cache: hold a reference to the cache ops while a cache is provided over it

Signed-off-by: Thomas Graf <tgraf@suug.ch>

diff --git a/lib/cache_mngt.c b/lib/cache_mngt.c
index d5ca6d3c9857036bffc9c4f082a776a2f1c41f2b..8f011fbf167a980c37f29df732ce2f2e9d43c1ce 100644 (file)
--- a/lib/cache_mngt.c
+++ b/lib/cache_mngt.c
@@ -335,6 +335,14 @@ void nl_cache_mngt_provide(struct nl_cache *cache)
                BUG();
        else {
                nl_cache_get(cache);
+
+               /*
+                * Hold a reference to the cache operations to ensure the
+                * ops don't go away while we use it to store the cache pointer.
+                */
+               if (!ops->co_major_cache)
+                       nl_cache_ops_get(ops);
+
                ops->co_major_cache = cache;
        }
 
@@ -360,6 +368,7 @@ void nl_cache_mngt_unprovide(struct nl_cache *cache)
                BUG();
        else if (ops->co_major_cache == cache) {
                nl_cache_free(ops->co_major_cache);
+               nl_cache_ops_put(ops);
                ops->co_major_cache = NULL;
        }
 
@@ -369,12 +378,15 @@ void nl_cache_mngt_unprovide(struct nl_cache *cache)
 struct nl_cache *__nl_cache_mngt_require(const char *name)
 {
        struct nl_cache_ops *ops;
+       struct nl_cache *cache = NULL;
 
-       ops = nl_cache_ops_lookup(name);
-       if (ops)
-               return ops->co_major_cache;
+       ops = nl_cache_ops_lookup_safe(name);
+       if (ops) {
+               cache = ops->co_major_cache;
+               nl_cache_ops_put(ops);
+       }
        
-       return NULL;
+       return cache;
 }
 
 /**