mac80211: fix receiving mesh packets in forwarding=0 networks

When forwarding is set to 0, frames are typically sent with ttl=1.
Move the ttl decrement check below the check for local receive in order to
fix packet drops.

Signed-off-by: Felix Fietkau <[email protected]>

package/kernel/mac80211/patches/subsys/329-wifi-mac80211-fix-receiving-mesh-packets-in-forwardi.patch

@@ -0,0 +1,50 @@
+From: Felix Fietkau <[email protected]>
+Date: Sun, 26 Mar 2023 17:11:34 +0200
+Subject: [PATCH] wifi: mac80211: fix receiving mesh packets in forwarding=0
+ networks
+MIME-Version: 1.0
+Content-Type: text/plain; charset=UTF-8
+Content-Transfer-Encoding: 8bit
+
+When forwarding is set to 0, frames are typically sent with ttl=1.
+Move the ttl decrement check below the check for local receive in order to
+fix packet drops.
+
+Reported-by: Thomas Hühn <[email protected]>
+Reported-by: Nick Hainke <[email protected]>
+Fixes: 986e43b19ae9 ("wifi: mac80211: fix receiving A-MSDU frames on mesh interfaces")
+Signed-off-by: Felix Fietkau <[email protected]>
+---
+
+--- a/net/mac80211/rx.c
++++ b/net/mac80211/rx.c
+@@ -2828,14 +2828,6 @@ ieee80211_rx_mesh_data(struct ieee80211_
+ 	if (sdata->crypto_tx_tailroom_needed_cnt)
+ 		tailroom = IEEE80211_ENCRYPT_TAILROOM;
+ 
+-	if (!--mesh_hdr->ttl) {
+-		if (multicast)
+-			goto rx_accept;
+-
+-		IEEE80211_IFSTA_MESH_CTR_INC(ifmsh, dropped_frames_ttl);
+-		return RX_DROP_MONITOR;
+-	}
+-
+ 	if (mesh_hdr->flags & MESH_FLAGS_AE) {
+ 		struct mesh_path *mppath;
+ 		char *proxied_addr;
+@@ -2874,6 +2866,14 @@ ieee80211_rx_mesh_data(struct ieee80211_
+ 	if (ether_addr_equal(sdata->vif.addr, eth->h_dest))
+ 		goto rx_accept;
+ 
++	if (!--mesh_hdr->ttl) {
++		if (multicast)
++			goto rx_accept;
++
++		IEEE80211_IFSTA_MESH_CTR_INC(ifmsh, dropped_frames_ttl);
++		return RX_DROP_MONITOR;
++	}
++
+ 	if (!ifmsh->mshcfg.dot11MeshForwarding) {
+ 		if (is_multicast_ether_addr(eth->h_dest))
+ 			goto rx_accept;