Nest: Fix race condition during reconfiguration, part 2 (470efcb9) · Commits · 戴 / Bird

If export filter is changed during reconfiguration and a route disappears between reconfiguration and refeed (e.g., if the route is a static route also removed during the reconfiguration), the route is not withdrawn. The issue was fixed for regular channels by an earlier patch. This patch fixes the issue for channels in RA_ACCEPTED mode (first-pass-the-filter), used by BGP with 'secondary' option.

nest/rt-table.c

+10 −0

Original line number	Diff line number	Diff line
		@@ -543,8 +543,18 @@ rt_notify_accepted(struct announce_hook ah, net net, rte new_changed, rte ol
		*
		* - We found new_best the same as new_changed, therefore it cannot
		* be old_best and we have to continue search for old_best.
		*
		* There is also a hack to ensure consistency in case of changed filters.
		* It does not find the proper old_best, just selects a non-NULL route.
		*/

		/* Hack for changed filters */
		if (old_changed && (old_changed->lastmod <= ah->last_out_filter_change))
		{
		old_best = old_changed;
		goto found;
		}

		/* First case */
		if (old_meet)
		if (old_best = export_filter(ah, old_changed, &old_free, NULL, 1))

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