mac80211: move packet flags into packet

commit 8c0c709eea5cbab97fb464cd68b06f24acc58ee1
Author: Johannes Berg <johannes@sipsolutions.net>
Date:   Wed Nov 25 17:46:15 2009 +0100

    mac80211: move cmntr flag out of rx flags

moved the CMNTR flag into the skb RX flags for
some aggregation cleanups, but this was wrong
since the optimisation this flag tried to make
requires that it is kept across the processing
of multiple interfaces -- which isn't true for
flags in the skb. The patch not only broke the
optimisation, it also introduced a bug: under
some (common!) circumstances the flag will be
set on an already freed skb!

However, investigating this in more detail, I
found that most of the flags that we set should
be per packet, _except_ for this one, due to
a-MPDU processing. Additionally, the flags used
for processing (currently just this one) need
to be reset before processing a new packet.

Since we haven't actually seen bugs reported as
a result of the wrong flags handling (which is
not too surprising -- the only real bug case I
can come up with is an a-MSDU contained in an
a-MPDU), I'll make a different fix for rc.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

1 files changed, 31 insertions, 7 deletions

diff --git a/net/mac80211/ieee80211_i.h b/net/mac80211/ieee80211_i.h
index 40f747273389..945fbf29719d 100644
--- a/net/mac80211/ieee80211_i.h
+++ b/net/mac80211/ieee80211_i.h
@@ -159,13 +159,37 @@ typedef unsigned __bitwise__ ieee80211_rx_result;
 #define RX_DROP_MONITOR         ((__force ieee80211_rx_result) 2u)
 #define RX_QUEUED               ((__force ieee80211_rx_result) 3u)
 
-#define IEEE80211_RX_IN_SCAN            BIT(0)
-/* frame is destined to interface currently processed (incl. multicast frames) */
-#define IEEE80211_RX_RA_MATCH           BIT(1)
-#define IEEE80211_RX_AMSDU              BIT(2)
-#define IEEE80211_RX_FRAGMENTED         BIT(3)
-#define IEEE80211_MALFORMED_ACTION_FRM  BIT(4)
-/* only add flags here that do not change with subframes of an aMPDU */
+/**
+ * enum ieee80211_packet_rx_flags - packet RX flags
+ * @IEEE80211_RX_RA_MATCH: frame is destined to interface currently processed
+ *      (incl. multicast frames)
+ * @IEEE80211_RX_IN_SCAN: received while scanning
+ * @IEEE80211_RX_FRAGMENTED: fragmented frame
+ * @IEEE80211_RX_AMSDU: a-MSDU packet
+ * @IEEE80211_RX_MALFORMED_ACTION_FRM: action frame is malformed
+ *
+ * These are per-frame flags that are attached to a frame in the
+ * @rx_flags field of &struct ieee80211_rx_status.
+ */
+enum ieee80211_packet_rx_flags {
+        IEEE80211_RX_IN_SCAN                    = BIT(0),
+        IEEE80211_RX_RA_MATCH                   = BIT(1),
+        IEEE80211_RX_FRAGMENTED                 = BIT(2),
+        IEEE80211_RX_AMSDU                      = BIT(3),
+        IEEE80211_RX_MALFORMED_ACTION_FRM       = BIT(4),
+};
+
+/**
+ * enum ieee80211_rx_flags - RX data flags
+ *
+ * @IEEE80211_RX_CMNTR: received on cooked monitor already
+ *
+ * These flags are used across handling multiple interfaces
+ * for a single frame.
+ */
+enum ieee80211_rx_flags {
+        IEEE80211_RX_CMNTR              = BIT(0),
+};
 
 struct ieee80211_rx_data {
         struct sk_buff *skb;