treewide: Use fallthrough pseudo-keyword

[mirror_ubuntu-jammy-kernel.git] / drivers / net / wan / x25_asy.c

diff --git a/drivers/net/wan/x25_asy.c b/drivers/net/wan/x25_asy.c
index 84640a0c13f3590d456ab16de203d3a02dfc13b5..7ee980575208341b902d1e82285a26eb70e49d6b 100644 (file)
--- a/drivers/net/wan/x25_asy.c
+++ b/drivers/net/wan/x25_asy.c
@@ -307,6 +307,14 @@ static netdev_tx_t x25_asy_xmit(struct sk_buff *skb,
                return NETDEV_TX_OK;
        }
 
+       /* There should be a pseudo header of 1 byte added by upper layers.
+        * Check to make sure it is there before reading it.
+        */
+       if (skb->len < 1) {
+               kfree_skb(skb);
+               return NETDEV_TX_OK;
+       }
+
        switch (skb->data[0]) {
        case X25_IFACE_DATA:
                break;
@@ -322,7 +330,7 @@ static netdev_tx_t x25_asy_xmit(struct sk_buff *skb,
                if (err != LAPB_OK)
                        netdev_err(dev, "lapb_disconnect_request error: %d\n",
                                   err);
-               /* fall through */
+               fallthrough;
        default:
                kfree_skb(skb);
                return NETDEV_TX_OK;
@@ -752,6 +760,12 @@ static void x25_asy_setup(struct net_device *dev)
        dev->type               = ARPHRD_X25;
        dev->tx_queue_len       = 10;
 
+       /* When transmitting data:
+        * first this driver removes a pseudo header of 1 byte,
+        * then the lapb module prepends an LAPB header of at most 3 bytes.
+        */
+       dev->needed_headroom    = 3 - 1;
+
        /* New-style flags. */
        dev->flags              = IFF_NOARP;
 }