[PATCH] ASoC: sdw_utils: fix device reference leak in is_sdca_endpoint_present()

[Miaoqian Lin]

The bus_find_device_by_name() function returns a device pointer with an
incremented reference count, but the original code was missing put_device()
calls in some return paths, leading to reference count leaks.

Fix this by ensuring put_device() is called before function exit after
  bus_find_device_by_name() succeeds

This follows the same pattern used elsewhere in the kernel where
bus_find_device_by_name() is properly paired with put_device().

Found via static analysis and code review.

Fixes: 4f8ef33dd44a ("ASoC: soc_sdw_utils: skip the endpoint that doesn't present")
Cc: stable@xxxxxxxxxxxxxxx
Signed-off-by: Miaoqian Lin <linmq006@xxxxxxxxx>
---
 sound/soc/sdw_utils/soc_sdw_utils.c | 20 ++++++++++++++------
 1 file changed, 14 insertions(+), 6 deletions(-)

diff --git a/sound/soc/sdw_utils/soc_sdw_utils.c b/sound/soc/sdw_utils/soc_sdw_utils.c
index 270c66b90228..ea594f84f11a 100644
--- a/sound/soc/sdw_utils/soc_sdw_utils.c
+++ b/sound/soc/sdw_utils/soc_sdw_utils.c
@@ -1278,7 +1278,7 @@ static int is_sdca_endpoint_present(struct device *dev,
 	struct sdw_slave *slave;
 	struct device *sdw_dev;
 	const char *sdw_codec_name;
-	int i;
+	int ret, i;
 
 	dlc = kzalloc(sizeof(*dlc), GFP_KERNEL);
 	if (!dlc)
@@ -1308,13 +1308,16 @@ static int is_sdca_endpoint_present(struct device *dev,
 	}
 
 	slave = dev_to_sdw_dev(sdw_dev);
-	if (!slave)
-		return -EINVAL;
+	if (!slave) {
+		ret = -EINVAL;
+		goto put_device;
+	}
 
 	/* Make sure BIOS provides SDCA properties */
 	if (!slave->sdca_data.interface_revision) {
 		dev_warn(&slave->dev, "SDCA properties not found in the BIOS\n");
-		return 1;
+		ret = 1;
+		goto put_device;
 	}
 
 	for (i = 0; i < slave->sdca_data.num_functions; i++) {
@@ -1323,7 +1326,8 @@ static int is_sdca_endpoint_present(struct device *dev,
 		if (dai_type == dai_info->dai_type) {
 			dev_dbg(&slave->dev, "DAI type %d sdca function %s found\n",
 				dai_type, slave->sdca_data.function[i].name);
-			return 1;
+			ret = 1;
+			goto put_device;
 		}
 	}
 
@@ -1331,7 +1335,11 @@ static int is_sdca_endpoint_present(struct device *dev,
 		"SDCA device function for DAI type %d not supported, skip endpoint\n",
 		dai_info->dai_type);
 
-	return 0;
+	ret = 0;
+
+put_device:
+	put_device(sdw_dev);
+	return ret;
 }
 
 int asoc_sdw_parse_sdw_endpoints(struct snd_soc_card *card,
-- 
2.39.5 (Apple Git-154)