package/kernel/mac80211/patches/351-mac80211-fix-tid-agg-null.patch

   1 From 1c3d185a9a0b136a58e73b02912d593d0303d1da Mon Sep 17 00:00:00 2001
   2 From: Johannes Berg <johannes.berg@intel.com>
   3 Date: Tue, 18 Oct 2016 23:12:08 +0300
   4 Subject: [PATCH] mac80211: fix tid_agg_rx NULL dereference
   5
   6 On drivers setting the SUPPORTS_REORDERING_BUFFER hardware flag,
   7 we crash when the peer sends an AddBA request while we already
   8 have a session open on the seame TID; this is because on those
   9 drivers, the tid_agg_rx is left NULL even though the session is
  10 valid, and the agg_session_valid bit is set.
  11
  12 To fix this, store the dialog tokens outside the tid_agg_rx to
  13 be able to compare them to the received AddBA request.
  14
  15 Fixes: f89e07d4cf26 ("mac80211: agg-rx: refuse ADDBA Request with timeout update")
  16 Reported-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
  17 Signed-off-by: Johannes Berg <johannes.berg@intel.com>
  18 ---
  19  net/mac80211/agg-rx.c      | 8 ++------
  20  net/mac80211/debugfs_sta.c | 2 +-
  21  net/mac80211/sta_info.h    | 4 ++--
  22  3 files changed, 5 insertions(+), 9 deletions(-)
  23
  24 --- a/net/mac80211/agg-rx.c
  25 +++ b/net/mac80211/agg-rx.c
  26 @@ -315,11 +315,7 @@ void __ieee80211_start_rx_ba_session(str
  27         mutex_lock(&sta->ampdu_mlme.mtx);
  28
  29         if (test_bit(tid, sta->ampdu_mlme.agg_session_valid)) {
  30 -               tid_agg_rx = rcu_dereference_protected(
  31 -                               sta->ampdu_mlme.tid_rx[tid],
  32 -                               lockdep_is_held(&sta->ampdu_mlme.mtx));
  33 -
  34 -               if (tid_agg_rx->dialog_token == dialog_token) {
  35 +               if (sta->ampdu_mlme.tid_rx_token[tid] == dialog_token) {
  36                         ht_dbg_ratelimited(sta->sdata,
  37                                            "updated AddBA Req from %pM on tid %u\n",
  38                                            sta->sta.addr, tid);
  39 @@ -396,7 +392,6 @@ void __ieee80211_start_rx_ba_session(str
  40         }
  41
  42         /* update data */
  43 -       tid_agg_rx->dialog_token = dialog_token;
  44         tid_agg_rx->ssn = start_seq_num;
  45         tid_agg_rx->head_seq_num = start_seq_num;
  46         tid_agg_rx->buf_size = buf_size;
  47 @@ -418,6 +413,7 @@ end:
  48         if (status == WLAN_STATUS_SUCCESS) {
  49                 __set_bit(tid, sta->ampdu_mlme.agg_session_valid);
  50                 __clear_bit(tid, sta->ampdu_mlme.unexpected_agg);
  51 +               sta->ampdu_mlme.tid_rx_token[tid] = dialog_token;
  52         }
  53         mutex_unlock(&sta->ampdu_mlme.mtx);
  54
  55 --- a/net/mac80211/debugfs_sta.c
  56 +++ b/net/mac80211/debugfs_sta.c
  57 @@ -205,7 +205,7 @@ static ssize_t sta_agg_status_read(struc
  58                 p += scnprintf(p, sizeof(buf) + buf - p, "%02d", i);
  59                 p += scnprintf(p, sizeof(buf) + buf - p, "\t\t%x", !!tid_rx);
  60                 p += scnprintf(p, sizeof(buf) + buf - p, "\t%#.2x",
  61 -                               tid_rx ? tid_rx->dialog_token : 0);
  62 +                               tid_rx ? sta->ampdu_mlme.tid_rx_token[i] : 0);
  63                 p += scnprintf(p, sizeof(buf) + buf - p, "\t%#.3x",
  64                                 tid_rx ? tid_rx->ssn : 0);
  65
  66 --- a/net/mac80211/sta_info.h
  67 +++ b/net/mac80211/sta_info.h
  68 @@ -184,7 +184,6 @@ struct tid_ampdu_tx {
  69   * @ssn: Starting Sequence Number expected to be aggregated.
  70   * @buf_size: buffer size for incoming A-MPDUs
  71   * @timeout: reset timer value (in TUs).
  72 - * @dialog_token: dialog token for aggregation session
  73   * @rcu_head: RCU head used for freeing this struct
  74   * @reorder_lock: serializes access to reorder buffer, see below.
  75   * @auto_seq: used for offloaded BA sessions to automatically pick head_seq_and
  76 @@ -213,7 +212,6 @@ struct tid_ampdu_rx {
  77         u16 ssn;
  78         u16 buf_size;
  79         u16 timeout;
  80 -       u8 dialog_token;
  81         bool auto_seq;
  82         bool removed;
  83  };
  84 @@ -225,6 +223,7 @@ struct tid_ampdu_rx {
  85   *     to tid_tx[idx], which are protected by the sta spinlock)
  86   *     tid_start_tx is also protected by sta->lock.
  87   * @tid_rx: aggregation info for Rx per TID -- RCU protected
  88 + * @tid_rx_token: dialog tokens for valid aggregation sessions
  89   * @tid_rx_timer_expired: bitmap indicating on which TIDs the
  90   *     RX timer expired until the work for it runs
  91   * @tid_rx_stop_requested:  bitmap indicating which BA sessions per TID the
  92 @@ -243,6 +242,7 @@ struct sta_ampdu_mlme {
  93         struct mutex mtx;
  94         /* rx */
  95         struct tid_ampdu_rx __rcu *tid_rx[IEEE80211_NUM_TIDS];
  96 +       u8 tid_rx_token[IEEE80211_NUM_TIDS];
  97         unsigned long tid_rx_timer_expired[BITS_TO_LONGS(IEEE80211_NUM_TIDS)];
  98         unsigned long tid_rx_stop_requested[BITS_TO_LONGS(IEEE80211_NUM_TIDS)];
  99         unsigned long agg_session_valid[BITS_TO_LONGS(IEEE80211_NUM_TIDS)];