fpga: region: release of_parse_phandle nodes after use

BugLink: http://bugs.launchpad.net/bugs/1748072

commit 0f5eb15 upstream.

Both fpga_region_get_manager() and fpga_region_get_bridges() call
of_parse_phandle(), but nothing calls of_node_put() on the returned
struct device_node pointers.  Make sure to do that to stop their
reference counters getting out of whack.

Fixes: 0fa20cd ("fpga: fpga-region: device tree control for FPGA")
Signed-off-by: Ian Abbott <abbotti@mev.co.uk>
Signed-off-by: Alan Tull <atull@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Seth Forshee <seth.forshee@canonical.com>

drivers/fpga/fpga-region.c

@@ -147,6 +147,7 @@ static struct fpga_manager *fpga_region_get_manager(struct fpga_region *region)
 			mgr_node = of_parse_phandle(np, "fpga-mgr", 0);
 			if (mgr_node) {
 				mgr = of_fpga_mgr_get(mgr_node);
+				of_node_put(mgr_node);
 				of_node_put(np);
 				return mgr;
 			}
@@ -192,23 +193,29 @@ static int fpga_region_get_bridges(struct fpga_region *region,
 		parent_br = region_np->parent;
 
 	/* If overlay has a list of bridges, use it. */
-	if (of_parse_phandle(overlay, "fpga-bridges", 0))
+	br = of_parse_phandle(overlay, "fpga-bridges", 0);
+	if (br) {
+		of_node_put(br);
 		np = overlay;
-	else
+	} else {
 		np = region_np;
+	}
 
 	for (i = 0; ; i++) {
 		br = of_parse_phandle(np, "fpga-bridges", i);
 		if (!br)
 			break;
 
 		/* If parent bridge is in list, skip it. */
-		if (br == parent_br)
+		if (br == parent_br) {
+			of_node_put(br);
 			continue;
+		}
 
 		/* If node is a bridge, get it and add to list */
 		ret = fpga_bridge_get_to_list(br, region->info,
 					      &region->bridge_list);
+		of_node_put(br);
 
 		/* If any of the bridges are in use, give up */
 		if (ret == -EBUSY) {