From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Gustavo A. R. Silva" Subject: [PATCH] net/mlx5e/core/en_fs: fix pointer dereference after free in mlx5e_execute_l2_action Date: Sat, 4 Nov 2017 22:54:53 -0500 Message-ID: <20171105035453.GA10908@embeddedor.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: netdev@vger.kernel.org, linux-rdma@vger.kernel.org, linux-kernel@vger.kernel.org, "Gustavo A. R. Silva" To: Saeed Mahameed , Matan Barak , Leon Romanovsky Return-path: Content-Disposition: inline Sender: linux-kernel-owner@vger.kernel.org List-Id: netdev.vger.kernel.org hn is being kfree'd in mlx5e_del_l2_from_hash and then dereferenced by accessing hn->ai.addr Fix this by copying the MAC address into a local variable for its safe use in all possible execution paths within function mlx5e_execute_l2_action. Addresses-Coverity-ID: 1417789 Fixes: eeb66cdb6826 ("net/mlx5: Separate between E-Switch and MPFS") Signed-off-by: Gustavo A. R. Silva --- drivers/net/ethernet/mellanox/mlx5/core/en_fs.c | 13 ++++++++----- 1 file changed, 8 insertions(+), 5 deletions(-) diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en_fs.c b/drivers/net/ethernet/mellanox/mlx5/core/en_fs.c index 850cdc9..4837045 100644 --- a/drivers/net/ethernet/mellanox/mlx5/core/en_fs.c +++ b/drivers/net/ethernet/mellanox/mlx5/core/en_fs.c @@ -365,21 +365,24 @@ static void mlx5e_execute_l2_action(struct mlx5e_priv *priv, struct mlx5e_l2_hash_node *hn) { u8 action = hn->action; + u8 mac_addr[ETH_ALEN]; int l2_err = 0; + ether_addr_copy(mac_addr, hn->ai.addr); + switch (action) { case MLX5E_ACTION_ADD: mlx5e_add_l2_flow_rule(priv, &hn->ai, MLX5E_FULLMATCH); - if (!is_multicast_ether_addr(hn->ai.addr)) { - l2_err = mlx5_mpfs_add_mac(priv->mdev, hn->ai.addr); + if (!is_multicast_ether_addr(mac_addr)) { + l2_err = mlx5_mpfs_add_mac(priv->mdev, mac_addr); hn->mpfs = !l2_err; } hn->action = MLX5E_ACTION_NONE; break; case MLX5E_ACTION_DEL: - if (!is_multicast_ether_addr(hn->ai.addr) && hn->mpfs) - l2_err = mlx5_mpfs_del_mac(priv->mdev, hn->ai.addr); + if (!is_multicast_ether_addr(mac_addr) && hn->mpfs) + l2_err = mlx5_mpfs_del_mac(priv->mdev, mac_addr); mlx5e_del_l2_flow_rule(priv, &hn->ai); mlx5e_del_l2_from_hash(hn); break; @@ -387,7 +390,7 @@ static void mlx5e_execute_l2_action(struct mlx5e_priv *priv, if (l2_err) netdev_warn(priv->netdev, "MPFS, failed to %s mac %pM, err(%d)\n", - action == MLX5E_ACTION_ADD ? "add" : "del", hn->ai.addr, l2_err); + action == MLX5E_ACTION_ADD ? "add" : "del", mac_addr, l2_err); } static void mlx5e_sync_netdev_addr(struct mlx5e_priv *priv) -- 2.7.4