From: Parav Pandit Date: Mon, 14 May 2018 08:11:07 +0000 (+0300) Subject: IB/cm: Avoid AV ah_attr overwriting during LAP message handling X-Git-Url: http://git.lede-project.org./?a=commitdiff_plain;h=a5c57d327272bdf3a8b19686eaca2ec683449e67;p=openwrt%2Fstaging%2Fblogic.git IB/cm: Avoid AV ah_attr overwriting during LAP message handling AH attribute of the cm_id can be overwritten if LAP message is received on CM request which is in progress. This bug got introduced to avoid sleeping when spin lock is held as part of commit in Fixes tag. Therefore validate the cm_id state first and continue to perform AV ah_attr initialization. Given that Aleternative path related messages are not supported for RoCE, init_av_from_response/path is such messages are ok to be called from blocking context. Fixes: 33f93e1ebcf5 ("IB/cm: Fix sleeping while spin lock is held") Signed-off-by: Parav Pandit Signed-off-by: Leon Romanovsky Signed-off-by: Jason Gunthorpe --- diff --git a/drivers/infiniband/core/cm.c b/drivers/infiniband/core/cm.c index a92e1a5c202b..34b4defc3d1f 100644 --- a/drivers/infiniband/core/cm.c +++ b/drivers/infiniband/core/cm.c @@ -3189,12 +3189,6 @@ static int cm_lap_handler(struct cm_work *work) if (!cm_id_priv) return -EINVAL; - ret = cm_init_av_for_response(work->port, work->mad_recv_wc->wc, - work->mad_recv_wc->recv_buf.grh, - &cm_id_priv->av); - if (ret) - goto deref; - param = &work->cm_event.param.lap_rcvd; memset(&work->path[0], 0, sizeof(work->path[1])); cm_path_set_rec_type(work->port->cm_dev->ib_device, @@ -3239,10 +3233,16 @@ static int cm_lap_handler(struct cm_work *work) goto unlock; } - cm_id_priv->id.lap_state = IB_CM_LAP_RCVD; - cm_id_priv->tid = lap_msg->hdr.tid; + ret = cm_init_av_for_response(work->port, work->mad_recv_wc->wc, + work->mad_recv_wc->recv_buf.grh, + &cm_id_priv->av); + if (ret) + goto unlock; + cm_init_av_by_path(param->alternate_path, &cm_id_priv->alt_av, cm_id_priv); + cm_id_priv->id.lap_state = IB_CM_LAP_RCVD; + cm_id_priv->tid = lap_msg->hdr.tid; ret = atomic_inc_and_test(&cm_id_priv->work_count); if (!ret) list_add_tail(&work->list, &cm_id_priv->work_list);