cfg80211: fix NULL ptr deref
commit 211a4d12abf86fe0df4cd68fc6327cbb58f56f81
Author: Johannes Berg <johannes@sipsolutions.net>
Date: Tue Oct 20 15:08:53 2009 +0900
cfg80211: sme: deauthenticate on assoc failure
introduced a potential NULL pointer dereference that
some people have been hitting for some reason -- the
params.bssid pointer is not guaranteed to be non-NULL
for what seems to be a race between various ways of
reaching the same thing.
While I'm trying to analyse the problem more let's
first fix the crash. I think the real fix may be to
avoid doing _anything_ if it ended up being NULL, but
right now I'm not sure yet.
I think
http://bugzilla.kernel.org/show_bug.cgi?id=14342
might also be this issue.
Reported-by: Parag Warudkar <parag.lkml@gmail.com>
Tested-by: Parag Warudkar <parag.lkml@gmail.com>
Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
diff --git a/net/wireless/sme.c b/net/wireless/sme.c
index ece378d..9f0b280 100644
--- a/net/wireless/sme.c
+++ b/net/wireless/sme.c
@@ -165,7 +165,7 @@
struct cfg80211_registered_device *rdev =
container_of(work, struct cfg80211_registered_device, conn_work);
struct wireless_dev *wdev;
- u8 bssid[ETH_ALEN];
+ u8 bssid_buf[ETH_ALEN], *bssid = NULL;
rtnl_lock();
cfg80211_lock_rdev(rdev);
@@ -181,7 +181,10 @@
wdev_unlock(wdev);
continue;
}
- memcpy(bssid, wdev->conn->params.bssid, ETH_ALEN);
+ if (wdev->conn->params.bssid) {
+ memcpy(bssid_buf, wdev->conn->params.bssid, ETH_ALEN);
+ bssid = bssid_buf;
+ }
if (cfg80211_conn_do_work(wdev))
__cfg80211_connect_result(
wdev->netdev, bssid,