bgpd: Try fix extcommunity resource allocation probs, particularly with 'set extcom..'
* Extended communities has some kind of resource allocation problem which
causes a double-free if the 'set extcommunity ...' command is used.
Try fix by properly interning extcommunities.
Also, more generally, make unintern functions take a double pointer
so they can NULL out callers references - a usefully defensive programming
pattern for functions which make refs invalid.
Sadly, this patch doesn't fix the problem entirely - crashes still
occur on session clear.
* bgp_ecommunity.h: (ecommunity_{free,unintern}) take double pointer
args.
* bgp_community.h: (community_unintern) ditto
* bgp_attr.h: (bgp_attr_intern) ditto
* bgp_aspath.h: (bgp_aspath.h) ditto
* (general) update all callers of above
* bgp_routemap.c: (route_set_ecommunity_{rt,soo}) intern the new extcom added
to the attr, and unintern any old one.
(route_set_ecommunity_{rt,soo}_compile) intern the extcom to be used
for the route-map set.
(route_set_ecommunity_*_free) unintern to match, instead of free
(route_set_ecommunity_soo) Do as _rt does and don't just leak
any pre-existing community, add to it (is additive right though?)
diff --git a/bgpd/bgp_community.h b/bgpd/bgp_community.h
index bc1e56e..9e48377 100644
--- a/bgpd/bgp_community.h
+++ b/bgpd/bgp_community.h
@@ -57,7 +57,7 @@
extern struct community *community_uniq_sort (struct community *);
extern struct community *community_parse (u_int32_t *, u_short);
extern struct community *community_intern (struct community *);
-extern void community_unintern (struct community *);
+extern void community_unintern (struct community **);
extern char *community_str (struct community *);
extern unsigned int community_hash_make (struct community *);
extern struct community *community_str2com (const char *);