[PATCH 6.0 241/862] wifi: mac80211: mlme: dont add empty EML capabilities

From: Greg Kroah-Hartman
Date: Wed Oct 19 2022 - 09:59:38 EST


From: Mordechay Goodstein <mordechay.goodstein@xxxxxxxxx>

[ Upstream commit 1cb3cf372abe4a0d16620d2b1201de0e291a6c58 ]

Draft P802.11be_D2.1, section 35.3.17 states that the EML Capabilities
Field shouldn't be included in case the device doesn't have support for
EMLSR or EMLMR.

Fixes: 81151ce462e5 ("wifi: mac80211: support MLO authentication/association with one link")
Signed-off-by: Mordechay Goodstein <mordechay.goodstein@xxxxxxxxx>
Signed-off-by: Johannes Berg <johannes.berg@xxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
net/mac80211/mlme.c | 13 ++++++++++---
1 file changed, 10 insertions(+), 3 deletions(-)

diff --git a/net/mac80211/mlme.c b/net/mac80211/mlme.c
index 1e9cb4be6ed3..76ae6f03d77e 100644
--- a/net/mac80211/mlme.c
+++ b/net/mac80211/mlme.c
@@ -1220,14 +1220,21 @@ static void ieee80211_assoc_add_ml_elem(struct ieee80211_sub_if_data *sdata,
ml_elem = skb_put(skb, sizeof(*ml_elem));
ml_elem->control =
cpu_to_le16(IEEE80211_ML_CONTROL_TYPE_BASIC |
- IEEE80211_MLC_BASIC_PRES_EML_CAPA |
IEEE80211_MLC_BASIC_PRES_MLD_CAPA_OP);
common = skb_put(skb, sizeof(*common));
common->len = sizeof(*common) +
- 2 + /* EML capabilities */
2; /* MLD capa/ops */
memcpy(common->mld_mac_addr, sdata->vif.addr, ETH_ALEN);
- skb_put_data(skb, &eml_capa, sizeof(eml_capa));
+
+ /* add EML_CAPA only if needed, see Draft P802.11be_D2.1, 35.3.17 */
+ if (eml_capa &
+ cpu_to_le16((IEEE80211_EML_CAP_EMLSR_SUPP |
+ IEEE80211_EML_CAP_EMLMR_SUPPORT))) {
+ common->len += 2; /* EML capabilities */
+ ml_elem->control |=
+ cpu_to_le16(IEEE80211_MLC_BASIC_PRES_EML_CAPA);
+ skb_put_data(skb, &eml_capa, sizeof(eml_capa));
+ }
/* need indication from userspace to support this */
mld_capa_ops &= ~cpu_to_le16(IEEE80211_MLD_CAP_OP_TID_TO_LINK_MAP_NEG_SUPP);
skb_put_data(skb, &mld_capa_ops, sizeof(mld_capa_ops));
--
2.35.1