Commit a06044a4 authored by Nick Mathewson's avatar Nick Mathewson 🤹
Browse files

Check HT_REP_IS_BAD_() when giving a bug-7164 warning. 

This may let us know if we're hitting 7164 because of an
hte_hash-corruption situation proposed by "cypherpunks" in bug
11737.
parent 78301d99

changes/bug11737_diagnostic

0 → 100644
+5 −0
Original line number Diff line number Diff line 
  o Minor features (diagnostic):

    - When logging a warning because of bug #7164, additionally check the

      hash table for consistency (as proposed on ticket #11737). This may

      help diagnose bug #7164.

src/or/microdesc.c

+12 −6
Original line number Diff line number Diff line
@@ -386,18 +386,21 @@ microdesc_cache_clean(microdesc_cache_t *cache, time_t cutoff, int force) 
        smartlist_t *nodes = nodelist_find_nodes_with_microdesc(*mdp);

        const networkstatus_t *ns = networkstatus_get_latest_consensus();

        long networkstatus_age = -1;

        const int ht_badness = HT_REP_IS_BAD_(microdesc_map, &cache->map);

        if (ns) {

          networkstatus_age = now - ns->valid_after;

        }

        log_warn(LD_BUG, "Microdescriptor seemed very old "

                 "(last listed %d hours ago vs %d hour cutoff), but is still "

                 "marked as being held by %d node(s). I found %d node(s) "

                 "holding it. Current networkstatus is %ld hours old.",

                 "holding it. Current networkstatus is %ld hours old. "

                 "Hashtable badness is %d.",

                 (int)((now - (*mdp)->last_listed) / 3600),

                 (int)((now - cutoff) / 3600),

                 held_by_nodes,

                 smartlist_len(nodes),

                 networkstatus_age / 3600);

                 networkstatus_age / 3600,

                 ht_badness);



        SMARTLIST_FOREACH_BEGIN(nodes, const node_t *, node) {

          const char *rs_match = "No RS";
@@ -664,8 +667,10 @@ microdesc_free_(microdesc_t *md, const char *fname, int lineno) 
    tor_fragile_assert();

  }

  if (md->held_by_nodes) {

    microdesc_cache_t *cache = get_microdesc_cache();

    int found=0;

    const smartlist_t *nodes = nodelist_get_list();

    const int ht_badness = HT_REP_IS_BAD_(microdesc_map, &cache->map);

    SMARTLIST_FOREACH(nodes, node_t *, node, {

        if (node->md == md) {

          ++found;
@@ -674,12 +679,13 @@ microdesc_free_(microdesc_t *md, const char *fname, int lineno) 
      });

    if (found) {

      log_warn(LD_BUG, "microdesc_free() called from %s:%d, but md was still "

               "referenced %d node(s); held_by_nodes == %u",

               fname, lineno, found, md->held_by_nodes);

               "referenced %d node(s); held_by_nodes == %u, ht_badness == %d",

               fname, lineno, found, md->held_by_nodes, ht_badness);

    } else {

      log_warn(LD_BUG, "microdesc_free() called from %s:%d with held_by_nodes "

               "set to %u, but md was not referenced by any nodes",

               fname, lineno, md->held_by_nodes);

               "set to %u, but md was not referenced by any nodes. "

               "ht_badness == %d",

               fname, lineno, md->held_by_nodes, ht_badness);

    }

    tor_fragile_assert();

  }