net/mlx5: fix flow validation

Item spec and last are wrongly compared to the NIC capability causing a
validation failure when the mask is null.
This validation function should only verify the user is not configuring
unsupported matching fields.

Fixes: 2097d0d1e2cc ("net/mlx5: support basic flow items and actions")
Cc: stable@dpdk.org
Signed-off-by: Nelio Laranjeiro <nelio.laranjeiro@6wind.com>

diff --git a/drivers/net/mlx5/mlx5_flow.c b/drivers/net/mlx5/mlx5_flow.c
index 129311d..38811bb 100644 (file)
--- a/drivers/net/mlx5/mlx5_flow.c
+++ b/drivers/net/mlx5/mlx5_flow.c
@@ -538,7 +538,7 @@ struct ibv_spec_header {
 };
 
 /**
- * Check support for a given item.
+ * Check item is fully supported by the NIC matching capability.
  *
  * @param item[in]
  *   Item specification.
@@ -555,60 +555,33 @@ static int
 mlx5_flow_item_validate(const struct rte_flow_item *item,
                        const uint8_t *mask, unsigned int size)
 {
-       if (!item->spec && (item->mask || item->last)) {
-               rte_errno = EINVAL;
-               return -rte_errno;
-       }
-       if (item->spec && !item->mask) {
-               unsigned int i;
-               const uint8_t *spec = item->spec;
-
-               for (i = 0; i < size; ++i)
-                       if ((spec[i] | mask[i]) != mask[i]) {
-                               rte_errno = EINVAL;
-                               return -rte_errno;
-                       }
-       }
-       if (item->last && !item->mask) {
-               unsigned int i;
-               const uint8_t *spec = item->last;
-
-               for (i = 0; i < size; ++i)
-                       if ((spec[i] | mask[i]) != mask[i]) {
-                               rte_errno = EINVAL;
-                               return -rte_errno;
-                       }
-       }
-       if (item->mask) {
-               unsigned int i;
-               const uint8_t *spec = item->spec;
-
-               for (i = 0; i < size; ++i)
-                       if ((spec[i] | mask[i]) != mask[i]) {
-                               rte_errno = EINVAL;
-                               return -rte_errno;
-                       }
-       }
-       if (item->spec && item->last) {
-               uint8_t spec[size];
-               uint8_t last[size];
-               const uint8_t *apply = mask;
-               unsigned int i;
-               int ret;
+       unsigned int i;
+       const uint8_t *spec = item->spec;
+       const uint8_t *last = item->last;
+       const uint8_t *m = item->mask ? item->mask : mask;
 
-               if (item->mask)
-                       apply = item->mask;
-               for (i = 0; i < size; ++i) {
-                       spec[i] = ((const uint8_t *)item->spec)[i] & apply[i];
-                       last[i] = ((const uint8_t *)item->last)[i] & apply[i];
-               }
-               ret = memcmp(spec, last, size);
-               if (ret != 0) {
-                       rte_errno = EINVAL;
-                       return -rte_errno;
-               }
+       if (!spec && (item->mask || last))
+               goto error;
+       if (!spec)
+               return 0;
+       /*
+        * Single-pass check to make sure that:
+        * - item->mask is supported, no bits are set outside mask.
+        * - Both masked item->spec and item->last are equal (no range
+        *   supported).
+        */
+       for (i = 0; i < size; i++) {
+               if (!m[i])
+                       continue;
+               if ((m[i] | mask[i]) != mask[i])
+                       goto error;
+               if (last && ((spec[i] & m[i]) != (last[i] & m[i])))
+                       goto error;
        }
        return 0;
+error:
+       rte_errno = ENOTSUP;
+       return -rte_errno;
 }
 
 /**