This is a note to let you know that I've just added the patch titled
wifi: mac80211: fix RCU use in TDLS fast-xmit
to the 6.7-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
wifi-mac80211-fix-rcu-use-in-tdls-fast-xmit.patch
and it can be found in the queue-6.7 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit 2d04941fcb286734bdb615c66e211572e458837d
Author: Johannes Berg <johannes.berg@xxxxxxxxx>
Date: Mon Jan 29 15:53:48 2024 +0100
wifi: mac80211: fix RCU use in TDLS fast-xmit
[ Upstream commit 9480adfe4e0f0319b9da04b44e4eebd5ad07e0cd ]
This looks up the link under RCU protection, but isn't
guaranteed to actually have protection. Fix that.
Fixes: 8cc07265b691 ("wifi: mac80211: handle TDLS data frames with MLO")
Link: https://msgid.link/20240129155348.8a9c0b1e1d89.I553f96ce953bb41b0b877d592056164dec20d01c@changeid
Signed-off-by: Johannes Berg <johannes.berg@xxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/net/mac80211/tx.c b/net/mac80211/tx.c
index ed4fdf655343..a94feb6b579b 100644
--- a/net/mac80211/tx.c
+++ b/net/mac80211/tx.c
@@ -3100,10 +3100,11 @@ void ieee80211_check_fast_xmit(struct sta_info *sta)
/* DA SA BSSID */
build.da_offs = offsetof(struct ieee80211_hdr, addr1);
build.sa_offs = offsetof(struct ieee80211_hdr, addr2);
+ rcu_read_lock();
link = rcu_dereference(sdata->link[tdls_link_id]);
- if (WARN_ON_ONCE(!link))
- break;
- memcpy(hdr->addr3, link->u.mgd.bssid, ETH_ALEN);
+ if (!WARN_ON_ONCE(!link))
+ memcpy(hdr->addr3, link->u.mgd.bssid, ETH_ALEN);
+ rcu_read_unlock();
build.hdr_len = 24;
break;
}
