[PATCH v6 resend 03/10] server: Ensure completion_callback is called before async is destroyed.

[Jinoh Kang]

async_set_result() is the only way the async completion callback can be
called.  If the async were never queued (e.g. if it is a request async,
and it failed in a very early stage), it could be destroyed without its
completion callback ever being called.  This leads to memory leak.

Fix this by calling the completion_callback if it was not already called
and then set to NULL.

Signed-off-by: Jinoh Kang <jinoh.kang.kr at gmail.com>
---

Notes:
    v4 -> v5: new patch
    v5 -> v6: no changes

 server/async.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/server/async.c b/server/async.c
index d49fb8b7c04..3e5ca7ccf8c 100644
--- a/server/async.c
+++ b/server/async.c
@@ -144,6 +144,10 @@ static void async_destroy( struct object *obj )
     struct async *async = (struct async *)obj;
     assert( obj->ops == &async_ops );
 
+    if (async->completion_callback)
+        async->completion_callback( async->completion_callback_private );
+    async->completion_callback = NULL;
+
     list_remove( &async->process_entry );
 
     if (async->queue)
-- 
2.34.1