Re: [PATCH 4.9 040/102] net: dsa: Fix duplicate frames flooded by learning

From: Florian Fainelli
Date: Mon Apr 06 2020 - 20:42:27 EST




On 4/1/2020 9:17 AM, Greg Kroah-Hartman wrote:
> From: Florian Fainelli <f.fainelli@xxxxxxxxx>
>
> [ Upstream commit 0e62f543bed03a64495bd2651d4fe1aa4bcb7fe5 ]
>
> When both the switch and the bridge are learning about new addresses,
> switch ports attached to the bridge would see duplicate ARP frames
> because both entities would attempt to send them.
>
> Fixes: 5037d532b83d ("net: dsa: add Broadcom tag RX/TX handler")
> Reported-by: Maxime Bizon <mbizon@xxxxxxxxxx>
> Signed-off-by: Florian Fainelli <f.fainelli@xxxxxxxxx>
> Reviewed-by: Vivien Didelot <vivien.didelot@xxxxxxxxx>
> Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
> ---
> net/dsa/tag_brcm.c | 2 ++
> 1 file changed, 2 insertions(+)
>
> --- a/net/dsa/tag_brcm.c
> +++ b/net/dsa/tag_brcm.c
> @@ -84,6 +84,8 @@ static struct sk_buff *brcm_tag_xmit(str
> brcm_tag[2] = BRCM_IG_DSTMAP2_MASK;
> brcm_tag[3] = (1 << p->port) & BRCM_IG_DSTMAP1_MASK;
>
> + skb->offload_fwd_mark = 1;

This is incorrectly placed, the assignment should be in brcm_tag_rcv().
It looks like only linux-4.9.y is affected. Sorry for not noticing this
earlier. Do you want me to submit a correcting patch?
--
Florian