releases/4.6.5/mac80211-fix-fast_tx-header-alignment.patch

   1 From 6fe04128f158c5ad27e7504bfdf1b12e63331bc9 Mon Sep 17 00:00:00 2001
   2 From: Felix Fietkau <nbd@nbd.name>
   3 Date: Thu, 19 May 2016 17:34:38 +0200
   4 Subject: mac80211: fix fast_tx header alignment
   5
   6 From: Felix Fietkau <nbd@nbd.name>
   7
   8 commit 6fe04128f158c5ad27e7504bfdf1b12e63331bc9 upstream.
   9
  10 The header field is defined as u8[] but also accessed as struct
  11 ieee80211_hdr. Enforce an alignment of 2 to prevent unnecessary
  12 unaligned accesses, which can be very harmful for performance on many
  13 platforms.
  14
  15 Fixes: e495c24731a2 ("mac80211: extend fast-xmit for more ciphers")
  16 Signed-off-by: Felix Fietkau <nbd@nbd.name>
  17 Signed-off-by: Johannes Berg <johannes.berg@intel.com>
  18 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
  19
  20 ---
  21  net/mac80211/sta_info.h |    2 +-
  22  1 file changed, 1 insertion(+), 1 deletion(-)
  23
  24 --- a/net/mac80211/sta_info.h
  25 +++ b/net/mac80211/sta_info.h
  26 @@ -275,7 +275,7 @@ struct ieee80211_fast_tx {
  27         u8 sa_offs, da_offs, pn_offs;
  28         u8 band;
  29         u8 hdr[30 + 2 + IEEE80211_FAST_XMIT_MAX_IV +
  30 -              sizeof(rfc1042_header)];
  31 +              sizeof(rfc1042_header)] __aligned(2);
  32
  33         struct rcu_head rcu_head;
  34  };