mac80211: fix receiving deauth
Marcel reported a warning, which quite obviously comes
from an oversight in the code handling deauth frames,
and which resulted in multiple follow-up warnings due
to this missing handling. This patch adds the missing
deauth handling (telling cfg80211 about it) and also
removes the follow-up warnings since they could happen
due to races even if nothing is wrong. I've explained
the races in the comments.
Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Reported-by: Marcel Holtmann <marcel@holtmann.org>
Tested-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
diff --git a/net/mac80211/mlme.c b/net/mac80211/mlme.c
index 76c03da..f60a831 100644
--- a/net/mac80211/mlme.c
+++ b/net/mac80211/mlme.c
@@ -2003,6 +2003,9 @@
case RX_MGMT_CFG80211_ASSOC:
cfg80211_send_rx_assoc(sdata->dev, (u8 *) mgmt, skb->len);
break;
+ case RX_MGMT_CFG80211_DEAUTH:
+ cfg80211_send_deauth(sdata->dev, (u8 *)mgmt, skb->len, NULL);
+ break;
default:
WARN(1, "unexpected: %d", rma);
}
@@ -2498,8 +2501,13 @@
}
}
- /* cfg80211 should catch this... */
- if (WARN_ON(!bssid)) {
+ /*
+ * cfg80211 should catch this ... but it's racy since
+ * we can receive a deauth frame, process it, hand it
+ * to cfg80211 while that's in a locked section already
+ * trying to tell us that the user wants to disconnect.
+ */
+ if (!bssid) {
mutex_unlock(&ifmgd->mtx);
return -ENOLINK;
}
@@ -2524,8 +2532,13 @@
mutex_lock(&ifmgd->mtx);
- /* cfg80211 should catch that */
- if (WARN_ON(&ifmgd->associated->cbss != req->bss)) {
+ /*
+ * cfg80211 should catch this ... but it's racy since
+ * we can receive a disassoc frame, process it, hand it
+ * to cfg80211 while that's in a locked section already
+ * trying to tell us that the user wants to disconnect.
+ */
+ if (&ifmgd->associated->cbss != req->bss) {
mutex_unlock(&ifmgd->mtx);
return -ENOLINK;
}
