[PATCH v3 net 1/1] wwan: core: Avoid returning NULL from wwan_create_dev()

From: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
To: "David S. Miller" <davem@davemloft.net>,
	Sergey Ryazanov <ryazanov.s.a@gmail.com>,
	Loic Poulain <loic.poulain@linaro.org>,
	netdev@vger.kernel.org, linux-kernel@vger.kernel.org
Cc: Johannes Berg <johannes@sipsolutions.net>,
	Jakub Kicinski <kuba@kernel.org>,
	Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Subject: [PATCH v3 net 1/1] wwan: core: Avoid returning NULL from wwan_create_dev()
Date: Wed, 11 Aug 2021 15:48:45 +0300	[thread overview]
Message-ID: <20210811124845.10955-1-andriy.shevchenko@linux.intel.com> (raw)

Make wwan_create_dev() to return either valid or error pointer,
In some cases it may return NULL. Prevent this by converting
it to the respective error pointer.

Fixes: 9a44c1cc6388 ("net: Add a WWAN subsystem")
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: Sergey Ryazanov <ryazanov.s.a@gmail.com>
Reviewed-by: Loic Poulain <loic.poulain@linaro.org>
---
v3: split from original series with fixed subject (Sergey)

 drivers/net/wwan/wwan_core.c | 12 ++++++++----
 1 file changed, 8 insertions(+), 4 deletions(-)

diff --git a/drivers/net/wwan/wwan_core.c b/drivers/net/wwan/wwan_core.c
index 674a81d79db3..35ece98134c0 100644
--- a/drivers/net/wwan/wwan_core.c
+++ b/drivers/net/wwan/wwan_core.c
@@ -164,11 +164,14 @@ static struct wwan_device *wwan_create_dev(struct device *parent)
 		goto done_unlock;
 
 	id = ida_alloc(&wwan_dev_ids, GFP_KERNEL);
-	if (id < 0)
+	if (id < 0) {
+		wwandev = ERR_PTR(id);
 		goto done_unlock;
+	}
 
 	wwandev = kzalloc(sizeof(*wwandev), GFP_KERNEL);
 	if (!wwandev) {
+		wwandev = ERR_PTR(-ENOMEM);
 		ida_free(&wwan_dev_ids, id);
 		goto done_unlock;
 	}
@@ -182,7 +185,8 @@ static struct wwan_device *wwan_create_dev(struct device *parent)
 	err = device_register(&wwandev->dev);
 	if (err) {
 		put_device(&wwandev->dev);
-		wwandev = NULL;
+		wwandev = ERR_PTR(err);
+		goto done_unlock;
 	}
 
 done_unlock:
@@ -1014,8 +1018,8 @@ int wwan_register_ops(struct device *parent, const struct wwan_ops *ops,
 		return -EINVAL;
 
 	wwandev = wwan_create_dev(parent);
-	if (!wwandev)
-		return -ENOMEM;
+	if (IS_ERR(wwandev))
+		return PTR_ERR(wwandev);
 
 	if (WARN_ON(wwandev->ops)) {
 		wwan_remove_dev(wwandev);
-- 
2.30.2

