[PATCH 4.4 37/54] libertas: register sysfs groups properly

Greg Kroah-Hartman
2021-05-31T13:19:22Z

From: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

[ Upstream commit 7e79b38fe9a403b065ac5915465f620a8fb3de84 ]

The libertas driver was trying to register sysfs groups "by hand" which
causes them to be created _after_ the device is initialized and
announced to userspace, which causes races and can prevent userspace
tools from seeing the sysfs files correctly.

Fix this up by using the built-in sysfs_groups pointers in struct
net_device which were created for this very reason, fixing the race
condition, and properly allowing for any error that might have occured
to be handled properly.

Cc: Kalle Valo <kvalo@codeaurora.org>
Link: https://lore.kernel.org/r/20210503115736.2104747-54-gregkh@linuxfoundation.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/net/wireless/libertas/mesh.c | 28 ++++------------------------
1 file changed, 4 insertions(+), 24 deletions(-)

diff --git a/drivers/net/wireless/libertas/mesh.c b/drivers/net/wireless/libertas/mesh.c
index d0c881dd5846..f1e9cbcfdc16 100644
--- a/drivers/net/wireless/libertas/mesh.c
+++ b/drivers/net/wireless/libertas/mesh.c
@@ -797,19 +797,6 @@ static const struct attribute_group mesh_ie_group = {
.attrs = mesh_ie_attrs,
};

-static void lbs_persist_config_init(struct net_device *dev)
-{
- int ret;
- ret = sysfs_create_group(&(dev->dev.kobj), &boot_opts_group);
- ret = sysfs_create_group(&(dev->dev.kobj), &mesh_ie_group);
-}
-
-static void lbs_persist_config_remove(struct net_device *dev)
-{
- sysfs_remove_group(&(dev->dev.kobj), &boot_opts_group);
- sysfs_remove_group(&(dev->dev.kobj), &mesh_ie_group);
-}
-

/***************************************************************************
* Initializing and starting, stopping mesh
@@ -1021,6 +1008,10 @@ static int lbs_add_mesh(struct lbs_private *priv)
SET_NETDEV_DEV(priv->mesh_dev, priv->dev->dev.parent);

mesh_dev->flags |= IFF_BROADCAST | IFF_MULTICAST;
+ mesh_dev->sysfs_groups[0] = &lbs_mesh_attr_group;
+ mesh_dev->sysfs_groups[1] = &boot_opts_group;
+ mesh_dev->sysfs_groups[2] = &mesh_ie_group;
+
/* Register virtual mesh interface */
ret = register_netdev(mesh_dev);
if (ret) {
@@ -1028,19 +1019,10 @@ static int lbs_add_mesh(struct lbs_private *priv)
goto err_free_netdev;
}

- ret = sysfs_create_group(&(mesh_dev->dev.kobj), &lbs_mesh_attr_group);
- if (ret)
- goto err_unregister;
-
- lbs_persist_config_init(mesh_dev);
-
/* Everything successful */
ret = 0;
goto done;

-err_unregister:
- unregister_netdev(mesh_dev);
-
err_free_netdev:
free_netdev(mesh_dev);

@@ -1063,8 +1045,6 @@ void lbs_remove_mesh(struct lbs_private *priv)
lbs_deb_enter(LBS_DEB_MESH);
netif_stop_queue(mesh_dev);
netif_carrier_off(mesh_dev);
- sysfs_remove_group(&(mesh_dev->dev.kobj), &lbs_mesh_attr_group);
- lbs_persist_config_remove(mesh_dev);
unregister_netdev(mesh_dev);
priv->mesh_dev = NULL;
kfree(mesh_dev->ieee80211_ptr);
--
2.30.2