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 53a506b0d79036ecb3c8b6e5a268a9e2ee208801..95874c10c23b63110f5caf07eb3682841c50cbda 100644 (file)
--- a/drivers/net/ethernet/broadcom/bcmsysport.c
+++ b/drivers/net/ethernet/broadcom/bcmsysport.c
@@ -104,6 +104,10 @@ 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