[PATCH 6.12 146/265] wifi: mac80211: bounds-check link_id in ieee80211_ml_reconfiguration

Greg Kroah-Hartman
2026-03-12T20:21:05Z

From: Ariel Silver <arielsilver77@gmail.com>

commit 162d331d833dc73a3e905a24c44dd33732af1fc5 upstream.

link_id is taken from the ML Reconfiguration element (control & 0x000f),
so it can be 0..15. link_removal_timeout[] has IEEE80211_MLD_MAX_NUM_LINKS
(15) elements, so index 15 is out-of-bounds. Skip subelements with
link_id >= IEEE80211_MLD_MAX_NUM_LINKS to avoid a stack out-of-bounds
write.

Fixes: 8eb8dd2ffbbb ("wifi: mac80211: Support link removal using Reconfiguration ML element")
Reported-by: Ariel Silver <arielsilver77@gmail.com>
Signed-off-by: Ariel Silver <arielsilver77@gmail.com>
Cc: stable@vger.kernel.org
Link: https://patch.msgid.link/20260220101129.1202657-1-Ariel.Silver@cybereason.com
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
net/mac80211/mlme.c | 3 +++
1 file changed, 3 insertions(+)

--- a/net/mac80211/mlme.c
+++ b/net/mac80211/mlme.c
@@ -6256,6 +6256,9 @@ static void ieee80211_ml_reconfiguration
control = le16_to_cpu(prof->control);
link_id = control & IEEE80211_MLE_STA_RECONF_CONTROL_LINK_ID;

+ if (link_id >= IEEE80211_MLD_MAX_NUM_LINKS)
+ continue;
+
removed_links |= BIT(link_id);

/* the MAC address should not be included, but handle it */