ethtool: Fail number of channels change when it conflicts with rxnfc

Similar to what we do with the hash indirection table [1], when network
flow classification rules are forwarding traffic to channels greater
than the requested number of channels, fail the operation.
Without this, traffic could be directed to channels which no longer
exist (dropped) after changing number of channels.

[1] commit d4ab4286276f ("ethtool: correctly ensure {GS}CHANNELS doesn't conflict with GS{RXFH}")

Reviewed-by: Tariq Toukan <tariqt@nvidia.com>
Signed-off-by: Gal Pressman <gal@nvidia.com>
Link: https://lore.kernel.org/r/20221106123127.522985-1-gal@nvidia.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>

diff --git a/net/ethtool/channels.c b/net/ethtool/channels.c
index 403158862011588ded7a448b13e39702551b2df4..c7e37130647e4489f6a1b6ee0e7359e6b73b0099 100644 (file)
--- a/net/ethtool/channels.c
+++ b/net/ethtool/channels.c
@@ -116,9 +116,10 @@ int ethnl_set_channels(struct sk_buff *skb, struct genl_info *info)
        struct ethtool_channels channels = {};
        struct ethnl_req_info req_info = {};
        struct nlattr **tb = info->attrs;
-       u32 err_attr, max_rx_in_use = 0;
+       u32 err_attr, max_rxfh_in_use;
        const struct ethtool_ops *ops;
        struct net_device *dev;
+       u64 max_rxnfc_in_use;
        int ret;
 
        ret = ethnl_parse_header_dev_get(&req_info,
@@ -189,15 +190,23 @@ int ethnl_set_channels(struct sk_buff *skb, struct genl_info *info)
        }
 
        /* ensure the new Rx count fits within the configured Rx flow
-        * indirection table settings
+        * indirection table/rxnfc settings
         */
-       if (netif_is_rxfh_configured(dev) &&
-           !ethtool_get_max_rxfh_channel(dev, &max_rx_in_use) &&
-           (channels.combined_count + channels.rx_count) <= max_rx_in_use) {
+       if (ethtool_get_max_rxnfc_channel(dev, &max_rxnfc_in_use))
+               max_rxnfc_in_use = 0;
+       if (!netif_is_rxfh_configured(dev) ||
+           ethtool_get_max_rxfh_channel(dev, &max_rxfh_in_use))
+               max_rxfh_in_use = 0;
+       if (channels.combined_count + channels.rx_count <= max_rxfh_in_use) {
                ret = -EINVAL;
                GENL_SET_ERR_MSG(info, "requested channel counts are too low for existing indirection table settings");
                goto out_ops;
        }
+       if (channels.combined_count + channels.rx_count <= max_rxnfc_in_use) {
+               ret = -EINVAL;
+               GENL_SET_ERR_MSG(info, "requested channel counts are too low for existing ntuple filter settings");
+               goto out_ops;
+       }
 
        /* Disabling channels, query zero-copy AF_XDP sockets */
        from_channel = channels.combined_count +

diff --git a/net/ethtool/common.c b/net/ethtool/common.c
index ee3e02da0013c606c79500e9b6640accc3c4ff43..21cfe85572057fbee9a7e55af2d2d04707529ea5 100644 (file)
--- a/net/ethtool/common.c
+++ b/net/ethtool/common.c
@@ -512,6 +512,72 @@ int __ethtool_get_link(struct net_device *dev)
        return netif_running(dev) && dev->ethtool_ops->get_link(dev);
 }
 
