wwan: core: Avoid returning NULL from wwan_create_dev()

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>
Link: https://lore.kernel.org/r/20210811124845.10955-1-andriy.shevchenko@linux.intel.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

diff --git a/drivers/net/wwan/wwan_core.c b/drivers/net/wwan/wwan_core.c
index 674a81d79db3efffa522c964a2ab75c8655d368f..35ece98134c09793e88bb40de4370d67e143ce0f 100644 (file)
--- 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);