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From:   Jiasheng Jiang <jiasheng@iscas.ac.cn>
To:     quic_jjohnson@quicinc.co, agross@kernel.org,
        bjorn.andersson@linaro.org, konrad.dybcio@somainline.org
Cc:     linux-arm-msm@vger.kernel.org, linux-kernel@vger.kernel.org,
        Jiasheng Jiang <jiasheng@iscas.ac.cn>
Subject: [PATCH v3] soc: qcom: apr: Add check and kfree
Date:   Tue, 13 Sep 2022 16:05:06 +0800
Message-Id: <20220913080506.1733403-1-jiasheng@iscas.ac.cn>
MIME-Version: 1.0
Content-Transfer-Encoding: 8bit
Precedence: bulk

As idr_alloc() and of_property_read_string_index can return negative
numbers, it should be better to check the return value and deal with
the exception.
Moreover, if device_register() fails, the adev should also be freed in
order to avoid memory leak.
Therefore, it should be better to use goto statement to deal with the
exception.

Fixes: 6adba21eb434 ("soc: qcom: Add APR bus driver")
Signed-off-by: Jiasheng Jiang <jiasheng@iscas.ac.cn>
---
Changelog:

v2 -> v3:

1. Change the title and use goto statement to deal with the exception.

v1 -> v2:

1. Add dev_err and put_device in order to maintain the code consistency.
---
 drivers/soc/qcom/apr.c | 22 ++++++++++++++++++----
 1 file changed, 18 insertions(+), 4 deletions(-)

diff --git a/drivers/soc/qcom/apr.c b/drivers/soc/qcom/apr.c
index b4046f393575..b1a197155b2d 100644
--- a/drivers/soc/qcom/apr.c
+++ b/drivers/soc/qcom/apr.c
@@ -454,20 +454,34 @@ static int apr_add_device(struct device *dev, struct device_node *np,
 	adev->dev.driver = NULL;
 
 	spin_lock(&apr->svcs_lock);
-	idr_alloc(&apr->svcs_idr, svc, svc_id, svc_id + 1, GFP_ATOMIC);
+	ret = idr_alloc(&apr->svcs_idr, svc, svc_id, svc_id + 1, GFP_ATOMIC);
 	spin_unlock(&apr->svcs_lock);
+	if (ret < 0) {
+		dev_err(dev, "idr_alloc failed: %d\n", ret);
+		goto error;
+	}
 
-	of_property_read_string_index(np, "qcom,protection-domain",
-				      1, &adev->service_path);
+	ret = of_property_read_string_index(np, "qcom,protection-domain",
+					    1, &adev->service_path);
+	if (ret < 0) {
+		dev_err(dev, "of_property_read_string_index failed: %d\n", ret);
+		goto error;
+	}
 
 	dev_info(dev, "Adding APR/GPR dev: %s\n", dev_name(&adev->dev));
 
 	ret = device_register(&adev->dev);
 	if (ret) {
 		dev_err(dev, "device_register failed: %d\n", ret);
-		put_device(&adev->dev);
+		goto error;
 	}
 
+	goto end;
+
+error:
+	put_device(&adev->dev);
+	kfree(adev);
+end:
 	return ret;
 }
 
-- 
2.25.1