ethdev: keep count of representor ranges in API

In its current state, the API can overflow the user-passed buffer if a new
representor range appears between function calls.

In order to solve this problem, augment the representor info structure with
the numbers of allocated and initialized ranges. This way the users of this
structure can be sure they will not overrun the buffer.

Fixes: 85e1588ca72f ("ethdev: add API to get representor info")
Cc: stable@dpdk.org
Signed-off-by: Viacheslav Galaktionov <viacheslav.galaktionov@oktetlabs.ru>
Signed-off-by: Andrew Rybchenko <andrew.rybchenko@oktetlabs.ru>
Reviewed-by: Xueming Li <xuemingl@nvidia.com>

diff --git a/drivers/net/mlx5/mlx5_ethdev.c b/drivers/net/mlx5/mlx5_ethdev.c
index 90baee5aa47ba9edce388c21e62d00f9f14e48be..c32eeefd88974d073d35640f0dbc2aaf542d59b9 100644 (file)
--- a/drivers/net/mlx5/mlx5_ethdev.c
+++ b/drivers/net/mlx5/mlx5_ethdev.c
@@ -413,9 +413,15 @@ mlx5_representor_info_get(struct rte_eth_dev *dev,
        int n_type = 4; /* Representor types, VF, HPF@VF, SF and HPF@SF. */
        int n_pf = 2; /* Number of PFs. */
        int i = 0, pf;
+       int n_entries;
 
        if (info == NULL)
                goto out;
+
+       n_entries = n_type * n_pf;
+       if ((uint32_t)n_entries > info->nb_ranges_alloc)
+               n_entries = info->nb_ranges_alloc;
+
        info->controller = 0;
        info->pf = priv->pf_bond >= 0 ? priv->pf_bond : 0;
        for (pf = 0; pf < n_pf; ++pf) {
@@ -431,6 +437,8 @@ mlx5_representor_info_get(struct rte_eth_dev *dev,
                snprintf(info->ranges[i].name,
                         sizeof(info->ranges[i].name), "pf%dvf", pf);
                i++;
+               if (i == n_entries)
+                       break;
                /* HPF range of VF type. */
                info->ranges[i].type = RTE_ETH_REPRESENTOR_VF;
                info->ranges[i].controller = 0;
@@ -443,6 +451,8 @@ mlx5_representor_info_get(struct rte_eth_dev *dev,
                snprintf(info->ranges[i].name,
                         sizeof(info->ranges[i].name), "pf%dvf", pf);
                i++;
+               if (i == n_entries)
+                       break;
                /* SF range. */
                info->ranges[i].type = RTE_ETH_REPRESENTOR_SF;
                info->ranges[i].controller = 0;
@@ -455,6 +465,8 @@ mlx5_representor_info_get(struct rte_eth_dev *dev,
                snprintf(info->ranges[i].name,
                         sizeof(info->ranges[i].name), "pf%dsf", pf);
                i++;
+               if (i == n_entries)
+                       break;
                /* HPF range of SF type. */
                info->ranges[i].type = RTE_ETH_REPRESENTOR_SF;
                info->ranges[i].controller = 0;
@@ -467,7 +479,10 @@ mlx5_representor_info_get(struct rte_eth_dev *dev,
                snprintf(info->ranges[i].name,
                         sizeof(info->ranges[i].name), "pf%dsf", pf);
                i++;
+               if (i == n_entries)
+                       break;
        }
+       info->nb_ranges = i;
 out:
        return n_type * n_pf;
 }

diff --git a/lib/ethdev/rte_ethdev.c b/lib/ethdev/rte_ethdev.c
index 6ebf52b641ab6ddf910887011360a987c79db1ac..9d95cd11e1b5f5a1e5ad764d7b33d0c49f98aa10 100644 (file)
--- a/lib/ethdev/rte_ethdev.c
+++ b/lib/ethdev/rte_ethdev.c
@@ -6002,7 +6002,8 @@ rte_eth_representor_id_get(const struct rte_eth_dev *ethdev,
                           int controller, int pf, int representor_port,
                           uint16_t *repr_id)
 {
-       int ret, n, i, count;
+       int ret, n, count;
+       uint32_t i;
        struct rte_eth_representor_info *info = NULL;
        size_t size;
 
@@ -6026,6 +6027,7 @@ rte_eth_representor_id_get(const struct rte_eth_dev *ethdev,
        info = calloc(1, size);
        if (info == NULL)
                return -ENOMEM;
+       info->nb_ranges_alloc = n;
        ret = rte_eth_representor_info_get(ethdev->data->port_id, info);
        if (ret < 0)
                goto out;
@@ -6038,7 +6040,7 @@ rte_eth_representor_id_get(const struct rte_eth_dev *ethdev,
 
        /* Locate representor ID. */
        ret = -ENOENT;
-       for (i = 0; i < n; ++i) {
+       for (i = 0; i < info->nb_ranges; ++i) {
                if (info->ranges[i].type != type)
                        continue;
                if (info->ranges[i].controller != controller)

diff --git a/lib/ethdev/rte_ethdev.h b/lib/ethdev/rte_ethdev.h
index faf3bd901d75f01bf30d6b139cdb6386d9cffc0d..d2b27c351fdb03d7298ff3e6d2b6d594706a5d37 100644 (file)
--- a/lib/ethdev/rte_ethdev.h
+++ b/lib/ethdev/rte_ethdev.h
@@ -4856,6 +4856,8 @@ struct rte_eth_representor_range {
 struct rte_eth_representor_info {
        uint16_t controller; /**< Controller ID of caller device. */
        uint16_t pf; /**< Physical function ID of caller device. */
+       uint32_t nb_ranges_alloc; /**< Size of the ranges array. */
+       uint32_t nb_ranges; /**< Number of initialized ranges. */
        struct rte_eth_representor_range ranges[];/**< Representor ID range. */
 };
 
@@ -4871,11 +4873,16 @@ struct rte_eth_representor_info {
  *   A pointer to a representor info structure.
  *   NULL to return number of range entries and allocate memory
  *   for next call to store detail.
+ *   The number of ranges that were written into this structure
+ *   will be placed into its nb_ranges field. This number cannot be
+ *   larger than the nb_ranges_alloc that by the user before calling
+ *   this function. It can be smaller than the value returned by the
+ *   function, however.
  * @return
  *   - (-ENOTSUP) if operation is not supported.
  *   - (-ENODEV) if *port_id* invalid.
  *   - (-EIO) if device is removed.
- *   - (>=0) number of representor range entries supported by device.
+ *   - (>=0) number of available representor range entries.
  */
 __rte_experimental
 int rte_eth_representor_info_get(uint16_t port_id,