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From:   Liang He <windhl@126.com>
To:     herbert@gondor.apana.org.au, davem@davemloft.net,
        linux-crypto@vger.kernel.org, windhl@126.com
Subject: [PATCH] crypto: Hold the reference returned by of_find_compatible_node
Date:   Tue, 21 Jun 2022 15:37:42 +0800
Message-Id: <20220621073742.4081013-1-windhl@126.com>
MIME-Version: 1.0
Content-Transfer-Encoding: 8bit
Precedence: bulk

In nx842_pseries_init() and crypto4xx_probe(), we should hold the
reference returned by of_find_compatible_node() and use it to call
of_node_put to keep refcount balance.

Signed-off-by: Liang He <windhl@126.com>
---
 drivers/crypto/amcc/crypto4xx_core.c  | 13 ++++++++-----
 drivers/crypto/nx/nx-common-pseries.c |  5 ++++-
 2 files changed, 12 insertions(+), 6 deletions(-)

diff --git a/drivers/crypto/amcc/crypto4xx_core.c b/drivers/crypto/amcc/crypto4xx_core.c
index 8278d98074e9..169b6a05e752 100644
--- a/drivers/crypto/amcc/crypto4xx_core.c
+++ b/drivers/crypto/amcc/crypto4xx_core.c
@@ -1378,6 +1378,7 @@ static int crypto4xx_probe(struct platform_device *ofdev)
 	struct resource res;
 	struct device *dev = &ofdev->dev;
 	struct crypto4xx_core_device *core_dev;
+	struct device_node *np;
 	u32 pvr;
 	bool is_revb = true;
 
@@ -1385,20 +1386,20 @@ static int crypto4xx_probe(struct platform_device *ofdev)
 	if (rc)
 		return -ENODEV;
 
-	if (of_find_compatible_node(NULL, NULL, "amcc,ppc460ex-crypto")) {
+	if ((np = of_find_compatible_node(NULL, NULL, "amcc,ppc460ex-crypto")) != NULL) {
 		mtdcri(SDR0, PPC460EX_SDR0_SRST,
 		       mfdcri(SDR0, PPC460EX_SDR0_SRST) | PPC460EX_CE_RESET);
 		mtdcri(SDR0, PPC460EX_SDR0_SRST,
 		       mfdcri(SDR0, PPC460EX_SDR0_SRST) & ~PPC460EX_CE_RESET);
-	} else if (of_find_compatible_node(NULL, NULL,
-			"amcc,ppc405ex-crypto")) {
+	} else if ((np = of_find_compatible_node(NULL, NULL,
+			"amcc,ppc405ex-crypto")) != NULL) {
 		mtdcri(SDR0, PPC405EX_SDR0_SRST,
 		       mfdcri(SDR0, PPC405EX_SDR0_SRST) | PPC405EX_CE_RESET);
 		mtdcri(SDR0, PPC405EX_SDR0_SRST,
 		       mfdcri(SDR0, PPC405EX_SDR0_SRST) & ~PPC405EX_CE_RESET);
 		is_revb = false;
-	} else if (of_find_compatible_node(NULL, NULL,
-			"amcc,ppc460sx-crypto")) {
+	} else if ((np = of_find_compatible_node(NULL, NULL,
+			"amcc,ppc460sx-crypto")) != NULL) {
 		mtdcri(SDR0, PPC460SX_SDR0_SRST,
 		       mfdcri(SDR0, PPC460SX_SDR0_SRST) | PPC460SX_CE_RESET);
 		mtdcri(SDR0, PPC460SX_SDR0_SRST,
@@ -1408,6 +1409,8 @@ static int crypto4xx_probe(struct platform_device *ofdev)
 		return -EINVAL;
 	}
 
+	of_node_put(np);
+
 	core_dev = kzalloc(sizeof(struct crypto4xx_core_device), GFP_KERNEL);
 	if (!core_dev)
 		return -ENOMEM;
diff --git a/drivers/crypto/nx/nx-common-pseries.c b/drivers/crypto/nx/nx-common-pseries.c
index 7584a34ba88c..3ea334b7f820 100644
--- a/drivers/crypto/nx/nx-common-pseries.c
+++ b/drivers/crypto/nx/nx-common-pseries.c
@@ -1208,10 +1208,13 @@ static struct vio_driver nx842_vio_driver = {
 static int __init nx842_pseries_init(void)
 {
 	struct nx842_devdata *new_devdata;
+	struct device_node *np;
 	int ret;
 
-	if (!of_find_compatible_node(NULL, NULL, "ibm,compression"))
+	np = of_find_compatible_node(NULL, NULL, "ibm,compression");
+	if (!np)
 		return -ENODEV;
+	of_node_put(np);
 
 	RCU_INIT_POINTER(devdata, NULL);
 	new_devdata = kzalloc(sizeof(*new_devdata), GFP_KERNEL);
-- 
2.25.1