Merge tag 'powerpc-5.9-3' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc...

[linux-2.6-microblaze.git] / drivers / net / wan / hdlc_x25.c

diff --git a/drivers/net/wan/hdlc_x25.c b/drivers/net/wan/hdlc_x25.c
index f70336b..f52b9fe 100644 (file)
--- a/drivers/net/wan/hdlc_x25.c
+++ b/drivers/net/wan/hdlc_x25.c
@@ -107,8 +107,14 @@ static netdev_tx_t x25_xmit(struct sk_buff *skb, struct net_device *dev)
 {
        int result;
 
+       /* 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;
+       }
 
-       /* X.25 to LAPB */
        switch (skb->data[0]) {
        case X25_IFACE_DATA:    /* Data to be transmitted */
                skb_pull(skb, 1);
@@ -294,6 +300,15 @@ static int x25_ioctl(struct net_device *dev, struct ifreq *ifr)
                        return result;
 
                memcpy(&state(hdlc)->settings, &new_settings, size);
+
+               /* There's no header_ops so hard_header_len should be 0. */
+               dev->hard_header_len = 0;
+               /* When transmitting data:
+                * first we'll remove a pseudo header of 1 byte,
+                * then we'll prepend an LAPB header of at most 3 bytes.
+                */
+               dev->needed_headroom = 3 - 1;
+
                dev->type = ARPHRD_X25;
                call_netdevice_notifiers(NETDEV_POST_TYPE_CHANGE, dev);
                netif_dormant_off(dev);