[PATCH v2 1/2] net/mlx5: fix multiple free issue when attr ctx is NULL

[Raslan Darawsheh <rasland@mellanox.com>]

When attr_ctx is NULL it will attempt to free the list of devices twice.
Avoid double freeing the list by directly going to error handling.

Fixes: 771fa900 ("mlx5: introduce new driver for Mellanox ConnectX-4 adapters")
Cc: stable@dpdk.org

Signed-off-by: Raslan Darawsheh <rasland@mellanox.com>

---
v2 changes:
 Better handle for switch statement.
 Reword the commit log.
---
---
 drivers/net/mlx5/mlx5.c | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/drivers/net/mlx5/mlx5.c b/drivers/net/mlx5/mlx5.c
index 5190b9f..3831e3d 100644
--- a/drivers/net/mlx5/mlx5.c
+++ b/drivers/net/mlx5/mlx5.c
@@ -690,18 +690,18 @@ mlx5_pci_probe(struct rte_pci_driver *pci_drv __rte_unused,
 		break;
 	}
 	if (attr_ctx == NULL) {
-		mlx5_glue->free_device_list(list);
 		switch (err) {
 		case 0:
 			DRV_LOG(ERR,
 				"cannot access device, is mlx5_ib loaded?");
 			err = ENODEV;
-			goto error;
+			break;
 		case EINVAL:
 			DRV_LOG(ERR,
 				"cannot use device, are drivers up to date?");
-			goto error;
+			break;
 		}
+		goto error;
 	}
 	ibv_dev = list[i];
 	DRV_LOG(DEBUG, "device opened");
-- 
2.7.4