if_link: Add an additional parameter to ifla_vf_info for RSS querying

Add configuration setting for drivers to allow/block an RSS Redirection
Table and a Hash Key querying for discrete VFs.

On some devices VF share the mentioned above information with PF and
querying it may adduce a theoretical security risk. We want to let a
system administrator to decide if he/she wants to take this risk or not.

Signed-off-by: Vlad Zolotarov <vladz@cloudius-systems.com>
Tested-by: Phil Schmitt <phillip.j.schmitt@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>

4 files changed, 43 insertions, 6 deletions

diff --git a/include/linux/if_link.h b/include/linux/if_link.h
index 119130e9298b..da4929927f69 100644
--- a/include/linux/if_link.h
+++ b/include/linux/if_link.h
@@ -14,5 +14,6 @@ struct ifla_vf_info {
         __u32 linkstate;
         __u32 min_tx_rate;
         __u32 max_tx_rate;
+        __u32 rss_query_en;
 };
 #endif /* _LINUX_IF_LINK_H */
diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h
index bf6d9df34d7b..13acb3d8ecdd 100644
--- a/include/linux/netdevice.h
+++ b/include/linux/netdevice.h
@@ -878,6 +878,11 @@ typedef u16 (*select_queue_fallback_t)(struct net_device *dev,
  * int (*ndo_set_vf_link_state)(struct net_device *dev, int vf, int link_state);
  * int (*ndo_set_vf_port)(struct net_device *dev, int vf,
  *                        struct nlattr *port[]);
+ *
+ *      Enable or disable the VF ability to query its RSS Redirection Table and
+ *      Hash Key. This is needed since on some devices VF share this information
+ *      with PF and querying it may adduce a theoretical security risk.
+ * int (*ndo_set_vf_rss_query_en)(struct net_device *dev, int vf, bool setting);
  * int (*ndo_get_vf_port)(struct net_device *dev, int vf, struct sk_buff *skb);
  * int (*ndo_setup_tc)(struct net_device *dev, u8 tc)
  *      Called to setup 'tc' number of traffic classes in the net device. This
@@ -1099,6 +1104,9 @@ struct net_device_ops {
                                                    struct nlattr *port[]);
         int                     (*ndo_get_vf_port)(struct net_device *dev,
                                                    int vf, struct sk_buff *skb);
+        int                     (*ndo_set_vf_rss_query_en)(
+                                                   struct net_device *dev,
+                                                   int vf, bool setting);
         int                     (*ndo_setup_tc)(struct net_device *dev, u8 tc);
 #if IS_ENABLED(CONFIG_FCOE)
         int                     (*ndo_fcoe_enable)(struct net_device *dev);
diff --git a/include/uapi/linux/if_link.h b/include/uapi/linux/if_link.h
index 7ffb18df01ca..d9cd19214b98 100644
--- a/include/uapi/linux/if_link.h
+++ b/include/uapi/linux/if_link.h
@@ -465,6 +465,9 @@ enum {
         IFLA_VF_SPOOFCHK,       /* Spoof Checking on/off switch */
         IFLA_VF_LINK_STATE,     /* link state enable/disable/auto switch */
         IFLA_VF_RATE,           /* Min and Max TX Bandwidth Allocation */
+        IFLA_VF_RSS_QUERY_EN,   /* RSS Redirection Table and Hash Key query
+                                 * on/off switch
+                                 */
         __IFLA_VF_MAX,
 };
 
@@ -509,6 +512,11 @@ struct ifla_vf_link_state {
         __u32 link_state;
 };
 
+struct ifla_vf_rss_query_en {
+        __u32 vf;
+        __u32 setting;
+};
+
 /* VF ports management section
  *
  *      Nested layout of set/get msg is:
diff --git a/net/core/rtnetlink.c b/net/core/rtnetlink.c
index 7a836152359b..358d52a38533 100644
--- a/net/core/rtnetlink.c
+++ b/net/core/rtnetlink.c
@@ -818,7 +818,8 @@ static inline int rtnl_vfinfo_size(const struct net_device *dev,
                          nla_total_size(sizeof(struct ifla_vf_vlan)) +
                          nla_total_size(sizeof(struct ifla_vf_spoofchk)) +
                          nla_total_size(sizeof(struct ifla_vf_rate)) +
-                         nla_total_size(sizeof(struct ifla_vf_link_state)));
+                         nla_total_size(sizeof(struct ifla_vf_link_state)) +
+                         nla_total_size(sizeof(struct ifla_vf_rss_query_en)));
                 return size;
         } else
                 return 0;
@@ -1132,14 +1133,16 @@ static int rtnl_fill_ifinfo(struct sk_buff *skb, struct net_device *dev,
                         struct ifla_vf_tx_rate vf_tx_rate;
                         struct ifla_vf_spoofchk vf_spoofchk;
                         struct ifla_vf_link_state vf_linkstate;
+                        struct ifla_vf_rss_query_en vf_rss_query_en;
 
