From: Felix Fietkau Date: Fri, 31 Jul 2015 19:49:17 +0000 (+0000) Subject: mac80211: fix an invalid read in minstrel rate sorting X-Git-Tag: reboot~2352 X-Git-Url: http://git.lede-project.org./?a=commitdiff_plain;h=ad5cd9ec1df33c9b700c904f99dfc5b30b481ab0;p=openwrt%2Fopenwrt.git mac80211: fix an invalid read in minstrel rate sorting Signed-off-by: Felix Fietkau SVN-Revision: 46533 --- diff --git a/package/kernel/mac80211/patches/310-mac80211-fix-invalid-read-in-minstrel_sort_best_tp_r.patch b/package/kernel/mac80211/patches/310-mac80211-fix-invalid-read-in-minstrel_sort_best_tp_r.patch new file mode 100644 index 0000000000..51a315c204 --- /dev/null +++ b/package/kernel/mac80211/patches/310-mac80211-fix-invalid-read-in-minstrel_sort_best_tp_r.patch @@ -0,0 +1,34 @@ +From: Adrien Schildknecht +Date: Tue, 28 Jul 2015 10:30:16 +0200 +Subject: [PATCH] mac80211: fix invalid read in minstrel_sort_best_tp_rates() + +At the last iteration of the loop, j may equal zero and thus +tp_list[j - 1] causes an invalid read. +Changed the logic of the loop so that j - 1 is always >= 0. + +Signed-off-by: Adrien Schildknecht +--- + +--- 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)