[PATCH v3] iio: dummy: iio_simple_dummy: check the return value of kstrdup()

[xkernel . wang]

From: Xiaoke Wang <xkernel.wang@xxxxxxxxxxx>

kstrdup() is also a memory allocation-related function, it returns NULL
when some memory errors happen. So it is better to check the return
value of it so to catch the memory error in time. Besides, there should
have a kfree() to clear up the allocation if we get a failure later in
this function to prevent memory leak.

Signed-off-by: Xiaoke Wang <xkernel.wang@xxxxxxxxxxx>
---
I am sorry that I forgot to send this.
Changelogs:
v1->v2 add kfree() on the error path.
v2->v3 change the err lable.
 drivers/iio/dummy/iio_simple_dummy.c | 17 ++++++++++-------
 1 file changed, 10 insertions(+), 7 deletions(-)

diff --git a/drivers/iio/dummy/iio_simple_dummy.c b/drivers/iio/dummy/iio_simple_dummy.c
index c0b7ef9..99e7731 100644
--- a/drivers/iio/dummy/iio_simple_dummy.c
+++ b/drivers/iio/dummy/iio_simple_dummy.c
@@ -575,10 +575,9 @@ static struct iio_sw_device *iio_dummy_probe(const char *name)
 	 */
 
 	swd = kzalloc(sizeof(*swd), GFP_KERNEL);
-	if (!swd) {
-		ret = -ENOMEM;
-		goto error_kzalloc;
-	}
+	if (!swd)
+		return ERR_PTR(-ENOMEM);
+
 	/*
 	 * Allocate an IIO device.
 	 *
@@ -590,7 +589,7 @@ static struct iio_sw_device *iio_dummy_probe(const char *name)
 	indio_dev = iio_device_alloc(parent, sizeof(*st));
 	if (!indio_dev) {
 		ret = -ENOMEM;
-		goto error_ret;
+		goto error_free_swd;
 	}
 
 	st = iio_priv(indio_dev);
@@ -616,6 +615,10 @@ static struct iio_sw_device *iio_dummy_probe(const char *name)
 	 *    indio_dev->name = spi_get_device_id(spi)->name;
 	 */
 	indio_dev->name = kstrdup(name, GFP_KERNEL);
+	if (!indio_dev->name) {
+		ret = -ENOMEM;
+		goto error_free_device;
+	}
 
 	/* Provide description of available channels */
 	indio_dev->channels = iio_dummy_channels;
@@ -650,10 +653,10 @@ static struct iio_sw_device *iio_dummy_probe(const char *name)
 error_unregister_events:
 	iio_simple_dummy_events_unregister(indio_dev);
 error_free_device:
+	kfree(indio_dev->name);
 	iio_device_free(indio_dev);
-error_ret:
+error_free_swd:
 	kfree(swd);
-error_kzalloc:
 	return ERR_PTR(ret);
 }
 
--