wifi: mac80211: bounds-check link_id in ieee80211_ml_reconfiguration

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>

diff --git a/net/mac80211/mlme.c b/net/mac80211/mlme.c
index e83582b2c37722dd8cb555ab432966afa436bafa..d43204ee330eb8f96fde1bfcc297397fe4e55442 100644 (file)
--- a/net/mac80211/mlme.c
+++ b/net/mac80211/mlme.c
@@ -7085,6 +7085,9 @@ static void ieee80211_ml_reconfiguration(struct ieee80211_sub_if_data *sdata,
                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 */