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 <[email protected]>
Cc: [email protected]
---
net/mac80211/tx.c | 3 +++
1 files changed, 3 insertions(+), 0 deletions(-)
diff --git a/net/mac80211/tx.c b/net/mac80211/tx.c
index e46c801..ffc6749 100644
--- a/net/mac80211/tx.c
+++ b/net/mac80211/tx.c
@@ -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)
--
1.7.3.2