ASoC: wcd934x: fix error handling in wcd934x_codec_parse_data()

wcd934x_codec_parse_data() contains a device reference count leak in
of_slim_get_device() where device_find_child() increases the reference
count of the device but this reference is not properly decreased in
the success path. Add put_device() in wcd934x_codec_parse_data() and
add devm_add_action_or_reset() in the probe function, which ensures
that the reference count of the device is correctly managed.

Memory leak in regmap_init_slimbus() as the allocated regmap is not
released when the device is removed. Using devm_regmap_init_slimbus()
instead of regmap_init_slimbus() to ensure automatic regmap cleanup on
device removal.

Calling path: of_slim_get_device() -> of_find_slim_device() ->
device_find_child(). As comment of device_find_child() says, 'NOTE:
you will need to drop the reference with put_device() after use.'.

Found by code review.

Cc: stable@vger.kernel.org
Fixes: a61f3b4f476e ("ASoC: wcd934x: add support to wcd9340/wcd9341 codec")
Signed-off-by: Ma Ke <make24@iscas.ac.cn>
Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@oss.qualcomm.com>
Link: https://patch.msgid.link/20250923065212.26660-1-make24@iscas.ac.cn
Signed-off-by: Mark Brown <broonie@kernel.org>

diff --git a/sound/soc/codecs/wcd934x.c b/sound/soc/codecs/wcd934x.c
index 1bb7e1dc7e6b0a5528cbdb7ada943a7d417fb684..e92939068bf75efb62e9eb5ecad1262c7df26f8b 100644 (file)
--- a/sound/soc/codecs/wcd934x.c
+++ b/sound/soc/codecs/wcd934x.c
@@ -5831,6 +5831,13 @@ static const struct snd_soc_component_driver wcd934x_component_drv = {
        .endianness = 1,
 };
 
+static void wcd934x_put_device_action(void *data)
+{
+       struct device *dev = data;
+
+       put_device(dev);
+}
+
 static int wcd934x_codec_parse_data(struct wcd934x_codec *wcd)
 {
        struct device *dev = &wcd->sdev->dev;
@@ -5847,11 +5854,13 @@ static int wcd934x_codec_parse_data(struct wcd934x_codec *wcd)
                return dev_err_probe(dev, -EINVAL, "Unable to get SLIM Interface device\n");
 
        slim_get_logical_addr(wcd->sidev);
-       wcd->if_regmap = regmap_init_slimbus(wcd->sidev,
+       wcd->if_regmap = devm_regmap_init_slimbus(wcd->sidev,
                                  &wcd934x_ifc_regmap_config);
-       if (IS_ERR(wcd->if_regmap))
+       if (IS_ERR(wcd->if_regmap)) {
+               put_device(&wcd->sidev->dev);
                return dev_err_probe(dev, PTR_ERR(wcd->if_regmap),
                                     "Failed to allocate ifc register map\n");
+       }
 
        of_property_read_u32(dev->parent->of_node, "qcom,dmic-sample-rate",
                             &wcd->dmic_sample_rate);
@@ -5893,6 +5902,10 @@ static int wcd934x_codec_probe(struct platform_device *pdev)
        if (ret)
                return ret;
 
+       ret = devm_add_action_or_reset(dev, wcd934x_put_device_action, &wcd->sidev->dev);
+       if (ret)
+               return ret;
+
        /* set default rate 9P6MHz */
        regmap_update_bits(wcd->regmap, WCD934X_CODEC_RPM_CLK_MCLK_CFG,
                           WCD934X_CODEC_RPM_CLK_MCLK_CFG_MCLK_MASK,