serial/sunsu: fix refcount leak

The function of_find_node_by_path() acquires a reference to the node
returned by it and that reference needs to be dropped by its caller.

su_get_type() doesn't do that. The match node are used as an identifier
to compare against the current node, so we can directly drop the refcount
after getting the node from the path as it is not used as pointer.

Fix this by use a single variable and drop the refcount right after
of_find_node_by_path().

Signed-off-by: Yangtao Li <tiny.windzz@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Yangtao Li 2018-12-12 11:01:45 -05:00 committed by David S. Miller
parent afaffac368
commit d430aff8cd
1 changed files with 26 additions and 5 deletions

View File

@ -1394,22 +1394,43 @@ static inline struct console *SUNSU_CONSOLE(void)
static enum su_type su_get_type(struct device_node *dp)
{
struct device_node *ap = of_find_node_by_path("/aliases");
enum su_type rc = SU_PORT_PORT;
if (ap) {
const char *keyb = of_get_property(ap, "keyboard", NULL);
const char *ms = of_get_property(ap, "mouse", NULL);
struct device_node *match;
if (keyb) {
if (dp == of_find_node_by_path(keyb))
return SU_PORT_KBD;
match = of_find_node_by_path(keyb);
/*
* The pointer is used as an identifier not
* as a pointer, we can drop the refcount on
* the of__node immediately after getting it.
*/
of_node_put(match);
if (dp == match) {
rc = SU_PORT_KBD;
goto out;
}
}
if (ms) {
if (dp == of_find_node_by_path(ms))
return SU_PORT_MS;
match = of_find_node_by_path(ms);
of_node_put(match);
if (dp == match) {
rc = SU_PORT_MS;
goto out;
}
}
}
return SU_PORT_PORT;
out:
of_node_put(ap);
return rc;
}
static int su_probe(struct platform_device *op)