mac80211: fix RX skb leaks
In mac80211's RX path some of the warnings that
warn about drivers passing invalid status values
leak the skb, fix that by refactoring the code.
Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
diff --git a/net/mac80211/rx.c b/net/mac80211/rx.c
index b98f1af..c01588f 100644
--- a/net/mac80211/rx.c
+++ b/net/mac80211/rx.c
@@ -2447,17 +2447,13 @@
struct ieee80211_supported_band *sband;
struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);
- if (status->band < 0 ||
- status->band >= IEEE80211_NUM_BANDS) {
- WARN_ON(1);
- return;
- }
+ if (WARN_ON(status->band < 0 ||
+ status->band >= IEEE80211_NUM_BANDS))
+ goto drop;
sband = local->hw.wiphy->bands[status->band];
- if (!sband) {
- WARN_ON(1);
- return;
- }
+ if (WARN_ON(!sband))
+ goto drop;
/*
* If we're suspending, it is possible although not too likely
@@ -2466,25 +2462,21 @@
* that might, for example, cause stations to be added or other
* driver callbacks be invoked.
*/
- if (unlikely(local->quiescing || local->suspended)) {
- kfree_skb(skb);
- return;
- }
+ if (unlikely(local->quiescing || local->suspended))
+ goto drop;
/*
* The same happens when we're not even started,
* but that's worth a warning.
*/
- if (WARN_ON(!local->started)) {
- kfree_skb(skb);
- return;
- }
+ if (WARN_ON(!local->started))
+ goto drop;
if (status->flag & RX_FLAG_HT) {
/* rate_idx is MCS index */
if (WARN_ON(status->rate_idx < 0 ||
status->rate_idx >= 76))
- return;
+ goto drop;
/* HT rates are not in the table - use the highest legacy rate
* for now since other parts of mac80211 may not yet be fully
* MCS aware. */
@@ -2492,7 +2484,7 @@
} else {
if (WARN_ON(status->rate_idx < 0 ||
status->rate_idx >= sband->n_bitrates))
- return;
+ goto drop;
rate = &sband->bitrates[status->rate_idx];
}
@@ -2531,6 +2523,10 @@
__ieee80211_rx_handle_packet(hw, skb, rate);
rcu_read_unlock();
+
+ return;
+ drop:
+ kfree_skb(skb);
}
EXPORT_SYMBOL(ieee80211_rx);