mac80211: fix a corner case in encapsulation offload support

Fix encryption key selection with WEP

Signed-off-by: Felix Fietkau <nbd@nbd.name>

diff --git a/package/kernel/mac80211/patches/subsys/313-mac80211-fix-encryption-key-selection-for-802.3-xmit.patch b/package/kernel/mac80211/patches/subsys/313-mac80211-fix-encryption-key-selection-for-802.3-xmit.patch
new file mode 100644 (file)
index 0000000..5ae9ca8
--- /dev/null
+++ b/package/kernel/mac80211/patches/subsys/313-mac80211-fix-encryption-key-selection-for-802.3-xmit.patch
@@ -0,0 +1,53 @@
+From: Felix Fietkau <nbd@nbd.name>
+Date: Wed, 16 Dec 2020 21:23:24 +0100
+Subject: [PATCH] mac80211: fix encryption key selection for 802.3 xmit
+
+When using WEP, the default unicast key needs to be selected, instead of
+the STA PTK.
+
+Signed-off-by: Felix Fietkau <nbd@nbd.name>
+---
+
+--- a/net/mac80211/tx.c
++++ b/net/mac80211/tx.c
+@@ -4262,7 +4262,6 @@ netdev_tx_t ieee80211_subif_start_xmit_8
+       struct ethhdr *ehdr = (struct ethhdr *)skb->data;
+       struct ieee80211_key *key;
+       struct sta_info *sta;
+-      bool offload = true;
+ 
+       if (unlikely(skb->len < ETH_HLEN)) {
+               kfree_skb(skb);
+@@ -4278,18 +4277,22 @@ netdev_tx_t ieee80211_subif_start_xmit_8
+ 
+       if (unlikely(IS_ERR_OR_NULL(sta) || !sta->uploaded ||
+           !test_sta_flag(sta, WLAN_STA_AUTHORIZED) ||
+-              sdata->control_port_protocol == ehdr->h_proto))
+-              offload = false;
+-      else if ((key = rcu_dereference(sta->ptk[sta->ptk_idx])) &&
+-               (!(key->flags & KEY_FLAG_UPLOADED_TO_HARDWARE) ||
+-                key->conf.cipher == WLAN_CIPHER_SUITE_TKIP))
+-              offload = false;
++          sdata->control_port_protocol == ehdr->h_proto))
++              goto skip_offload;
+ 
+-      if (offload)
+-              ieee80211_8023_xmit(sdata, dev, sta, key, skb);
+-      else
+-              ieee80211_subif_start_xmit(skb, dev);
++      key = rcu_dereference(sta->ptk[sta->ptk_idx]);
++      if (!key)
++              key = rcu_dereference(sdata->default_unicast_key);
++
++      if (key && (!(key->flags & KEY_FLAG_UPLOADED_TO_HARDWARE) ||
++                  key->conf.cipher == WLAN_CIPHER_SUITE_TKIP))
++              goto skip_offload;
++
++      ieee80211_8023_xmit(sdata, dev, sta, key, skb);
++      goto out;
+ 
++skip_offload:
++      ieee80211_subif_start_xmit(skb, dev);
+ out:
+       rcu_read_unlock();
+