6lowpan: consider checksum bytes in fragmentation threshold
Change the threshold for framentation of a lowpan packet from
using the MTU size to now use the MTU size minus the checksum length,
which is added by the hardware. For IEEE 802.15.4, this effectively
changes it from 127 bytes to 125 bytes.
Signed-off-by: Alan Ott <alan@signal11.us>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/ieee802154/6lowpan.c b/net/ieee802154/6lowpan.c
index 6d42c17..f651da6 100644
--- a/net/ieee802154/6lowpan.c
+++ b/net/ieee802154/6lowpan.c
@@ -1047,7 +1047,8 @@
goto error;
}
- if (skb->len <= IEEE802154_MTU) {
+ /* Send directly if less than the MTU minus the 2 checksum bytes. */
+ if (skb->len <= IEEE802154_MTU - IEEE802154_MFR_SIZE) {
err = dev_queue_xmit(skb);
goto out;
}