On Mon, Aug 16, 2021 at 03:44:24PM +0200, Pali Rohár wrote:

From: Johannes Berg <redacted>

commit a0761a301746ec2d92d7fcb82af69c0a6a4339aa upstream.

If we know that we have an encrypted link (based on having had
a key configured for TX in the past) then drop all data frames
in the key selection handler if there's no key anymore.

This fixes an issue with mac80211 internal TXQs - there we can
buffer frames for an encrypted link, but then if the key is no
longer there when they're dequeued, the frames are sent without
encryption. This happens if a station is disconnected while the
frames are still on the TXQ.

Detecting that a link should be encrypted based on a first key
having been configured for TX is fine as there are no use cases
for a connection going from with encryption to no encryption.
With extended key IDs, however, there is a case of having a key
configured for only decryption, so we can't just trigger this
behaviour on a key being configured.

Cc: stable@vger.kernel.org
Reported-by: Jouni Malinen <redacted>
Signed-off-by: Johannes Berg <redacted>
Signed-off-by: Luca Coelho <redacted>
Link: https://lore.kernel.org/r/iwlwifi.20200326150855.6865c7f28a14.I9fb1d911b064262d33e33dfba730cdeef83926ca@changeid (local)
Signed-off-by: Johannes Berg <redacted>
[pali: Backported to 4.19 and older versions]
Signed-off-by: Pali Rohár <pali@kernel.org>

Now queued up, thanks!

Did not apply to 4.4.y, don't know if you want it there or not...

thanks,

greg k-h