ASoC: simple-card: fix an use-after-free in simple_for_each_link()

The codec variable is still being used after the of_node_put() call,
which may result in use-after-free.

Fixes: d947cdfd4be2 ("ASoC: simple-card: cleanup DAI link loop method - step1")
Link: https://lore.kernel.org/r/1562743509-30496-3-git-send-email-wen.yang99@zte.com.cn
Signed-off-by: Wen Yang <wen.yang99@zte.com.cn>
Acked-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

diff --git a/sound/soc/generic/simple-card.c b/sound/soc/generic/simple-card.c
index 4117e54..ef84915 100644 (file)
--- a/sound/soc/generic/simple-card.c
+++ b/sound/soc/generic/simple-card.c
@@ -364,8 +364,6 @@ static int simple_for_each_link(struct asoc_simple_priv *priv,
                        goto error;
                }
 
-               of_node_put(codec);
-
                /* get convert-xxx property */
                memset(&adata, 0, sizeof(adata));
                for_each_child_of_node(node, np)
@@ -387,11 +385,13 @@ static int simple_for_each_link(struct asoc_simple_priv *priv,
                                ret = func_noml(priv, np, codec, li, is_top);
 
                        if (ret < 0) {
+                               of_node_put(codec);
                                of_node_put(np);
                                goto error;
                        }
                }
 
+               of_node_put(codec);
                node = of_get_next_child(top, node);
        } while (!is_top && node);