From: Leon Romanovsky Date: Tue, 2 Oct 2018 08:48:03 +0000 (+0300) Subject: RDMA/restrack: Release task struct which was hold by CM_ID object X-Git-Url: http://git.cdn.openwrt.org/?a=commitdiff_plain;h=ed7a01fd3fd77f40b4ef2562b966a5decd8928d2;p=openwrt%2Fstaging%2Fblogic.git RDMA/restrack: Release task struct which was hold by CM_ID object Tracking CM_ID resource is performed in two stages: creation of cm_id and connecting it to the cma_dev. It is needed because rdma-cm protocol exports two separate user-visible calls rdma_create_id and rdma_accept. At the time of CM_ID creation, the real owner of that object is unknown yet and we need to grab task_struct. This task_struct is released or reassigned in attach phase later on. but call to rdma_destroy_id left this task_struct unreleased. Such separation is unique to CM_ID and other restrack objects initialize in one shot. It means that it is safe to use "res->valid" check to catch unfinished CM_ID flow and release task_struct for that object. Fixes: 00313983cda6 ("RDMA/nldev: provide detailed CM_ID information") Reported-by: Artemy Kovalyov Reviewed-by: Artemy Kovalyov Reviewed-by: Yossi Itigin Signed-off-by: Leon Romanovsky Reviewed-by: Steve Wise Signed-off-by: Jason Gunthorpe --- diff --git a/drivers/infiniband/core/cma.c b/drivers/infiniband/core/cma.c index f117b755c4c2..f98ddb5f4d59 100644 --- a/drivers/infiniband/core/cma.c +++ b/drivers/infiniband/core/cma.c @@ -1815,8 +1815,8 @@ void rdma_destroy_id(struct rdma_cm_id *id) mutex_lock(&id_priv->handler_mutex); mutex_unlock(&id_priv->handler_mutex); + rdma_restrack_del(&id_priv->res); if (id_priv->cma_dev) { - rdma_restrack_del(&id_priv->res); if (rdma_cap_ib_cm(id_priv->id.device, 1)) { if (id_priv->cm_id.ib) ib_destroy_cm_id(id_priv->cm_id.ib); @@ -3542,10 +3542,9 @@ int rdma_bind_addr(struct rdma_cm_id *id, struct sockaddr *addr) return 0; err2: - if (id_priv->cma_dev) { - rdma_restrack_del(&id_priv->res); + rdma_restrack_del(&id_priv->res); + if (id_priv->cma_dev) cma_release_dev(id_priv); - } err1: cma_comp_exch(id_priv, RDMA_CM_ADDR_BOUND, RDMA_CM_IDLE); return ret; diff --git a/drivers/infiniband/core/restrack.c b/drivers/infiniband/core/restrack.c index 035af568ba64..16b5f9949770 100644 --- a/drivers/infiniband/core/restrack.c +++ b/drivers/infiniband/core/restrack.c @@ -223,7 +223,7 @@ void rdma_restrack_del(struct rdma_restrack_entry *res) struct ib_device *dev; if (!res->valid) - return; + goto out; dev = res_to_dev(res); if (!dev) @@ -236,8 +236,10 @@ void rdma_restrack_del(struct rdma_restrack_entry *res) down_write(&dev->res.rwsem); hash_del(&res->node); res->valid = false; + up_write(&dev->res.rwsem); + +out: if (res->task) put_task_struct(res->task); - up_write(&dev->res.rwsem); } EXPORT_SYMBOL(rdma_restrack_del);