[PATCH] ethdev: validate reserved fields

[Stephen Hemminger <stephen@networkplumber.org>]

The various reserved fields added to ethdev could not be
safely used for future extensions because they were never
checked on input. Therefore ABI would be broken if these
fields were added in a future DPDK release.

Fixes: 436b3a6b6e62 ("ethdev: reserve space in main structs for extension")
Cc: thomas@monjalon.net
Signed-off-by: Stephen Hemminger <stephen@networkplumber.org>
---
 lib/ethdev/rte_ethdev.c | 41 +++++++++++++++++++++++++++++++++++++++++
 1 file changed, 41 insertions(+)

diff --git a/lib/ethdev/rte_ethdev.c b/lib/ethdev/rte_ethdev.c
index 4d0325568322..4f937a1914c9 100644
--- a/lib/ethdev/rte_ethdev.c
+++ b/lib/ethdev/rte_ethdev.c
@@ -1228,6 +1228,25 @@ rte_eth_dev_configure(uint16_t port_id, uint16_t nb_rx_q, uint16_t nb_tx_q,
 	/* Backup mtu for rollback */
 	old_mtu = dev->data->mtu;
 
+	/* fields must be zero to reserve them for future ABI changes */
+	if (dev_conf->rxmode.reserved_64s[0] != 0 ||
+	    dev_conf->rxmode.reserved_64s[1] != 0 ||
+	    dev_conf->rxmode.reserved_ptrs[0] != NULL ||
+	    dev_conf->rxmode.reserved_ptrs[1] != NULL) {
+		RTE_ETHDEV_LOG(ERR, "Rxmode reserved fields not zero\n");
+		ret = -EINVAL;
+		goto rollback;
+	}
+
+	if (dev_conf->txmode.reserved_64s[0] != 0 ||
+	    dev_conf->txmode.reserved_64s[1] != 0 ||
+	    dev_conf->txmode.reserved_ptrs[0] != NULL ||
+	    dev_conf->txmode.reserved_ptrs[1] != NULL) {
+		RTE_ETHDEV_LOG(ERR, "txmode reserved fields not zero\n");
+		ret = -EINVAL;
+		goto rollback;
+	}
+
 	ret = rte_eth_dev_info_get(port_id, &dev_info);
 	if (ret != 0)
 		goto rollback;
@@ -2003,6 +2022,14 @@ rte_eth_rx_queue_setup(uint16_t port_id, uint16_t rx_queue_id,
 	if (*dev->dev_ops->rx_queue_setup == NULL)
 		return -ENOTSUP;
 
+	if (rx_conf->reserved_64s[0] != 0 ||
+	    rx_conf->reserved_64s[1] != 0 ||
+	    rx_conf->reserved_ptrs[0] != NULL ||
+	    rx_conf->reserved_ptrs[1] != NULL) {
+		RTE_ETHDEV_LOG(ERR, "Rx conf reserved fields not zero\n");
+		return -EINVAL;
+	}
+
 	ret = rte_eth_dev_info_get(port_id, &dev_info);
 	if (ret != 0)
 		return ret;
@@ -2206,6 +2233,12 @@ rte_eth_rx_hairpin_queue_setup(uint16_t port_id, uint16_t rx_queue_id,
 		return -EINVAL;
 	}
 
+	if (conf->reserved != 0) {
+		RTE_ETHDEV_LOG(ERR,
+			       "Rx hairpin reserved field not zero\n");
+		return -EINVAL;
+	}
+
 	ret = rte_eth_dev_hairpin_capability_get(port_id, &cap);
 	if (ret != 0)
 		return ret;
@@ -2301,6 +2334,14 @@ rte_eth_tx_queue_setup(uint16_t port_id, uint16_t tx_queue_id,
 	if (*dev->dev_ops->tx_queue_setup == NULL)
 		return -ENOTSUP;
 
+	if (tx_conf->reserved_64s[0] != 0 ||
+	    tx_conf->reserved_64s[1] != 0 ||
+	    tx_conf->reserved_ptrs[0] != NULL ||
+	    tx_conf->reserved_ptrs[1] != NULL) {
+		RTE_ETHDEV_LOG(ERR, "Tx conf reserved fields not zero\n");
+		return -EINVAL;
+	}
+
 	ret = rte_eth_dev_info_get(port_id, &dev_info);
 	if (ret != 0)
 		return ret;
-- 
2.39.2