tree 687deeae1daaa4be04fb1a1644b5d587c62acafa
parent 83374fe9de455e37c2a039603d2538eb77e8ec4d
author Johannes Berg <johannes.berg@intel.com> 1373574806 +0200
committer Johannes Berg <johannes.berg@intel.com> 1373957759 +0300

mac80211: fix duplicate retransmission detection

The duplicate retransmission detection code in mac80211
erroneously attempts to do the check for every frame,
even frames that don't have a sequence control field or
that don't use it (QoS-Null frames.)

This is problematic because it causes the code to access
data beyond the end of the SKB and depending on the data
there will drop packets erroneously.

Correct the code to not do duplicate detection for such
frames.

I found this error while testing AP powersave, it lead
to retransmitted PS-Poll frames being dropped entirely
as the data beyond the end of the SKB was always zero.

Cc: stable@vger.kernel.org [all versions]
Signed-off-by: Johannes Berg <johannes.berg@intel.com>