[Spice-devel] [spice-gtk v1] channel-webdav: Do not crash if no PhodavServer is found

[Victor Toso]

From: Victor Toso <me at victortoso.com>

This fixes a crash when spice_session_get_webdav_server() returns NULL
which can easily happen if no shared folder is set.

We still lack a way to tell the Guest about the failure as it waits
the data to mount the shared folder.

Log:
> (spicy:20825): phodav-CRITICAL **: phodav_server_get_soup_server: assertion
> 'PHODAV_IS_SERVER (self)' failed
> (spicy:20825): GSpice-DEBUG: channel-webdav.c:368 webdav-11:0: starting client
> -1812687888
>
> (spicy:20825): GLib-GObject-CRITICAL **: g_type_instance_get_private: assertion
> 'instance != NULL && instance->g_class != NULL' failed
>
> Thread 1 "spicy" received signal SIGSEGV, Segmentation fault.
> soup_server_accept_socket (server=server at entry=0x0, sock=sock at entry=0x7f7670
>
> [SoupSocket]) at soup-server.c:1468
> 1468            priv->clients = g_slist_prepend (priv->clients, client);

Backtrace:
> (gdb) bt
> #0  in soup_server_accept_socket (server=server at entry=0x0,
>     sock=sock at entry=0x7f7670[SoupSocket]) at soup-server.c:1468
> #1  in soup_server_accept_iostream (server=0x0,
>     stream=0xb77890 [GSimpleIOStream], local_addr=<optimized out>,
>     remote_addr=<optimized out>, error=<optimized out>) at soup-server.c:1515
> #2  in start_client (self=0xa0a6e0 [SpiceWebdavChannel]) at channel-webdav.c:382
> #3  in data_read_cb (source_object=0x9d2e60 [SpiceVmcInputStream],
>     res=0x9d0e80, user_data=0xa0a6e0) at channel-webdav.c:429
> #4  in g_task_return_now (task=0x9d0e80 [GTask]) at gtask.c:1121
> #5  in g_task_return (task=0x9d0e80 [GTask], type=<optimized out>) at gtask.c:1179
> #6  in complete_in_idle_cb (user_data=0x1233070) at vmcstream.c:110

Signed-off-by: Victor Toso <victortoso at redhat.com>
---
 src/channel-webdav.c | 8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/src/channel-webdav.c b/src/channel-webdav.c
index 4a246b5..38de2fb 100644
--- a/src/channel-webdav.c
+++ b/src/channel-webdav.c
@@ -361,9 +361,15 @@ static void start_client(SpiceWebdavChannel *self)
     SoupServer *server;
     GSocketAddress *addr;
     GError *error = NULL;
+    PhodavServer *phodav;
 
     session = spice_channel_get_session(SPICE_CHANNEL(self));
-    server = phodav_server_get_soup_server(spice_session_get_webdav_server(session));
+    phodav = spice_session_get_webdav_server(session);
+    if (phodav == NULL) {
+        CHANNEL_DEBUG(self, "failed to start client: no Phodav Server");
+        return;
+    }
+    server = phodav_server_get_soup_server(phodav);
 
     CHANNEL_DEBUG(self, "starting client %" G_GINT64_FORMAT, c->demux.client);
 
-- 
2.9.3