This is a note to let you know that I've just added the patch titled mac80211: fix divide by zero when NOA update to the 4.1-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: mac80211-fix-divide-by-zero-when-noa-update.patch and it can be found in the queue-4.1 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. >From 519ee6918b91abdc4bc9720deae17599a109eb40 Mon Sep 17 00:00:00 2001 From: "Janusz.Dziedzic@xxxxxxxxx" <Janusz.Dziedzic@xxxxxxxxx> Date: Tue, 27 Oct 2015 08:35:11 +0100 Subject: mac80211: fix divide by zero when NOA update From: "Janusz.Dziedzic@xxxxxxxxx" <Janusz.Dziedzic@xxxxxxxxx> commit 519ee6918b91abdc4bc9720deae17599a109eb40 upstream. In case of one shot NOA the interval can be 0, catch that instead of potentially (depending on the driver) crashing like this: divide error: 0000 [#1] SMP [...] Call Trace: <IRQ> [<ffffffffc08e891c>] ieee80211_extend_absent_time+0x6c/0xb0 [mac80211] [<ffffffffc08e8a17>] ieee80211_update_p2p_noa+0xb7/0xe0 [mac80211] [<ffffffffc069cc30>] ath9k_p2p_ps_timer+0x170/0x190 [ath9k] [<ffffffffc070adf8>] ath_gen_timer_isr+0xc8/0xf0 [ath9k_hw] [<ffffffffc0691156>] ath9k_tasklet+0x296/0x2f0 [ath9k] [<ffffffff8107ad65>] tasklet_action+0xe5/0xf0 [...] Signed-off-by: Janusz Dziedzic <janusz.dziedzic@xxxxxxxxx> Signed-off-by: Johannes Berg <johannes.berg@xxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- net/mac80211/util.c | 7 +++++++ 1 file changed, 7 insertions(+) --- a/net/mac80211/util.c +++ b/net/mac80211/util.c @@ -2984,6 +2984,13 @@ ieee80211_extend_noa_desc(struct ieee802 if (end > 0) return false; + /* One shot NOA */ + if (data->count[i] == 1) + return false; + + if (data->desc[i].interval == 0) + return false; + /* End time is in the past, check for repetitions */ skip = DIV_ROUND_UP(-end, data->desc[i].interval); if (data->count[i] < 255) { Patches currently in stable-queue which might be from Janusz.Dziedzic@xxxxxxxxx are queue-4.1/mac80211-fix-divide-by-zero-when-noa-update.patch -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html