[PATCH 5.12 154/178] cfg80211: fix phy80211 symlink creation

Greg Kroah-Hartman
2021-06-21T16:50:39Z

From: Johannes Berg <johannes.berg@intel.com>

commit 43076c1e074359f11c85d7d1b85ede1bbb8ee6b9 upstream.

When I moved around the code here, I neglected that we could still
call register_netdev() or similar without the wiphy mutex held,
which then calls cfg80211_register_wdev() - that's also done from
cfg80211_register_netdevice(), but the phy80211 symlink creation
was only there. Now, the symlink isn't needed for a *pure* wdev,
but a netdev not registered via cfg80211_register_wdev() should
still have the symlink, so move the creation to the right place.

Cc: stable@vger.kernel.org
Fixes: 2fe8ef106238 ("cfg80211: change netdev registration/unregistration semantics")
Link: https://lore.kernel.org/r/20210608113226.a5dc4c1e488c.Ia42fe663cefe47b0883af78c98f284c5555bbe5d@changeid
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
net/wireless/core.c | 13 +++++--------
1 file changed, 5 insertions(+), 8 deletions(-)

--- a/net/wireless/core.c
+++ b/net/wireless/core.c
@@ -1339,6 +1339,11 @@ void cfg80211_register_wdev(struct cfg80
rdev->devlist_generation++;
wdev->registered = true;

+ if (wdev->netdev &&
+ sysfs_create_link(&wdev->netdev->dev.kobj, &rdev->wiphy.dev.kobj,
+ "phy80211"))
+ pr_err("failed to add phy80211 symlink to netdev!\n");
+
nl80211_notify_iface(rdev, wdev, NL80211_CMD_NEW_INTERFACE);
}

@@ -1364,14 +1369,6 @@ int cfg80211_register_netdevice(struct n
if (ret)
goto out;

- if (sysfs_create_link(&dev->dev.kobj, &rdev->wiphy.dev.kobj,
- "phy80211")) {
- pr_err("failed to add phy80211 symlink to netdev!\n");
- unregister_netdevice(dev);
- ret = -EINVAL;
- goto out;
- }
-
cfg80211_register_wdev(rdev, wdev);
ret = 0;