net: systemport: Fix reception of BPDUs

[ Upstream commit a40061ea2e39494104602b3048751341bda374a1 ]

SYSTEMPORT has its RXCHK parser block that attempts to validate the
packet structures, unfortunately setting the L2 header check bit will
cause Bridge PDUs (BPDUs) to be incorrectly rejected because they look
like LLC/SNAP packets with a non-IPv4 or non-IPv6 Ethernet Type.

Fixes: 4e8aedfe78c7 ("net: systemport: Turn on offloads by default")
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>

diff --git a/drivers/net/ethernet/broadcom/bcmsysport.c b/drivers/net/ethernet/broadcom/bcmsysport.c
index fc16b2b0d0e94def8546ecf6c020e1c7c9561618..0bdbc72605e1fd1ad3d048651894d546665b4c8c 100644 (file)
--- a/drivers/net/ethernet/broadcom/bcmsysport.c
+++ b/drivers/net/ethernet/broadcom/bcmsysport.c
@@ -134,6 +134,10 @@ static int bcm_sysport_set_rx_csum(struct net_device *dev,
 
        priv->rx_chk_en = !!(wanted & NETIF_F_RXCSUM);
        reg = rxchk_readl(priv, RXCHK_CONTROL);
+       /* Clear L2 header checks, which would prevent BPDUs
+        * from being received.
+        */
+       reg &= ~RXCHK_L2_HDR_DIS;
        if (priv->rx_chk_en)
                reg |= RXCHK_EN;
        else