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From:   Anshuman Khandual <anshuman.khandual@arm.com>
To:     linux-arm-kernel@lists.infradead.org, suzuki.poulose@arm.com
Cc:     Anshuman Khandual <anshuman.khandual@arm.com>,
        Mike Leach <mike.leach@linaro.org>,
        James Clark <james.clark@arm.com>, coresight@lists.linaro.org,
        linux-kernel@vger.kernel.org,
        Dan Carpenter <dan.carpenter@linaro.org>
Subject: [PATCH] coresight: etm4x: Ensure valid drvdata and clock before clk_put()
Date:   Fri, 11 Aug 2023 11:57:38 +0530
Message-Id: <20230811062738.1066787-1-anshuman.khandual@arm.com>
MIME-Version: 1.0
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This validates 'drvdata' and 'drvdata->pclk' clock before calling clk_put()
in etm4_remove_platform_dev(). The problem was detected using Smatch static
checker as reported.

Cc: Suzuki K Poulose <suzuki.poulose@arm.com>
Cc: Mike Leach <mike.leach@linaro.org>
Cc: James Clark <james.clark@arm.com>
Cc: coresight@lists.linaro.org
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-kernel@vger.kernel.org
Reported-by: Dan Carpenter <dan.carpenter@linaro.org>
Closes: https://lists.linaro.org/archives/list/coresight@lists.linaro.org/thread/G4N6P4OXELPLLQSNU3GU2MR4LOLRXRMJ/
Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com>
---
This applies on coresight-next

 drivers/hwtracing/coresight/coresight-etm4x-core.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/hwtracing/coresight/coresight-etm4x-core.c b/drivers/hwtracing/coresight/coresight-etm4x-core.c
index 703b6fcbb6a5..eb412ce302cc 100644
--- a/drivers/hwtracing/coresight/coresight-etm4x-core.c
+++ b/drivers/hwtracing/coresight/coresight-etm4x-core.c
@@ -2269,7 +2269,7 @@ static int __exit etm4_remove_platform_dev(struct platform_device *pdev)
 		etm4_remove_dev(drvdata);
 	pm_runtime_disable(&pdev->dev);
 
-	if (drvdata->pclk)
+	if (drvdata && drvdata->pclk && !IS_ERR(drvdata->pclk))
 		clk_put(drvdata->pclk);
 
 	return 0;
-- 
2.25.1