[tor-commits] [tor/master] Always check returns from tor_munmap_file() in microdesc.c

[nickm at torproject.org]

commit df076eccfaa680ee08b8ae866690d9a2a8ba5555
Author: Andrea Shepard <andrea at torproject.org>
Date:   Tue Mar 18 12:39:02 2014 -0700

    Always check returns from tor_munmap_file() in microdesc.c
---
 src/or/microdesc.c  |   20 ++++++++++++++++----
 src/or/routerlist.c |   22 ++++++++--------------
 2 files changed, 24 insertions(+), 18 deletions(-)

diff --git a/src/or/microdesc.c b/src/or/microdesc.c
index 6419ea7..f196536 100644
--- a/src/or/microdesc.c
+++ b/src/or/microdesc.c
@@ -275,6 +275,7 @@ void
 microdesc_cache_clear(microdesc_cache_t *cache)
 {
   microdesc_t **entry, **next;
+
   for (entry = HT_START(microdesc_map, &cache->map); entry; entry = next) {
     microdesc_t *md = *entry;
     next = HT_NEXT_RMV(microdesc_map, &cache->map, entry);
@@ -283,7 +284,13 @@ microdesc_cache_clear(microdesc_cache_t *cache)
   }
   HT_CLEAR(microdesc_map, &cache->map);
   if (cache->cache_content) {
-    tor_munmap_file(cache->cache_content);
+    int res = tor_munmap_file(cache->cache_content);
+    if (res != 0) {
+      log_warn(LD_FS,
+               "tor_munmap_file() failed clearing microdesc cache; "
+               "we are probably about to leak memory.");
+      /* TODO something smarter? */
+    }
     cache->cache_content = NULL;
   }
   cache->total_len_seen = 0;
@@ -429,7 +436,7 @@ int
 microdesc_cache_rebuild(microdesc_cache_t *cache, int force)
 {
   open_file_t *open_file;
-  int fd = -1;
+  int fd = -1, res;
   microdesc_t **mdp;
   smartlist_t *wrote;
   ssize_t size;
@@ -496,8 +503,13 @@ microdesc_cache_rebuild(microdesc_cache_t *cache, int force)
 
   /* We must do this unmap _before_ we call finish_writing_to_file(), or
    * windows will not actually replace the file. */
-  if (cache->cache_content)
-    tor_munmap_file(cache->cache_content);
+  if (cache->cache_content) {
+    res = tor_munmap_file(cache->cache_content);
+    if (res != 0) {
+      log_warn(LD_FS,
+               "Failed to unmap old microdescriptor cache while rebuilding");
+    }
+  }
 
   if (finish_writing_to_file(open_file) < 0) {
     log_warn(LD_DIR, "Error rebuilding microdescriptor cache: %s",
diff --git a/src/or/routerlist.c b/src/or/routerlist.c
index 725718b..c96fb2c 100644
--- a/src/or/routerlist.c
+++ b/src/or/routerlist.c
@@ -990,7 +990,6 @@ router_rebuild_store(int flags, desc_store_t *store)
   size_t total_expected_len = 0;
   int had_any;
   int force = flags & RRS_FORCE;
-  int res;
 
   if (!force && !router_should_rebuild_store(store)) {
     r = 0;
@@ -1065,10 +1064,9 @@ router_rebuild_store(int flags, desc_store_t *store)
 
   /* Our mmap is now invalid. */
   if (store->mmap) {
-    res = tor_munmap_file(store->mmap);
-    if (res == 0) {
-      store->mmap = NULL;
-    } else {
+    int res = tor_munmap_file(store->mmap);
+    store->mmap = NULL;
+    if (res != 0) {
       log_warn(LD_FS, "Unable to munmap route store in %s", fname);
     }
   }
@@ -1141,16 +1139,14 @@ router_reload_router_list_impl(desc_store_t *store)
   struct stat st;
   int extrainfo = (store->type == EXTRAINFO_STORE);
   store->journal_len = store->store_len = 0;
-  int res;
 
   fname = get_datadir_fname(store->fname_base);
 
   if (store->mmap) {
     /* get rid of it first */
-    res = tor_munmap_file(store->mmap);
-    if (res == 0) {
-      store->mmap = NULL;
-    } else {
+    int res = tor_munmap_file(store->mmap);
+    store->mmap = NULL;
+    if (res != 0) {
       log_warn(LD_FS, "Failed to munmap %s", fname);
       tor_free(fname);
       return -1;
@@ -2796,8 +2792,6 @@ extrainfo_free_(void *e)
 void
 routerlist_free(routerlist_t *rl)
 {
-  int res;
-
   if (!rl)
     return;
   rimap_free(rl->identity_map, NULL);
@@ -2811,13 +2805,13 @@ routerlist_free(routerlist_t *rl)
   smartlist_free(rl->routers);
   smartlist_free(rl->old_routers);
   if (routerlist->desc_store.mmap) {
-    res = tor_munmap_file(routerlist->desc_store.mmap);
+    int res = tor_munmap_file(routerlist->desc_store.mmap);
     if (res != 0) {
       log_warn(LD_FS, "Failed to munmap routerlist->desc_store.mmap");
     }
   }
   if (routerlist->extrainfo_store.mmap) {
-    res = tor_munmap_file(routerlist->extrainfo_store.mmap);
+    int res = tor_munmap_file(routerlist->extrainfo_store.mmap);
     if (res != 0) {
       log_warn(LD_FS, "Failed to munmap routerlist->extrainfo_store.mmap");
     }