Fix bug 5334

I did not test with a zero length file :-)
(This used to be commit 7d7a73944c2dcf078f7bc8de65d575f32f9aa851)

3 files changed, 45 insertions, 0 deletions

diff --git a/source3/include/async_req.h b/source3/include/async_req.h
index 6df53602b26..fb463d5b9a1 100644
--- a/source3/include/async_req.h
+++ b/source3/include/async_req.h
@@ -75,6 +75,13 @@ void async_req_done(struct async_req *req);
 void async_req_error(struct async_req *req, NTSTATUS status);
 
 /*
+ * If a request is finished or ends in error even before it has the chance to
+ * trigger the event loop, post a status. This creates an immediate timed
+ * event to call the async function if there is any.
+ */
+bool async_post_status(struct async_req *req, NTSTATUS status);
+
+/*
  * Convenience helper to easily check alloc failure within a callback.
  *
  * Call pattern would be
diff --git a/source3/lib/async_req.c b/source3/lib/async_req.c
index 01154ca4363..2e85d9a38d7 100644
--- a/source3/lib/async_req.c
+++ b/source3/lib/async_req.c
@@ -58,6 +58,36 @@ void async_req_error(struct async_req *req, NTSTATUS status)
 	}
 }
 
+static void async_trigger(struct event_context *ev, struct timed_event *te,
+			  const struct timeval *now, void *priv)
+{
+	struct async_req *req = talloc_get_type_abort(priv, struct async_req);
+
+	TALLOC_FREE(te);
+	if (NT_STATUS_IS_OK(req->status)) {
+		async_req_done(req);
+	}
+	else {
+		async_req_error(req, req->status);
+	}
+}
+
+bool async_post_status(struct async_req *req, NTSTATUS status)
+{
+	/*
+	 * Used if a request is finished before it even started
+	 */
+
+	req->status = status;
+
+	if (event_add_timed(req->event_ctx, req, timeval_zero(),
+			    "async_trigger",
+			    async_trigger, req) == NULL) {
+		return false;
+	}
+	return true;
+}
+
 bool async_req_nomem(const void *p, struct async_req *req)
 {
 	if (p != NULL) {
diff --git a/source3/libsmb/clireadwrite.c b/source3/libsmb/clireadwrite.c
index 9bd81706730..13c024a2642 100644
--- a/source3/libsmb/clireadwrite.c
+++ b/source3/libsmb/clireadwrite.c
@@ -262,6 +262,14 @@ struct async_req *cli_pull_send(TALLOC_CTX *mem_ctx, struct cli_state *cli,
 
 	state->pushed = 0;
 	state->top_req = 0;
+
+	if (size == 0) {
+		if (!async_post_status(result, NT_STATUS_OK)) {
+			goto failed;
+		}
+		return result;
+	}
+
 	state->chunk_size = cli_read_max_bufsize(cli);
 
 	state->num_reqs = MAX(window_size/state->chunk_size, 1);