of: property: decrement node refcount in of_fwnode_get_reference_args()

stable inclusion
from stable-v4.19.268
commit 171d5fcca1e38b719bfe9b05cf0675f37e1c9d86
category: bugfix
bugzilla: https://gitee.com/openeuler/kernel/issues/I69KBO
CVE: NA

--------------------------------

[ Upstream commit 60d865bd ]

In of_fwnode_get_reference_args(), the refcount of of_args.np has
been incremented in the case of successful return from
of_parse_phandle_with_args() or of_parse_phandle_with_fixed_args().

Decrement the refcount if of_args is not returned to the caller of
of_fwnode_get_reference_args().

Fixes: 3e3119d3 ("device property: Introduce fwnode_property_get_reference_args")
Signed-off-by: NYang Yingliang <yangyingliang@huawei.com>
Reviewed-by: NSakari Ailus <sakari.ailus@linux.intel.com>
Reviewed-by: NFrank Rowand <frowand.list@gmail.com>
Link: https://lore.kernel.org/r/20221121023209.3909759-1-yangyingliang@huawei.comSigned-off-by: NRob Herring <robh@kernel.org>
Signed-off-by: NSasha Levin <sashal@kernel.org>
Signed-off-by: NYongqiang Liu <liuyongqiang13@huawei.com>

drivers/of/property.c

@@ -918,8 +918,10 @@ of_fwnode_get_reference_args(const struct fwnode_handle *fwnode,
 						       nargs, index, &of_args);
 	if (ret < 0)
 		return ret;
-	if (!args)
+	if (!args) {
+		of_node_put(of_args.np);
 		return 0;
+	}
 
 	args->nargs = of_args.args_count;
 	args->fwnode = of_fwnode_handle(of_args.np);