From: Ondrej Zajicek (work) Date: Wed, 30 Jan 2019 16:03:30 +0000 (+0100) Subject: Nest: Prevent withdraws from propagation back to source protocol X-Git-Tag: v1.6.6~5 X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=b4438e40efa498325f38f0bf4681ecb2bbba4da7;p=thirdparty%2Fbird.git Nest: Prevent withdraws from propagation back to source protocol The earlier fix loosen conditions for not running filters on old route when deciding about route propagation to a protocol to avoid issues with ghost routes in some race conditions. Unfortunately, the fix also caused back-propagation of withdraws. For regular updates, back-propagation is prevented in import_control hooks, but these are not called on withdraws. For them, import_control hooks are called on old routes instead, changing (old, NULL) notification to (NULL, NULL), which is ignored. By not calling export processing in some cases, the withdraw is not ignored and is back-propagated. This patch fixes that by contract conditions so the earlier fix is not applied to back-propagated updates. --- diff --git a/nest/rt-table.c b/nest/rt-table.c index cae6afaad..a06b8c35c 100644 --- a/nest/rt-table.c +++ b/nest/rt-table.c @@ -434,7 +434,8 @@ rt_notify_basic(struct announce_hook *ah, net *net, rte *new0, rte *old0, int re if (new) new = export_filter(ah, new, &new_free, &tmpa, 0); - if (old && !(refeed || (old->lastmod <= ah->last_out_filter_change))) + if (old && !(refeed || ((old->lastmod <= ah->last_out_filter_change) && + (p != old->sender->proto)))) old = export_filter(ah, old, &old_free, NULL, 1); if (!new && !old)