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_ecommunity.h b/bgpd/bgp_ecommunity.h
index 942fdc7..2f59dc4 100644
--- a/bgpd/bgp_ecommunity.h
+++ b/bgpd/bgp_ecommunity.h
@@ -67,13 +67,13 @@
extern void ecommunity_init (void);
extern void ecommunity_finish (void);
-extern void ecommunity_free (struct ecommunity *);
+extern void ecommunity_free (struct ecommunity **);
extern struct ecommunity *ecommunity_parse (u_int8_t *, u_short);
extern struct ecommunity *ecommunity_dup (struct ecommunity *);
extern struct ecommunity *ecommunity_merge (struct ecommunity *, struct ecommunity *);
extern struct ecommunity *ecommunity_intern (struct ecommunity *);
extern int ecommunity_cmp (const void *, const void *);
-extern void ecommunity_unintern (struct ecommunity *);
+extern void ecommunity_unintern (struct ecommunity **);
extern unsigned int ecommunity_hash_make (void *);
extern struct ecommunity *ecommunity_str2com (const char *, int, int);
extern char *ecommunity_ecom2str (struct ecommunity *, int);