[PATCH 3.2 056/152] mac80211: fix multicast LED blinking and counter

Ben Hutchings
2015-02-17T01:46:53Z

From: Andreas Müller <goo@stapelspeicher.org>

commit d025933e29872cb1fe19fc54d80e4dfa4ee5779c upstream.

As multicast-frames can't be fragmented, "dot11MulticastReceivedFrameCount"
stopped being incremented after the use-after-free fix. Furthermore, the
RX-LED will be triggered by every multicast frame (which wouldn't happen
before) which wouldn't allow the LED to rest at all.

Fixes https://bugzilla.kernel.org/show_bug.cgi?id=89431 which also had the
patch.

Fixes: b8fff407a180 ("mac80211: fix use-after-free in defragmentation")
Signed-off-by: Andreas Müller <goo@stapelspeicher.org>
[rewrite commit message]
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
---
net/mac80211/rx.c | 11 ++++++-----
1 file changed, 6 insertions(+), 5 deletions(-)

--- a/net/mac80211/rx.c
+++ b/net/mac80211/rx.c
@@ -1470,14 +1470,14 @@ ieee80211_rx_h_defragment(struct ieee802
sc = le16_to_cpu(hdr->seq_ctrl);
frag = sc & IEEE80211_SCTL_FRAG;

- if (likely(!ieee80211_has_morefrags(fc) && frag == 0))
- goto out;
-
if (is_multicast_ether_addr(hdr->addr1)) {
rx->local->dot11MulticastReceivedFrameCount++;
- goto out;
+ goto out_no_led;
}

+ if (likely(!ieee80211_has_morefrags(fc) && frag == 0))
+ goto out;
+
I802_DEBUG_INC(rx->local->rx_handlers_fragments);

if (skb_linearize(rx->skb))
@@ -1568,9 +1568,10 @@ ieee80211_rx_h_defragment(struct ieee802
status->rx_flags |= IEEE80211_RX_FRAGMENTED;

out:
+ ieee80211_led_rx(rx->local);
+ out_no_led:
if (rx->sta)
rx->sta->rx_packets++;
- ieee80211_led_rx(rx->local);
return RX_CONTINUE;
}