From a0675a386a3a68f71e831bd064082e6717b45fdc Mon Sep 17 00:00:00 2001 From: Kleber Sacilotto de Souza <klebers@linux.vnet.ibm.com> Date: Fri, 10 Aug 2012 18:25:34 +0000 Subject: [PATCH] IB/mlx4: Check iboe netdev pointer before dereferencing it Unlike other parts of the mlx4_ib code, the function build_mlx_header() doesn't check if the iboe netdev of the given port is valid before dereferencing it, which can cause a crash if the ethernet interface has already been taken down. Fix this by checking for a valid netdev pointer before using it to get the port MAC address. Signed-off-by: Kleber Sacilotto de Souza <klebers@linux.vnet.ibm.com> Signed-off-by: Roland Dreier <roland@purestorage.com> --- drivers/infiniband/hw/mlx4/qp.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) diff --git a/drivers/infiniband/hw/mlx4/qp.c b/drivers/infiniband/hw/mlx4/qp.c index a6d8ea060ea896..f585eddef4b7d5 100644 --- a/drivers/infiniband/hw/mlx4/qp.c +++ b/drivers/infiniband/hw/mlx4/qp.c @@ -1407,6 +1407,7 @@ static int build_mlx_header(struct mlx4_ib_sqp *sqp, struct ib_send_wr *wr, struct mlx4_wqe_mlx_seg *mlx = wqe; struct mlx4_wqe_inline_seg *inl = wqe + sizeof *mlx; struct mlx4_ib_ah *ah = to_mah(wr->wr.ud.ah); + struct net_device *ndev; union ib_gid sgid; u16 pkey; int send_size; @@ -1483,7 +1484,10 @@ static int build_mlx_header(struct mlx4_ib_sqp *sqp, struct ib_send_wr *wr, memcpy(sqp->ud_header.eth.dmac_h, ah->av.eth.mac, 6); /* FIXME: cache smac value? */ - smac = to_mdev(sqp->qp.ibqp.device)->iboe.netdevs[sqp->qp.port - 1]->dev_addr; + ndev = to_mdev(sqp->qp.ibqp.device)->iboe.netdevs[sqp->qp.port - 1]; + if (!ndev) + return -ENODEV; + smac = ndev->dev_addr; memcpy(sqp->ud_header.eth.smac_h, smac, 6); if (!memcmp(sqp->ud_header.eth.smac_h, sqp->ud_header.eth.dmac_h, 6)) mlx->flags |= cpu_to_be32(MLX4_WQE_CTRL_FORCE_LOOPBACK); -- GitLab