ethdev: avoid undefined behaviour on configuration copy

memcpy() source and destination areas must not overlap and equal
pointers is the case which is really met, so handle it.

Fixes: 68b931bff287 ("ethdev: eliminate interim variable")
Cc: stable@dpdk.org
Signed-off-by: Andrew Rybchenko <arybchenko@solarflare.com>
Reviewed-by: Ferruh Yigit <ferruh.yigit@intel.com>

diff --git a/lib/librte_ethdev/rte_ethdev.c b/lib/librte_ethdev/rte_ethdev.c
index 8f48e8d..8d2ce31 100644 (file)
--- a/lib/librte_ethdev/rte_ethdev.c
+++ b/lib/librte_ethdev/rte_ethdev.c
@@ -1245,7 +1245,9 @@ rte_eth_dev_configure(uint16_t port_id, uint16_t nb_rx_q, uint16_t nb_tx_q,
         * Copy the dev_conf parameter into the dev structure.
         * rte_eth_dev_info_get() requires dev_conf, copy it before dev_info get
         */
-       memcpy(&dev->data->dev_conf, dev_conf, sizeof(dev->data->dev_conf));
+       if (dev_conf != &dev->data->dev_conf)
+               memcpy(&dev->data->dev_conf, dev_conf,
+                      sizeof(dev->data->dev_conf));
 
        ret = rte_eth_dev_info_get(port_id, &dev_info);
        if (ret != 0)