 deletions