+static int ethtool_get_rxnfc_rule_count(struct net_device *dev)
+{
+       const struct ethtool_ops *ops = dev->ethtool_ops;
+       struct ethtool_rxnfc info = {
+               .cmd = ETHTOOL_GRXCLSRLCNT,
+       };
+       int err;
+
+       err = ops->get_rxnfc(dev, &info, NULL);
+       if (err)
+               return err;
+
+       return info.rule_cnt;
+}
+
+int ethtool_get_max_rxnfc_channel(struct net_device *dev, u64 *max)
+{
+       const struct ethtool_ops *ops = dev->ethtool_ops;
+       struct ethtool_rxnfc *info;
+       int err, i, rule_cnt;
+       u64 max_ring = 0;
+
+       if (!ops->get_rxnfc)
+               return -EOPNOTSUPP;
+
+       rule_cnt = ethtool_get_rxnfc_rule_count(dev);
+       if (rule_cnt <= 0)
+               return -EINVAL;
+
+       info = kvzalloc(struct_size(info, rule_locs, rule_cnt), GFP_KERNEL);
+       if (!info)
+               return -ENOMEM;
+
+       info->cmd = ETHTOOL_GRXCLSRLALL;
+       info->rule_cnt = rule_cnt;
+       err = ops->get_rxnfc(dev, info, info->rule_locs);
+       if (err)
+               goto err_free_info;
+
+       for (i = 0; i < rule_cnt; i++) {
+               struct ethtool_rxnfc rule_info = {
+                       .cmd = ETHTOOL_GRXCLSRULE,
+                       .fs.location = info->rule_locs[i],
+               };
+
+               err = ops->get_rxnfc(dev, &rule_info, NULL);
+               if (err)
+                       goto err_free_info;
+
+               if (rule_info.fs.ring_cookie != RX_CLS_FLOW_DISC &&
+                   rule_info.fs.ring_cookie != RX_CLS_FLOW_WAKE &&
+                   !(rule_info.flow_type & FLOW_RSS) &&
+                   !ethtool_get_flow_spec_ring_vf(rule_info.fs.ring_cookie))
+                       max_ring =
+                               max_t(u64, max_ring, rule_info.fs.ring_cookie);
+       }
+
+       kvfree(info);
+       *max = max_ring;
+       return 0;
+
+err_free_info:
+       kvfree(info);
+       return err;
+}
+
 int ethtool_get_max_rxfh_channel(struct net_device *dev, u32 *max)
 {
        u32 dev_size, current_max = 0;

diff --git a/net/ethtool/common.h b/net/ethtool/common.h
index c1779657e074f25998901deee41a41613172b024..b1b9db810ecac3c1225b072847415671f01760b2 100644 (file)
--- a/net/ethtool/common.h
+++ b/net/ethtool/common.h
@@ -43,6 +43,7 @@ bool convert_legacy_settings_to_link_ksettings(
        struct ethtool_link_ksettings *link_ksettings,
        const struct ethtool_cmd *legacy_settings);
 int ethtool_get_max_rxfh_channel(struct net_device *dev, u32 *max);
+int ethtool_get_max_rxnfc_channel(struct net_device *dev, u64 *max);
 int __ethtool_get_ts_info(struct net_device *dev, struct ethtool_ts_info *info);
 
 extern const struct ethtool_phy_ops *ethtool_phy_ops;

diff --git a/net/ethtool/ioctl.c b/net/ethtool/ioctl.c
index b6835136c53fff320f34308f65d796a7d7cf7f06..e40f5e9e109b1d3d66f7011e9250a7bd3ec71691 100644 (file)
--- a/net/ethtool/ioctl.c
+++ b/net/ethtool/ioctl.c
@@ -1789,7 +1789,8 @@ static noinline_for_stack int ethtool_set_channels(struct net_device *dev,
 {
        struct ethtool_channels channels, curr = { .cmd = ETHTOOL_GCHANNELS };
        u16 from_channel, to_channel;
-       u32 max_rx_in_use = 0;
+       u64 max_rxnfc_in_use;
+       u32 max_rxfh_in_use;
        unsigned int i;
        int ret;
 
@@ -1820,11 +1821,15 @@ static noinline_for_stack int ethtool_set_channels(struct net_device *dev,
                return -EINVAL;
 
        /* ensure the new Rx count fits within the configured Rx flow
-        * indirection table settings */
-       if (netif_is_rxfh_configured(dev) &&
-           !ethtool_get_max_rxfh_channel(dev, &max_rx_in_use) &&
-           (channels.combined_count + channels.rx_count) <= max_rx_in_use)
-           return -EINVAL;
+        * indirection table/rxnfc settings */
+       if (ethtool_get_max_rxnfc_channel(dev, &max_rxnfc_in_use))
+               max_rxnfc_in_use = 0;
+       if (!netif_is_rxfh_configured(dev) ||
+           ethtool_get_max_rxfh_channel(dev, &max_rxfh_in_use))
+               max_rxfh_in_use = 0;
+       if (channels.combined_count + channels.rx_count <=
+           max_t(u64, max_rxnfc_in_use, max_rxfh_in_use))
+               return -EINVAL;
 
        /* Disabling channels, query zero-copy AF_XDP sockets */
        from_channel = channels.combined_count +