@@ -248,6 +248,7 @@ static void ieee80211_restart_work(struct work_struct *work)
{
struct ieee80211_local *local =
container_of(work, struct ieee80211_local, restart_work);
+ struct ieee80211_sub_if_data *sdata;
/* wait for scan work complete */
flush_workqueue(local->workqueue);
@@ -256,6 +257,8 @@ static void ieee80211_restart_work(struct work_struct *work)
"%s called with hardware scan in progress\n", __func__);
rtnl_lock();
+ list_for_each_entry(sdata, &local->interfaces, list)
+ flush_delayed_work(&sdata->dec_tailroom_needed_wk);
ieee80211_scan_cancel(local);
ieee80211_reconfig(local);
rtnl_unlock();
This is a note to let you know that I have just added a patch titled mac80211: prevent possible crypto tx tailroom corruption to the linux-3.16.y-queue branch of the 3.16.y-ckt extended stable tree which can be found at: http://kernel.ubuntu.com/git/ubuntu/linux.git/log/?h=linux-3.16.y-queue This patch is scheduled to be released in version 3.16.7-ckt15. If you, or anyone else, feels it should not be added to this tree, please reply to this email. For more information about the 3.16.y-ckt tree, see https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable Thanks. -Luis ------ From b9132b089d13ebbb5e067d5645761274e3a5cd63 Mon Sep 17 00:00:00 2001 From: Michal Kazior <michal.kazior@tieto.com> Date: Fri, 22 May 2015 10:22:40 +0200 Subject: mac80211: prevent possible crypto tx tailroom corruption commit ab499db80fcf07c18e4053f91a619500f663e90e upstream. There was a possible race between ieee80211_reconfig() and ieee80211_delayed_tailroom_dec(). This could result in inability to transmit data if driver crashed during roaming or rekeying and subsequent skbs with insufficient tailroom appeared. This race was probably never seen in the wild because a device driver would have to crash AND recover within 0.5s which is very unlikely. I was able to prove this race exists after changing the delay to 10s locally and crashing ath10k via debugfs immediately after GTK rekeying. In case of ath10k the counter went below 0. This was harmless but other drivers which actually require tailroom (e.g. for WEP ICV or MMIC) could end up with the counter at 0 instead of >0 and introduce insufficient skb tailroom failures because mac80211 would not resize skbs appropriately anymore. Fixes: 8d1f7ecd2af5 ("mac80211: defer tailroom counter manipulation when roaming") Signed-off-by: Michal Kazior <michal.kazior@tieto.com> Signed-off-by: Johannes Berg <johannes.berg@intel.com> Signed-off-by: Luis Henriques <luis.henriques@canonical.com> --- net/mac80211/main.c | 3 +++ 1 file changed, 3 insertions(+)