mac80211: fix crash in ieee80211_chan_bw_change for AP_VLAN stations

Browse source

commit 672e5229e1 upstream.

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>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

...

This commit is contained in:

Felix Fietkau 2026-03-05 17:08:12 +00:00 • committed by Greg Kroah-Hartman

parent 0e35db29fc

commit 5a86d4e920

1 changed files with 4 additions and 2 deletions

Show all changes Ignore whitespace when comparing lines Ignore changes in amount of whitespace Ignore changes in whitespace at EOL

Download patch file Download diff file Expand all files Collapse all files

6

net/mac80211/chan.c

View file