fbdev: omapfb: Fix an OF node leak in dss_of_port_get_parent_device()

JIRA: https://issues.redhat.com/browse/RHEL-75959
Upstream Status: v6.14-rc1

commit de124b6
Author:     Joe Hattori <[email protected]>
AuthorDate: Wed Jan  8 10:15:37 2025 +0900
Commit:     Helge Deller <[email protected]>
CommitDate: Thu Jan  9 00:35:09 2025 +0100

    dss_of_port_get_parent_device() leaks an OF node reference when i >= 2
    and struct device_node *np is present. Since of_get_next_parent()
    obtains a reference of the returned OF node, call of_node_put() before
    returning NULL.

    This was found by an experimental verifier that I am developing, and no
    runtime test was able to be performed due to that lack of actual
    devices.

    Fixes: f76ee89 ("omapfb: copy omapdss & displays for omapfb")
    Signed-off-by: Joe Hattori <[email protected]>
    Reviewed-by: Laurent Pinchart <[email protected]>
    Signed-off-by: Helge Deller <[email protected]>

Signed-off-by: Jocelyn Falempe <[email protected]>

Author: Jocelyn Falempe

drivers/video/fbdev/omap2/omapfb/dss/dss-of.c

@@ -36,6 +36,7 @@ struct device_node *dss_of_port_get_parent_device(struct device_node *port)
 		np = of_get_next_parent(np);
 	}
 
+	of_node_put(np);
 	return NULL;
 }