[PATCH] ASoC: qcom: qdsp6: Fix device node leaks when parsing "iommus" phandle

[zhaofeng2]

From: Zhao Feng <zhaofeng2@xxxxxxxxxxxxxxxxxxxx>

q6asm_dai_probe(), q6apm_dai_probe() and q6usb_dai_dev_probe() parse
the "iommus" phandle with of_parse_phandle_with_fixed_args(), which
takes a reference on the iommu device node, but none of them drops
the reference after the stream ID has been read from args.args[0],
so the iommu node is leaked on every probe.

Drop the reference with of_node_put() after reading args.args[0].

This is a refreshed version of the fix posted by Selby Mashiki [1],
which no longer applies because the context in q6apm_dai_probe() has
changed since; the leaks are still present in all three functions.

Originally-by: Selby Mashiki <mashikiselby@xxxxxxxxx>
Link: https://lore.kernel.org/linux-sound/20261025190340.449613-1-mashikiselby@xxxxxxxxx/ [1]
Fixes: 2a9e92d371db ("ASoC: qdsp6: q6asm: Add q6asm dai driver")
Fixes: 9b4fe0f1cd79 ("ASoC: qdsp6: audioreach: add q6apm-dai support")
Fixes: 72b0b8b29980 ("ASoC: qcom: qdsp6: Add USB backend ASoC driver for Q6")
Signed-off-by: Zhao Feng <zhaofeng2@xxxxxxxxxxxxxxxxxxxx>
---
 sound/soc/qcom/qdsp6/q6apm-dai.c | 4 +++-
 sound/soc/qcom/qdsp6/q6asm-dai.c | 4 +++-
 sound/soc/qcom/qdsp6/q6usb.c | 4 +++-
 3 files changed, 9 insertions(+), 3 deletions(-)

diff --git a/sound/soc/qcom/qdsp6/q6apm-dai.c b/sound/soc/qcom/qdsp6/q6apm-dai.c
--- a/sound/soc/qcom/qdsp6/q6apm-dai.c
+++ b/sound/soc/qcom/qdsp6/q6apm-dai.c
@@ -1203,8 +1203,10 @@
 	rc = of_parse_phandle_with_fixed_args(node, "iommus", 1, 0, &args);
 	if (rc < 0)
 		pdata->sid = -1;
-	else
+	else {
 		pdata->sid = args.args[0] & SID_MASK_DEFAULT;
+		of_node_put(args.np);
+	}
 
 	if (apm && apm->gdev &&
 	    apm->gdev->domain_id == GPR_DOMAIN_ID_MODEM) {
diff --git a/sound/soc/qcom/qdsp6/q6asm-dai.c b/sound/soc/qcom/qdsp6/q6asm-dai.c
--- a/sound/soc/qcom/qdsp6/q6asm-dai.c
+++ b/sound/soc/qcom/qdsp6/q6asm-dai.c
@@ -1309,8 +1309,10 @@
 	rc = of_parse_phandle_with_fixed_args(node, "iommus", 1, 0, &args);
 	if (rc < 0)
 		pdata->sid = -1;
-	else
+	else {
 		pdata->sid = args.args[0] & SID_MASK_DEFAULT;
+		of_node_put(args.np);
+	}
 
 	dev_set_drvdata(dev, pdata);
 
diff --git a/sound/soc/qcom/qdsp6/q6usb.c b/sound/soc/qcom/qdsp6/q6usb.c
--- a/sound/soc/qcom/qdsp6/q6usb.c
+++ b/sound/soc/qcom/qdsp6/q6usb.c
@@ -382,8 +382,10 @@
 	}
 
 	ret = of_parse_phandle_with_fixed_args(node, "iommus", 1, 0, &args);
-	if (!ret)
+	if (!ret) {
 		data->priv.sid = args.args[0] & Q6_USB_SID_MASK;
+		of_node_put(args.np);
+	}
 
 	ret = devm_mutex_init(dev, &data->mutex);
 	if (ret < 0)