cfg80211: fix race in giwrate
cfg80211_wext_giwrate doesn't lock the wdev, so it
cannot access current_bss race-free. Also, there's
little point in trying to ask the driver for an AP
that it never told us about, so avoid that case.
Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
diff --git a/net/wireless/wext-compat.c b/net/wireless/wext-compat.c
index 9d101d5..5088d89 100644
--- a/net/wireless/wext-compat.c
+++ b/net/wireless/wext-compat.c
@@ -1127,7 +1127,7 @@
struct cfg80211_registered_device *rdev = wiphy_to_dev(wdev->wiphy);
/* we are under RTNL - globally locked - so can use a static struct */
static struct station_info sinfo;
- u8 *addr;
+ u8 addr[ETH_ALEN];
int err;
if (wdev->iftype != NL80211_IFTYPE_STATION)
@@ -1136,12 +1136,15 @@
if (!rdev->ops->get_station)
return -EOPNOTSUPP;
+ err = 0;
+ wdev_lock(wdev);
if (wdev->current_bss)
- addr = wdev->current_bss->pub.bssid;
- else if (wdev->wext.connect.bssid)
- addr = wdev->wext.connect.bssid;
+ memcpy(addr, wdev->current_bss->pub.bssid, ETH_ALEN);
else
- return -EOPNOTSUPP;
+ err = -EOPNOTSUPP;
+ wdev_unlock(wdev);
+ if (err)
+ return err;
err = rdev->ops->get_station(&rdev->wiphy, dev, addr, &sinfo);
if (err)