Re: [PATCH] mac80211: drop data frames without key on encrypted links

[Greg KH <greg@kroah.com>]

On Mon, Aug 16, 2021 at 03:44:24PM +0200, Pali Rohár wrote:
> From: Johannes Berg <johannes.berg@intel.com>
> 
> 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 <j@w1.fi>
> Signed-off-by: Johannes Berg <johannes.berg@intel.com>
> Signed-off-by: Luca Coelho <luciano.coelho@intel.com>
> Link: https://lore.kernel.org/r/iwlwifi.20200326150855.6865c7f28a14.I9fb1d911b064262d33e33dfba730cdeef83926ca@changeid
> Signed-off-by: Johannes Berg <johannes.berg@intel.com>
> [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