wifi: mt76: reject out-of-range link ids in mt76_vif_link()

mt76_vif_link() indexes mvif->link[] without validating link_id, but
callers pass mvif->deflink_id / msta->deflink_id, which hold
IEEE80211_LINK_UNSPECIFIED (0xf) until the first link has been added.
Since IEEE80211_MLD_MAX_NUM_LINKS is 15, that reads one element past the
end of the array, aliasing mt76_vif_data.offchannel_link.

Reachable via mt7996_set_tsf()/mt7996_offset_tsf() and
mt7996_net_fill_forward_path(). Bounds check link_id and return NULL,
matching mt7996_sta_link() and mt7996_sta_link_protected().

Fixes: a9384b36a42a ("wifi: mt76: mt7996: rework set/get_tsf callabcks to support MLO")
Link: https://patch.msgid.link/20260801145334.1166751-9-nbd@nbd.name
Signed-off-by: Felix Fietkau <nbd@nbd.name>

0 files changed, 0 insertions, 0 deletions