1 files changed, 39 insertions, 13 deletions

diff --git a/drivers/net/ethernet/intel/ice/ice_ethtool.c b/drivers/net/ethernet/intel/ice/ice_ethtool.c
index 1db304c01d10..c71a9b528d6d 100644
--- a/drivers/net/ethernet/intel/ice/ice_ethtool.c
+++ b/drivers/net/ethernet/intel/ice/ice_ethtool.c
@@ -26,7 +26,7 @@ static int ice_q_stats_len(struct net_device *netdev)
 {
         struct ice_netdev_priv *np = netdev_priv(netdev);
 
-        return ((np->vsi->num_txq + np->vsi->num_rxq) *
+        return ((np->vsi->alloc_txq + np->vsi->alloc_rxq) *
                 (sizeof(struct ice_q_stats) / sizeof(u64)));
 }
 
@@ -218,7 +218,7 @@ static void ice_get_strings(struct net_device *netdev, u32 stringset, u8 *data)
                         p += ETH_GSTRING_LEN;
                 }
 
-                ice_for_each_txq(vsi, i) {
+                ice_for_each_alloc_txq(vsi, i) {
                         snprintf(p, ETH_GSTRING_LEN,
                                  "tx-queue-%u.tx_packets", i);
                         p += ETH_GSTRING_LEN;
@@ -226,7 +226,7 @@ static void ice_get_strings(struct net_device *netdev, u32 stringset, u8 *data)
                         p += ETH_GSTRING_LEN;
                 }
 
-                ice_for_each_rxq(vsi, i) {
+                ice_for_each_alloc_rxq(vsi, i) {
                         snprintf(p, ETH_GSTRING_LEN,
                                  "rx-queue-%u.rx_packets", i);
                         p += ETH_GSTRING_LEN;
@@ -253,6 +253,24 @@ static int ice_get_sset_count(struct net_device *netdev, int sset)
 {
         switch (sset) {
         case ETH_SS_STATS:
+                /* The number (and order) of strings reported *must* remain
+                 * constant for a given netdevice. This function must not
+                 * report a different number based on run time parameters
+                 * (such as the number of queues in use, or the setting of
+                 * a private ethtool flag). This is due to the nature of the
+                 * ethtool stats API.
+                 *
+                 * User space programs such as ethtool must make 3 separate
+                 * ioctl requests, one for size, one for the strings, and
+                 * finally one for the stats. Since these cross into
+                 * user space, changes to the number or size could result in
+                 * undefined memory access or incorrect string<->value
+                 * correlations for statistics.
+                 *
+                 * Even if it appears to be safe, changes to the size or
+                 * order of strings will suffer from race conditions and are
+                 * not safe.
+                 */
                 return ICE_ALL_STATS_LEN(netdev);
         default:
                 return -EOPNOTSUPP;
@@ -280,18 +298,26 @@ ice_get_ethtool_stats(struct net_device *netdev,
         /* populate per queue stats */
         rcu_read_lock();
 
-        ice_for_each_txq(vsi, j) {
+        ice_for_each_alloc_txq(vsi, j) {
                 ring = READ_ONCE(vsi->tx_rings[j]);
-                if (!ring)
-                        continue;
-                data[i++] = ring->stats.pkts;
-                data[i++] = ring->stats.bytes;
+                if (ring) {
+                        data[i++] = ring->stats.pkts;
+                        data[i++] = ring->stats.bytes;
+                } else {
+                        data[i++] = 0;
+                        data[i++] = 0;
+                }
         }
 
-        ice_for_each_rxq(vsi, j) {
+        ice_for_each_alloc_rxq(vsi, j) {
                 ring = READ_ONCE(vsi->rx_rings[j]);
-                data[i++] = ring->stats.pkts;
-                data[i++] = ring->stats.bytes;
+                if (ring) {
+                        data[i++] = ring->stats.pkts;
+                        data[i++] = ring->stats.bytes;
+                } else {
+                        data[i++] = 0;
+                        data[i++] = 0;
+                }
         }
 
         rcu_read_unlock();
@@ -519,7 +545,7 @@ ice_set_ringparam(struct net_device *netdev, struct ethtool_ringparam *ring)
                 goto done;
         }
 
-        for (i = 0; i < vsi->num_txq; i++) {
+        for (i = 0; i < vsi->alloc_txq; i++) {
                 /* clone ring and setup updated count */
                 tx_rings[i] = *vsi->tx_rings[i];
                 tx_rings[i].count = new_tx_cnt;
@@ -551,7 +577,7 @@ process_rx:
                 goto done;
         }
 
-        for (i = 0; i < vsi->num_rxq; i++) {
+        for (i = 0; i < vsi->alloc_rxq; i++) {
                 /* clone ring and setup updated count */
                 rx_rings[i] = *vsi->rx_rings[i];
                 rx_rings[i].count = new_rx_cnt;