mlx4_en: Fix out of bounds array access

When searching for a free entry in either mlx4_register_vlan() or
mlx4_register_mac(), and there is no free entry, the loop terminates without
updating the local variable free thus causing out of array bounds access. Fix
this by adding a proper check outside the loop.

Signed-off-by: Eli Cohen <eli@mellanox.co.il>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/drivers/net/mlx4/port.c b/drivers/net/mlx4/port.c
index 606aa58..8674ad5 100644 (file)
--- a/drivers/net/mlx4/port.c
+++ b/drivers/net/mlx4/port.c
@@ -111,6 +111,12 @@ int mlx4_register_mac(struct mlx4_dev *dev, u8 port, u64 mac, int *index)
                        goto out;
                }
        }
+
+       if (free < 0) {
+               err = -ENOMEM;
+               goto out;
+       }
+
        mlx4_dbg(dev, "Free MAC index is %d\n", free);
 
        if (table->total == table->max) {
@@ -205,6 +211,11 @@ int mlx4_register_vlan(struct mlx4_dev *dev, u8 port, u16 vlan, int *index)
                }
        }
 
+       if (free < 0) {
+               err = -ENOMEM;
+               goto out;
+       }
+
        if (table->total == table->max) {
                /* No free vlan entries */
                err = -ENOSPC;