From: Nikolay Aleksandrov <nikolay@nvidia•com>
To: Pablo Neira Ayuso <pablo@netfilter•org>,
<netfilter-devel@vger•kernel.org>
Cc: <davem@davemloft•net>, <netdev@vger•kernel.org>,
<kuba@kernel•org>, <jeremy@azazel•net>
Subject: Re: [PATCH net-next,v3 5/9] bridge: resolve forwarding path for bridge devices
Date: Fri, 13 Nov 2020 17:40:50 +0200 [thread overview]
Message-ID: <d20f122a-8dfd-2da9-ddf3-7516184de26d@nvidia.com> (raw)
In-Reply-To: <4670e6a2-1a80-0edc-d464-52baf95cf78c@nvidia.com>
On 12/11/2020 02:53, Nikolay Aleksandrov wrote:
> On 11/11/2020 21:37, Pablo Neira Ayuso wrote:
>> Add .ndo_fill_forward_path for bridge devices.
>>
>> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter•org>
>> ---
>> include/linux/netdevice.h | 1 +
>> net/bridge/br_device.c | 24 ++++++++++++++++++++++++
>> 2 files changed, 25 insertions(+)
>>
>> diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h
>> index ca8525a1a797..d26de9a3d382 100644
>> --- a/include/linux/netdevice.h
>> +++ b/include/linux/netdevice.h
>> @@ -836,6 +836,7 @@ typedef u16 (*select_queue_fallback_t)(struct net_device *dev,
>> enum net_device_path_type {
>> DEV_PATH_ETHERNET = 0,
>> DEV_PATH_VLAN,
>> + DEV_PATH_BRIDGE,
>> };
>>
>> struct net_device_path {
>> diff --git a/net/bridge/br_device.c b/net/bridge/br_device.c
>> index 387403931a63..4c3a5334abe0 100644
>> --- a/net/bridge/br_device.c
>> +++ b/net/bridge/br_device.c
>> @@ -391,6 +391,29 @@ static int br_del_slave(struct net_device *dev, struct net_device *slave_dev)
>> return br_del_if(br, slave_dev);
>> }
>>
>> +static int br_fill_forward_path(struct net_device_path_ctx *ctx,
>> + struct net_device_path *path)
>> +{
>> + struct net_bridge_fdb_entry *f;
>> + struct net_bridge_port *dst;
>> + struct net_bridge *br;
>> +
>> + if (netif_is_bridge_port(ctx->dev))
>> + return -1;
>> +
>> + br = netdev_priv(ctx->dev);
>> + f = br_fdb_find_rcu(br, ctx->daddr, 0);
>> + if (!f || !f->dst)
>> + return -1;
>> +
>> + dst = READ_ONCE(f->dst);
>
> While this is ok, I meant that you have to test the ptr after. In theory between
> the !f->dst test above and now it could've become null, so to make it future-proof
> please test the null dst after deref, after the READ_ONCE(). I realize currently
> there are still problems after the change but we'll fix them.
>
On a second read this sounds too vague. :) I meant that there are still similar issues in
the bridge code today which I'll take care of. For this patch what I suggested should be enough.
Thanks,
Nik
>> + path->type = DEV_PATH_BRIDGE;
>> + path->dev = dst->br->dev;
>> + ctx->dev = dst->dev;
>> +
>> + return 0;
>> +}
>> +
>> static const struct ethtool_ops br_ethtool_ops = {
>> .get_drvinfo = br_getinfo,
>> .get_link = ethtool_op_get_link,
>> @@ -425,6 +448,7 @@ static const struct net_device_ops br_netdev_ops = {
>> .ndo_bridge_setlink = br_setlink,
>> .ndo_bridge_dellink = br_dellink,
>> .ndo_features_check = passthru_features_check,
>> + .ndo_fill_forward_path = br_fill_forward_path,
>> };
>>
>> static struct device_type br_type = {
>>
>
next prev parent reply other threads:[~2020-11-13 15:41 UTC|newest]
Thread overview: 29+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-11-11 19:37 [PATCH net-next,v3 0/9] netfilter: flowtable bridge and vlan enhancements Pablo Neira Ayuso
2020-11-11 19:37 ` [PATCH net-next,v3 1/9] netfilter: flowtable: add hash offset field to tuple Pablo Neira Ayuso
2020-11-11 19:37 ` [PATCH net-next,v3 2/9] netfilter: flowtable: add xmit path types Pablo Neira Ayuso
2020-11-11 19:37 ` [PATCH net-next,v3 3/9] net: resolve forwarding path from virtual netdevice and HW destination address Pablo Neira Ayuso
2020-11-14 1:42 ` Jakub Kicinski
2020-11-14 12:00 ` Pablo Neira Ayuso
2020-11-11 19:37 ` [PATCH net-next,v3 4/9] net: 8021q: resolve forwarding path for vlan devices Pablo Neira Ayuso
2020-11-11 19:37 ` [PATCH net-next,v3 5/9] bridge: resolve forwarding path for bridge devices Pablo Neira Ayuso
2020-11-12 0:53 ` Nikolay Aleksandrov
2020-11-13 15:40 ` Nikolay Aleksandrov [this message]
2020-11-11 19:37 ` [PATCH net-next,v3 6/9] netfilter: flowtable: use dev_fill_forward_path() to obtain ingress device Pablo Neira Ayuso
2020-11-11 19:37 ` [PATCH net-next,v3 7/9] netfilter: flowtable: use dev_fill_forward_path() to obtain egress device Pablo Neira Ayuso
2020-11-11 19:37 ` [PATCH net-next,v3 8/9] netfilter: flowtable: add vlan support Pablo Neira Ayuso
2020-11-11 19:37 ` [PATCH net-next,v3 9/9] selftests: netfilter: flowtable bridge and VLAN support Pablo Neira Ayuso
2020-11-14 1:55 ` [PATCH net-next,v3 0/9] netfilter: flowtable bridge and vlan enhancements Jakub Kicinski
2020-11-14 11:59 ` Pablo Neira Ayuso
2020-11-14 14:00 ` Tobias Waldekranz
2020-11-14 17:03 ` Jakub Kicinski
2020-11-16 22:18 ` Pablo Neira Ayuso
2020-11-16 22:28 ` Jakub Kicinski
2020-11-16 22:36 ` Pablo Neira Ayuso
2020-11-16 22:45 ` Jakub Kicinski
2020-11-16 22:56 ` Pablo Neira Ayuso
2020-11-21 12:31 ` Pablo Neira Ayuso
2020-11-21 18:15 ` Jakub Kicinski
2020-11-21 18:56 ` Pablo Neira Ayuso
2020-11-21 19:23 ` Jakub Kicinski
2020-11-22 11:33 ` Pablo Neira Ayuso
2020-11-16 22:31 ` Pablo Neira Ayuso
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