mac80211: set basic-rate to lowest of band

To keep compatibility, mesh settigns have to match the previous default.

In order to do so, set the mesh basic-rate to the lowest rate of the
frequency band.

Signed-off-by: David Bauer <mail@david-bauer.net>

patches/openwrt/0008-net-mac80211-always-pretend-1-Mbit-s-as-mesh-basic-rate.patch → patches/openwrt/0008-net-mac80211-always-pretend-lowest-rate-as-mesh-basic-rate.patch

@@ -1,19 +1,20 @@
 From: David Bauer <mail@david-bauer.net>
 Date: Tue, 7 Jan 2025 00:49:41 +0100
-Subject: net: mac80211: always pretend 1 Mbit/s as mesh basic rate
+Subject: net: mac80211: always pretend lowest rate as mesh basic rate
 
-In order to be backwards-compatible, pretend to have 1 Mbit/s 802.11b as
-basic rate regardless of the actual setting. This is required to keep
-compatibility with other non-patched mesh neighbors.
+In order to be backwards-compatible, pretend to have the lowest
+basic-rate of the band  as basic rate regardless of the actual
+setting. This is required to keep compatibility with other
+non-patched mesh neighbors.
 
 Signed-off-by: David Bauer <mail@david-bauer.net>
 
 diff --git a/package/kernel/mac80211/patches/subsys/996-net-mac80211-always-pretend-1-Mbit-s-as-mesh-basic-r.patch b/package/kernel/mac80211/patches/subsys/996-net-mac80211-always-pretend-1-Mbit-s-as-mesh-basic-r.patch
 new file mode 100644
-index 0000000000000000000000000000000000000000..becb17317abb9782d4827a38c232b58939246ae1
+index 0000000000000000000000000000000000000000..730709ecb002e3696c0ec53dd5b8cfa48fe7a881
 --- /dev/null
 +++ b/package/kernel/mac80211/patches/subsys/996-net-mac80211-always-pretend-1-Mbit-s-as-mesh-basic-r.patch
-@@ -0,0 +1,44 @@
+@@ -0,0 +1,66 @@
 +From 70c1812fa170ee35cdc576c886bed4bfaae1d23c Mon Sep 17 00:00:00 2001
 +From: David Bauer <mail@david-bauer.net>
 +Date: Tue, 7 Jan 2025 00:47:33 +0100
@@ -30,31 +31,53 @@ index 0000000000000000000000000000000000000000..becb17317abb9782d4827a38c232b589
 +
 +--- a/net/mac80211/mesh.c
 ++++ b/net/mac80211/mesh.c
-+@@ -1093,7 +1093,7 @@ ieee80211_mesh_build_beacon(struct ieee8
++@@ -954,6 +954,7 @@ ieee80211_mesh_build_beacon(struct ieee8
++ 	struct ieee80211_sub_if_data *sdata;
++ 	int hdr_len = offsetofend(struct ieee80211_mgmt, u.beacon);
++ 	u32 rate_flags;
+++	u32 br_bitfield;
++ 
++ 	sdata = container_of(ifmsh, struct ieee80211_sub_if_data, u.mesh);
++ 
++@@ -1086,8 +1087,16 @@ ieee80211_mesh_build_beacon(struct ieee8
++ 	}
 + 	rcu_read_unlock();
 + 
+++	if (sband->band == IEEE80211_BAND_2GHZ) {
+++		br_bitfield = BIT(0);
+++	} else if (sband->band == IEEE80211_BAND_5GHZ) {
+++		br_bitfield = BIT(4);
+++	} else {
+++		br_bitfield = sdata->vif.bss_conf.basic_rates;
+++	}
+++
 + 	if (ieee80211_put_srates_elem(skb, sband,
 +-				      sdata->vif.bss_conf.basic_rates,
-++				      BIT(0),
+++				      br_bitfield,
 + 				      rate_flags, 0, WLAN_EID_SUPP_RATES) ||
 + 	    mesh_add_ds_params_ie(sdata, skb))
 + 		goto out_free;
-+@@ -1106,7 +1106,7 @@ ieee80211_mesh_build_beacon(struct ieee8
++@@ -1100,7 +1109,7 @@ ieee80211_mesh_build_beacon(struct ieee8
 + 	bcn->tail = bcn->head + bcn->head_len;
 + 
 + 	if (ieee80211_put_srates_elem(skb, sband,
 +-				      sdata->vif.bss_conf.basic_rates,
-++				      BIT(0),
+++				      br_bitfield,
 + 				      rate_flags, 0, WLAN_EID_EXT_SUPP_RATES) ||
 + 	    mesh_add_rsn_ie(sdata, skb) ||
 + 	    mesh_add_ht_cap_ie(sdata, skb) ||
 +--- a/net/mac80211/mesh_plink.c
 ++++ b/net/mac80211/mesh_plink.c
-+@@ -283,6 +283,7 @@ static int mesh_plink_frame_tx(struct ie
-+ 		rate_flags =
++@@ -284,6 +284,12 @@ static int mesh_plink_frame_tx(struct ie
 + 			ieee80211_chandef_rate_flags(&sdata->vif.bss_conf.chanreq.oper);
 + 		basic_rates = sdata->vif.bss_conf.basic_rates;
-++		basic_rates = BIT(0); /* mandatory rate */
 + 
+++		if (sband->band == IEEE80211_BAND_2GHZ) {
+++			basic_rates = BIT(0); /* mandatory rate */
+++		} else if (sband->band == IEEE80211_BAND_5GHZ) {
+++			basic_rates = BIT(4); /* mandatory rate */
+++		}
+++
 + 		if (ieee80211_put_srates_elem(skb, sband, basic_rates,
 + 					      rate_flags, 0,
++ 					      WLAN_EID_SUPP_RATES) ||