net: systemport: fix double shift of a vlan_tci by VLAN_PRIO_SHIFT
authorColin Ian King <colin.king@canonical.com>
Wed, 8 Jul 2020 18:37:23 +0000 (19:37 +0100)
committerDavid S. Miller <davem@davemloft.net>
Thu, 9 Jul 2020 20:06:56 +0000 (13:06 -0700)
Currently the u16 skb->vlan_tci is being right  shifted twice by
VLAN_PRIO_SHIFT, once in the macro skb_vlan_tag_get_pri and explicitly
by VLAN_PRIO_SHIFT afterwards. The combined shift amount is larger than
the u16 so the end result is always zero.  Remove the second explicit
shift as this is extraneous.

Fixes: 6e9fdb60d362 ("net: systemport: Add support for VLAN transmit acceleration")
Addresses-Coverity: ("Operands don't affect result")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Acked-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
drivers/net/ethernet/broadcom/bcmsysport.c

index b470551..dfed9ad 100644 (file)
@@ -1250,8 +1250,7 @@ static struct sk_buff *bcm_sysport_insert_tsb(struct sk_buff *skb,
        memset(tsb, 0, sizeof(*tsb));
 
        if (skb_vlan_tag_present(skb)) {
-               tsb->pcp_dei_vid = (skb_vlan_tag_get_prio(skb) >>
-                                   VLAN_PRIO_SHIFT & PCP_DEI_MASK);
+               tsb->pcp_dei_vid = skb_vlan_tag_get_prio(skb) & PCP_DEI_MASK;
                tsb->pcp_dei_vid |= (u32)skb_vlan_tag_get_id(skb) << VID_SHIFT;
        }