From 225553f93e1e1dfa10114f3b5dc7cbd187ea64bd Mon Sep 17 00:00:00 2001
From: Dafydd Harries <daf@debian.org>
Date: Fri, 30 Mar 2018 10:57:18 -0400
Subject: [PATCH] fix timeout path for starting ssh-agent

Previously, GkdSsshAgentProcess would busy-loop waiting for the agent to time
out. If the agent never produced any output, it would busy-loop forever. (This
seems like it was because it would call g_main_context_iterate with
may_block=FALSE, preventing the timeout source from firing.)

Instead, have GkdSsshAgentProcess create a GMainLoop that's run until the agent starts or a timeout is reached.
---
 daemon/ssh-agent/gkd-ssh-agent-process.c | 38 +++++++++++++++++++++++++-------
 daemon/ssh-agent/gkd-ssh-agent-service.c |  5 ++++-
 2 files changed, 34 insertions(+), 9 deletions(-)

diff --git a/daemon/ssh-agent/gkd-ssh-agent-process.c b/daemon/ssh-agent/gkd-ssh-agent-process.c
index d3bb3a7e..edf97630 100644
--- a/daemon/ssh-agent/gkd-ssh-agent-process.c
+++ b/daemon/ssh-agent/gkd-ssh-agent-process.c
@@ -53,6 +53,7 @@ struct _GkdSshAgentProcess
 	guint output_id;
 	guint child_id;
 	gboolean ready;
+	GMainLoop *ready_loop;
 };
 
 G_DEFINE_TYPE (GkdSshAgentProcess, gkd_ssh_agent_process, G_TYPE_OBJECT);
@@ -160,6 +161,10 @@ on_output_watch (gint fd,
 	if (condition & G_IO_IN) {
 		self->ready = TRUE;
 
+		if (self->ready_loop) {
+			g_main_loop_quit (self->ready_loop);
+		}
+
 		len = read (fd, buf, sizeof (buf));
 		if (len < 0) {
 			if (errno != EAGAIN && errno != EINTR)
@@ -179,6 +184,7 @@ agent_start_inlock (GkdSshAgentProcess *self,
 		    GError **error)
 {
 	const gchar *argv[] = { SSH_AGENT, "-D", "-a", self->path, NULL };
+
 	GPid pid;
 
 	if (!g_spawn_async_with_pipes ("/", (gchar **)argv, NULL, G_SPAWN_DO_NOT_REAP_CHILD,
@@ -199,19 +205,38 @@ agent_start_inlock (GkdSshAgentProcess *self,
 static gboolean
 on_timeout (gpointer user_data)
 {
-	gboolean *timedout = user_data;
-	*timedout = TRUE;
+	GkdSshAgentProcess *self = user_data;
+
+	if (self->ready_loop) {
+		g_main_loop_quit (self->ready_loop);
+	}
+
 	return TRUE;
 }
 
+static void
+wait_for_agent (GkdSshAgentProcess *self)
+{
+	guint source;
+
+	if (self->ready_loop) {
+		g_main_loop_run (self->ready_loop);
+	} else {
+		self->ready_loop = g_main_loop_new (NULL, FALSE);
+		source = g_timeout_add_seconds (3, on_timeout, self);
+		g_main_loop_run (self->ready_loop);
+		g_source_remove (source);
+		g_main_loop_unref (self->ready_loop);
+		self->ready_loop = NULL;
+	}
+}
+
 GSocketConnection *
 gkd_ssh_agent_process_connect (GkdSshAgentProcess *self,
 			       GCancellable *cancellable,
 			       GError **error)
 {
 	gboolean started = FALSE;
-	gboolean timedout = FALSE;
-	guint source;
 	GSocketClient *client;
 	GSocketAddress *address;
 	GSocketConnection *connection;
@@ -227,10 +252,7 @@ gkd_ssh_agent_process_connect (GkdSshAgentProcess *self,
 	}
 
 	if (started && !self->ready) {
-		source = g_timeout_add_seconds (5, on_timeout, &timedout);
-		while (!self->ready && !timedout)
-			g_main_context_iteration (NULL, FALSE);
-		g_source_remove (source);
+		wait_for_agent (self);
 	}
 
 	if (!self->ready) {
diff --git a/daemon/ssh-agent/gkd-ssh-agent-service.c b/daemon/ssh-agent/gkd-ssh-agent-service.c
index a9f74ab3..1ebbe381 100644
--- a/daemon/ssh-agent/gkd-ssh-agent-service.c
+++ b/daemon/ssh-agent/gkd-ssh-agent-service.c
@@ -348,7 +348,10 @@ on_run (GThreadedSocketService *service,
 	egg_buffer_uninit (&req);
 	egg_buffer_uninit (&resp);
 
-	g_object_unref (agent_connection);
+	if (agent_connection) {
+		g_object_unref (agent_connection);
+	}
+
 	g_object_unref (self);
 
 	return TRUE;
-- 
2.16.3