nl80211: fix locking in nl80211_set_tx_bitrate_mask()

This accesses the wdev's chandef etc., so cannot safely
be used without holding the lock.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Link: https://lore.kernel.org/r/20220506102136.06b7205419e6.I2a87c05fbd8bc5e565e84d190d4cfd2e92695a90@changeid
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

diff --git a/net/wireless/nl80211.c b/net/wireless/nl80211.c
index aa6094c..1a3551b 100644 (file)
--- a/net/wireless/nl80211.c
+++ b/net/wireless/nl80211.c
@@ -11666,18 +11666,23 @@ static int nl80211_set_tx_bitrate_mask(struct sk_buff *skb,
        struct cfg80211_bitrate_mask mask;
        struct cfg80211_registered_device *rdev = info->user_ptr[0];
        struct net_device *dev = info->user_ptr[1];
+       struct wireless_dev *wdev = dev->ieee80211_ptr;
        int err;
 
        if (!rdev->ops->set_bitrate_mask)
                return -EOPNOTSUPP;
 
+       wdev_lock(wdev);
        err = nl80211_parse_tx_bitrate_mask(info, info->attrs,
                                            NL80211_ATTR_TX_RATES, &mask,
                                            dev, true);
        if (err)
-               return err;
+               goto out;
 
-       return rdev_set_bitrate_mask(rdev, dev, NULL, &mask);
+       err = rdev_set_bitrate_mask(rdev, dev, NULL, &mask);
+out:
+       wdev_unlock(wdev);
+       return err;
 }
 
 static int nl80211_register_mgmt(struct sk_buff *skb, struct genl_info *info)