lkml.org 
[lkml]   [2015]   [Sep]   [11]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    Patch in this message
    /
    From
    Subject[PATCH 4.1 55/78] mac80211: fix invalid read in minstrel_sort_best_tp_rates()
    Date
    4.1-stable review patch.  If anyone has any objections, please let me know.

    ------------------

    From: Adrien Schildknecht <adrien+dev@schischi.me>

    commit f5eeb5fa191fd7b634cbc4883ac58f3b2184dbc5 upstream.

    At the last iteration of the loop, j may equal zero and thus
    tp_list[j - 1] causes an invalid read.
    Change the logic of the loop so that j - 1 is always >= 0.

    Signed-off-by: Adrien Schildknecht <adrien+dev@schischi.me>
    Signed-off-by: Johannes Berg <johannes.berg@intel.com>
    Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

    ---
    net/mac80211/rc80211_minstrel.c | 11 ++++++-----
    1 file changed, 6 insertions(+), 5 deletions(-)

    --- a/net/mac80211/rc80211_minstrel.c
    +++ b/net/mac80211/rc80211_minstrel.c
    @@ -92,14 +92,15 @@ int minstrel_get_tp_avg(struct minstrel_
    static inline void
    minstrel_sort_best_tp_rates(struct minstrel_sta_info *mi, int i, u8 *tp_list)
    {
    - int j = MAX_THR_RATES;
    - struct minstrel_rate_stats *tmp_mrs = &mi->r[j - 1].stats;
    + int j;
    + struct minstrel_rate_stats *tmp_mrs;
    struct minstrel_rate_stats *cur_mrs = &mi->r[i].stats;

    - while (j > 0 && (minstrel_get_tp_avg(&mi->r[i], cur_mrs->prob_ewma) >
    - minstrel_get_tp_avg(&mi->r[tp_list[j - 1]], tmp_mrs->prob_ewma))) {
    - j--;
    + for (j = MAX_THR_RATES; j > 0; --j) {
    tmp_mrs = &mi->r[tp_list[j - 1]].stats;
    + if (minstrel_get_tp_avg(&mi->r[i], cur_mrs->prob_ewma) <=
    + minstrel_get_tp_avg(&mi->r[tp_list[j - 1]], tmp_mrs->prob_ewma))
    + break;
    }

    if (j < MAX_THR_RATES - 1)



    \
     
     \ /
      Last update: 2015-09-12 01:01    [W:2.374 / U:0.116 seconds]
    ©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site