                         /*
                          * Not all SR-IOV capable drivers support the
-                         * spoofcheck query.  Preset to -1 so the user
-                         * space tool can detect that the driver didn't
-                         * report anything.
+                         * spoofcheck and "RSS query enable" query.  Preset to
+                         * -1 so the user space tool can detect that the driver
+                         * didn't report anything.
                          */
                         ivi.spoofchk = -1;
+                        ivi.rss_query_en = -1;
                         memset(ivi.mac, 0, sizeof(ivi.mac));
                         /* The default value for VF link state is "auto"
                          * IFLA_VF_LINK_STATE_AUTO which equals zero
@@ -1152,7 +1155,8 @@ static int rtnl_fill_ifinfo(struct sk_buff *skb, struct net_device *dev,
                                 vf_rate.vf =
                                 vf_tx_rate.vf =
                                 vf_spoofchk.vf =
-                                vf_linkstate.vf = ivi.vf;
+                                vf_linkstate.vf =
+                                vf_rss_query_en.vf = ivi.vf;
 
                         memcpy(vf_mac.mac, ivi.mac, sizeof(ivi.mac));
                         vf_vlan.vlan = ivi.vlan;
@@ -1162,6 +1166,7 @@ static int rtnl_fill_ifinfo(struct sk_buff *skb, struct net_device *dev,
                         vf_rate.max_tx_rate = ivi.max_tx_rate;
                         vf_spoofchk.setting = ivi.spoofchk;
                         vf_linkstate.link_state = ivi.linkstate;
+                        vf_rss_query_en.setting = ivi.rss_query_en;
                         vf = nla_nest_start(skb, IFLA_VF_INFO);
                         if (!vf) {
                                 nla_nest_cancel(skb, vfinfo);
@@ -1176,7 +1181,10 @@ static int rtnl_fill_ifinfo(struct sk_buff *skb, struct net_device *dev,
                             nla_put(skb, IFLA_VF_SPOOFCHK, sizeof(vf_spoofchk),
                                     &vf_spoofchk) ||
                             nla_put(skb, IFLA_VF_LINK_STATE, sizeof(vf_linkstate),
-                                    &vf_linkstate))
+                                    &vf_linkstate) ||
+                            nla_put(skb, IFLA_VF_RSS_QUERY_EN,
+                                    sizeof(vf_rss_query_en),
+                                    &vf_rss_query_en))
                                 goto nla_put_failure;
                         nla_nest_end(skb, vf);
                 }
@@ -1290,6 +1298,7 @@ static const struct nla_policy ifla_vf_policy[IFLA_VF_MAX+1] = {
         [IFLA_VF_SPOOFCHK]      = { .len = sizeof(struct ifla_vf_spoofchk) },
         [IFLA_VF_RATE]          = { .len = sizeof(struct ifla_vf_rate) },
         [IFLA_VF_LINK_STATE]    = { .len = sizeof(struct ifla_vf_link_state) },
+        [IFLA_VF_RSS_QUERY_EN]  = { .len = sizeof(struct ifla_vf_rss_query_en) },
 };
 
 static const struct nla_policy ifla_port_policy[IFLA_PORT_MAX+1] = {
@@ -1500,6 +1509,17 @@ static int do_setvfinfo(struct net_device *dev, struct nlattr *attr)
                                                                  ivl->link_state);
                         break;
                 }
+                case IFLA_VF_RSS_QUERY_EN: {
+                        struct ifla_vf_rss_query_en *ivrssq_en;
+
+                        ivrssq_en = nla_data(vf);
+                        err = -EOPNOTSUPP;
+                        if (ops->ndo_set_vf_rss_query_en)
+                                err = ops->ndo_set_vf_rss_query_en(dev,
+                                                            ivrssq_en->vf,
+                                                            ivrssq_en->setting);
+                        break;
+                }
                 default:
                         err = -EINVAL;
                         break;