diff options
| author | Felix Fietkau <nbd@nbd.name> | 2026-03-05 20:08:12 +0300 |
|---|---|---|
| committer | Johannes Berg <johannes.berg@intel.com> | 2026-03-06 13:08:43 +0300 |
| commit | 672e5229e1ecfc2a3509b53adcb914d8b024a853 (patch) | |
| tree | 5a4ad76077950da0ccbb19ef8626770e2ebcaf01 | |
| parent | ac6f24cc9c0a9aefa55ec9696dcafa971d4d760b (diff) | |
| download | linux-672e5229e1ecfc2a3509b53adcb914d8b024a853.tar.xz | |
mac80211: fix crash in ieee80211_chan_bw_change for AP_VLAN stations
ieee80211_chan_bw_change() iterates all stations and accesses
link->reserved.oper via sta->sdata->link[link_id]. For stations on
AP_VLAN interfaces (e.g. 4addr WDS clients), sta->sdata points to
the VLAN sdata, whose link never participates in chanctx reservations.
This leaves link->reserved.oper zero-initialized with chan == NULL,
causing a NULL pointer dereference in __ieee80211_sta_cap_rx_bw()
when accessing chandef->chan->band during CSA.
Resolve the VLAN sdata to its parent AP sdata using get_bss_sdata()
before accessing link data.
Cc: stable@vger.kernel.org
Signed-off-by: Felix Fietkau <nbd@nbd.name>
Link: https://patch.msgid.link/20260305170812.2904208-1-nbd@nbd.name
[also change sta->sdata in ARRAY_SIZE even if it doesn't matter]
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
| -rw-r--r-- | net/mac80211/chan.c | 6 |
1 files changed, 4 insertions, 2 deletions
diff --git a/net/mac80211/chan.c b/net/mac80211/chan.c index 4447cf03c41b..05f45e66999b 100644 --- a/net/mac80211/chan.c +++ b/net/mac80211/chan.c @@ -561,14 +561,16 @@ static void ieee80211_chan_bw_change(struct ieee80211_local *local, rcu_read_lock(); list_for_each_entry_rcu(sta, &local->sta_list, list) { - struct ieee80211_sub_if_data *sdata = sta->sdata; + struct ieee80211_sub_if_data *sdata; enum ieee80211_sta_rx_bandwidth new_sta_bw; unsigned int link_id; if (!ieee80211_sdata_running(sta->sdata)) continue; - for (link_id = 0; link_id < ARRAY_SIZE(sta->sdata->link); link_id++) { + sdata = get_bss_sdata(sta->sdata); + + for (link_id = 0; link_id < ARRAY_SIZE(sdata->link); link_id++) { struct ieee80211_link_data *link = rcu_dereference(sdata->link[link_id]); struct ieee80211_bss_conf *link_conf; |