From c73d2e8462d0bb1d47b0e8f6a33d97ab9a154824 Mon Sep 17 00:00:00 2001 From: Carolyn Wyborny Date: Wed, 14 Sep 2016 16:24:31 -0700 Subject: [PATCH] i40e: Fix client interaction This patch fixes a problem in the client interface that was causing random stack traces in RDMA driver load and unload tests. This patch fixes the problem by checking for an existing client before trying to open it. Without this patch, there is a timing related null pointer deref. Change-ID: Ib73d30671a27f6f9770dd53b3e5292b88d6b62da Signed-off-by: Carolyn Wyborny Signed-off-by: Jeff Kirsher --- drivers/net/ethernet/intel/i40e/i40e_client.c | 29 +++++++++---------- 1 file changed, 13 insertions(+), 16 deletions(-) diff --git a/drivers/net/ethernet/intel/i40e/i40e_client.c b/drivers/net/ethernet/intel/i40e/i40e_client.c index 250db0b244b7..6ffac03d5015 100644 --- a/drivers/net/ethernet/intel/i40e/i40e_client.c +++ b/drivers/net/ethernet/intel/i40e/i40e_client.c @@ -565,7 +565,7 @@ void i40e_client_subtask(struct i40e_pf *pf) if (test_bit(__I40E_DOWN, &pf->vsi[pf->lan_vsi]->state)) continue; } else { - dev_warn(&pf->pdev->dev, "This client %s is being instanciated at probe\n", + dev_warn(&pf->pdev->dev, "This client %s is being instantiated at probe\n", client->name); } @@ -582,24 +582,21 @@ void i40e_client_subtask(struct i40e_pf *pf) dev_info(&pf->pdev->dev, "Added instance of Client %s to PF%d bus=0x%02x func=0x%02x\n", client->name, pf->hw.pf_id, pf->hw.bus.device, pf->hw.bus.func); - } - - mutex_lock(&i40e_client_instance_mutex); - /* Send an Open request to the client */ - atomic_inc(&cdev->ref_cnt); - if (client->ops && client->ops->open) - ret = client->ops->open(&cdev->lan_info, client); - atomic_dec(&cdev->ref_cnt); - if (!ret) { + mutex_lock(&i40e_client_instance_mutex); + atomic_inc(&cdev->ref_cnt); + if (client->ops && client->ops->open) + ret = client->ops->open(&cdev->lan_info, + client); + atomic_dec(&cdev->ref_cnt); + if (ret < 0) { + mutex_unlock(&i40e_client_instance_mutex); + i40e_client_del_instance(pf, client); + atomic_dec(&client->ref_cnt); + continue; + } set_bit(__I40E_CLIENT_INSTANCE_OPENED, &cdev->state); - } else { - /* remove client instance */ mutex_unlock(&i40e_client_instance_mutex); - i40e_client_del_instance(pf, client); - atomic_dec(&client->ref_cnt); - continue; } - mutex_unlock(&i40e_client_instance_mutex); } mutex_unlock(&i40e_client_mutex); }