Fix valgrind error when marking a descriptor as never-downloadable.

When we got a descriptor that we (as an authority) rejected as totally
bad, we were freeing it, then using the digest in its RAM to look up its
download status.  Caught by arma with valgrind.  Bugfix on 0.2.1.9-alpha.

diff --git a/ChangeLog b/ChangeLog
index 05d5719465430075a50b8fb7ec96aeb6cdbed7df..b84da4ceebb86239dacdd367ba6751b9a12de0a5 100644 (file)
--- a/ChangeLog
+++ b/ChangeLog
@@ -21,6 +21,8 @@ Changes in version 0.2.1.15??? - ????-??-??
     - Stop using malloc_usable_size() to use more area than we had
       actually allocated: it was safe, but made valgrind really
       unhappy.  Bugfix on 0.2.0.x.
+    - Fix use of freed memory when deciding to mark a non-addable
+      descriptor as never-downloadable.  Bugfix on 0.2.1.9-alpha.
 
 
 Changes in version 0.2.1.14-rc - 2009-04-12

diff --git a/src/or/routerlist.c b/src/or/routerlist.c
index c6bfca4546a95885a37c35ec79fad07d2d6bc668..de38e354e0d4c52a6edb1c7011cc2a85fe1a0c96 100644 (file)
--- a/src/or/routerlist.c
+++ b/src/or/routerlist.c
@@ -3513,6 +3513,7 @@ router_load_routers_from_string(const char *s, const char *eos,
 
   SMARTLIST_FOREACH_BEGIN(routers, routerinfo_t *, ri) {
     was_router_added_t r;
+    char d[DIGEST_LEN];
     if (requested_fingerprints) {
       base16_encode(fp, sizeof(fp), descriptor_digests ?
                       ri->cache_info.signed_descriptor_digest :
@@ -3533,6 +3534,7 @@ router_load_routers_from_string(const char *s, const char *eos,
       }
     }
 
+    memcpy(d, ri->cache_info.signed_descriptor_digest, DIGEST_LEN);
     r = router_add_to_routerlist(ri, &msg, from_cache, !from_cache);
     if (WRA_WAS_ADDED(r)) {
       any_changed++;
@@ -3541,11 +3543,10 @@ router_load_routers_from_string(const char *s, const char *eos,
       smartlist_clear(changed);
     } else if (WRA_WAS_REJECTED(r)) {
       download_status_t *dl_status;
-      dl_status = router_get_dl_status_by_descriptor_digest(
-          ri->cache_info.signed_descriptor_digest);
+      dl_status = router_get_dl_status_by_descriptor_digest(d);
       if (dl_status) {
         log_info(LD_GENERAL, "Marking router %s as never downloadable",
-                 hex_str(ri->cache_info.signed_descriptor_digest, DIGEST_LEN));
+                 hex_str(d, DIGEST_LEN));
         download_status_mark_impossible(dl_status);
       }
     }