Commit eb3e554b authored Jan 24, 2011 by Felix Fietkau Committed by John W. Linville Jan 25, 2011

mac80211: fix a crash in ieee80211_beacon_get_tim on change_interface



Some drivers (e.g. ath9k) do not always disable beacons when they're
supposed to. When an interface is changed using the change_interface op,
the mode specific sdata part is in an undefined state and trying to
get a beacon at this point can produce weird crashes.

To fix this, add a check for ieee80211_sdata_running before using
anything from the sdata.

Signed-off-by: Felix Fietkau <nbd@openwrt.org>
Cc: stable@kernel.org
Signed-off-by: John W. Linville <linville@tuxdriver.com>

parent bdc4bf65

net/mac80211/tx.c

+3 −0

Original line number	Diff line number	Diff line
		@@ -2230,6 +2230,9 @@ struct sk_buff ieee80211_beacon_get_tim(struct ieee80211_hw hw,

		sdata = vif_to_sdata(vif);

		if (!ieee80211_sdata_running(sdata))
		goto out;

		if (tim_offset)
		*tim_offset = 0;
		if (tim_length)