From mboxrd@z Thu Jan 1 00:00:00 1970 From: Florian Fainelli Subject: Re: [PATCH v2 net] net: dsa: Discard frames from unused ports Date: Sat, 7 Apr 2018 12:57:27 -0700 Message-ID: References: <1523126260-15559-1-git-send-email-andrew@lunn.ch> Mime-Version: 1.0 Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: 7bit Cc: netdev , Vivien Didelot To: Andrew Lunn , David Miller Return-path: Received: from mail-ot0-f195.google.com ([74.125.82.195]:39516 "EHLO mail-ot0-f195.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752461AbeDGT5a (ORCPT ); Sat, 7 Apr 2018 15:57:30 -0400 Received: by mail-ot0-f195.google.com with SMTP id a14-v6so4673136otf.6 for ; Sat, 07 Apr 2018 12:57:30 -0700 (PDT) In-Reply-To: <1523126260-15559-1-git-send-email-andrew@lunn.ch> Content-Language: en-US Sender: netdev-owner@vger.kernel.org List-ID: On 04/07/2018 11:37 AM, Andrew Lunn wrote: > The Marvell switches under some conditions will pass a frame to the > host with the port being the CPU port. Such frames are invalid, and > should be dropped. Not dropping them can result in a crash when > incrementing the receive statistics for an invalid port. > > Reported-by: Chris Healy > Fixes: 91da11f870f0 ("net: Distributed Switch Architecture protocol support") > Signed-off-by: Andrew Lunn Reviewed-by: Florian Fainelli It looks like the stable scripts now test build against several kernel versions so we should be able to know which stable versions need a specific fix that does not involve dsa_master_find_slave(). Thanks Andrew! > --- > v2: > Use an earlier revision for the fixes tag. > Add unlikely annotation > --- > net/dsa/dsa_priv.h | 8 +++++++- > 1 file changed, 7 insertions(+), 1 deletion(-) > > diff --git a/net/dsa/dsa_priv.h b/net/dsa/dsa_priv.h > index 70de7895e5b8..053731473c99 100644 > --- a/net/dsa/dsa_priv.h > +++ b/net/dsa/dsa_priv.h > @@ -126,6 +126,7 @@ static inline struct net_device *dsa_master_find_slave(struct net_device *dev, > struct dsa_port *cpu_dp = dev->dsa_ptr; > struct dsa_switch_tree *dst = cpu_dp->dst; > struct dsa_switch *ds; > + struct dsa_port *slave_port; > > if (device < 0 || device >= DSA_MAX_SWITCHES) > return NULL; > @@ -137,7 +138,12 @@ static inline struct net_device *dsa_master_find_slave(struct net_device *dev, > if (port < 0 || port >= ds->num_ports) > return NULL; > > - return ds->ports[port].slave; > + slave_port = &ds->ports[port]; > + > + if (unlikely(slave_port->type != DSA_PORT_TYPE_USER)) > + return NULL; > + > + return slave_port->slave; > } > > /* port.c */ > -- Florian