libxl: fix segfault on device assignement

Fix a xl/libxl segfault when assigning a device to the guest (bug
http://bugzilla.xensource.com/bugzilla/show_bug.cgi?id=1713).

Signed-off-by: Gianni Tedesco <gianni.tedesco@citrix.com>
Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Acked-by: Ian Campbell <ian.campbell@citrix.com>
Committed-by: Ian Jackson <ian.jackson@eu.citrix.com>

diff --git a/tools/libxl/libxl_pci.c b/tools/libxl/libxl_pci.c
index 349950c6552d24abaadeed1797898129696aa507..ba59650fde8128409a03927508878abe504e92b1 100644 (file)
--- a/tools/libxl/libxl_pci.c
+++ b/tools/libxl/libxl_pci.c
@@ -268,7 +268,7 @@ static int libxl_create_pci_backend(libxl__gc *gc, uint32_t domid, libxl_device_
     for (i = 0; i < num; i++, pcidev++)
         libxl_create_pci_backend_device(gc, back, i, pcidev);
 
-    flexarray_vappend(back, "num_devs", libxl__sprintf(gc, "%d", num));
+    flexarray_vappend(back, "num_devs", libxl__sprintf(gc, "%d", num), NULL);
 
     flexarray_vappend(front,
                       "backend-id", libxl__sprintf(gc, "%d", 0),