ASoc: audio-graph-card2: Fix refcount leak bug in __graph_get_type()

We should call of_node_put() for the reference before its replacement
as it returned by of_get_parent() which has increased the refcount.
Besides, we should also call of_node_put() before return.

Fixes: c8c74939f791 ("ASoC: audio-graph-card2: add Multi CPU/Codec support")
Signed-off-by: Liang He <windhl@126.com>
Link: https://lore.kernel.org/r/20220713071200.366729-1-windhl@126.com
Signed-off-by: Mark Brown <broonie@kernel.org>

diff --git a/sound/soc/generic/audio-graph-card2.c b/sound/soc/generic/audio-graph-card2.c
index 19e31d5..18d053a 100644 (file)
--- a/sound/soc/generic/audio-graph-card2.c
+++ b/sound/soc/generic/audio-graph-card2.c
@@ -229,7 +229,8 @@ enum graph_type {
 
 static enum graph_type __graph_get_type(struct device_node *lnk)
 {
-       struct device_node *np;
+       struct device_node *np, *parent_np;
+       enum graph_type ret;
 
        /*
         * target {
@@ -240,19 +241,33 @@ static enum graph_type __graph_get_type(struct device_node *lnk)
         * };
         */
        np = of_get_parent(lnk);
-       if (of_node_name_eq(np, "ports"))
-               np = of_get_parent(np);
+       if (of_node_name_eq(np, "ports")) {
+               parent_np = of_get_parent(np);
+               of_node_put(np);
+               np = parent_np;
+       }
 
-       if (of_node_name_eq(np, GRAPH_NODENAME_MULTI))
-               return GRAPH_MULTI;
+       if (of_node_name_eq(np, GRAPH_NODENAME_MULTI)) {
+               ret = GRAPH_MULTI;
+               goto out_put;
+       }
 
-       if (of_node_name_eq(np, GRAPH_NODENAME_DPCM))
-               return GRAPH_DPCM;
+       if (of_node_name_eq(np, GRAPH_NODENAME_DPCM)) {
+               ret = GRAPH_DPCM;
+               goto out_put;
+       }
 
-       if (of_node_name_eq(np, GRAPH_NODENAME_C2C))
-               return GRAPH_C2C;
+       if (of_node_name_eq(np, GRAPH_NODENAME_C2C)) {
+               ret = GRAPH_C2C;
+               goto out_put;
+       }
+
+       ret = GRAPH_NORMAL;
+
+out_put:
+       of_node_put(np);
+       return ret;
 
-       return GRAPH_NORMAL;
 }
 
 static enum graph_type graph_get_type(struct asoc_simple_priv *priv,