[PATCH v2] infiniband: i40iw: fix potential NULL pointer dereferences

Kangjie Lu
2019-03-15T06:57:30Z

alloc_ordered_workqueue may fail and return NULL.
The fix captures the failure and handles it properly to avoid
potential NULL pointer dereferences.

Signed-off-by: Kangjie Lu <kjlu@umn.edu>
---
V2: add return value to capture the error code
---
drivers/infiniband/hw/i40iw/i40iw.h | 2 +-
drivers/infiniband/hw/i40iw/i40iw_cm.c | 19 ++++++++++++++++---
drivers/infiniband/hw/i40iw/i40iw_main.c | 5 ++++-
3 files changed, 21 insertions(+), 5 deletions(-)

diff --git a/drivers/infiniband/hw/i40iw/i40iw.h b/drivers/infiniband/hw/i40iw/i40iw.h
index 2f2b4426ded7..8feec35f95a7 100644
--- a/drivers/infiniband/hw/i40iw/i40iw.h
+++ b/drivers/infiniband/hw/i40iw/i40iw.h
@@ -552,7 +552,7 @@ enum i40iw_status_code i40iw_obj_aligned_mem(struct i40iw_device *iwdev,

void i40iw_request_reset(struct i40iw_device *iwdev);
void i40iw_destroy_rdma_device(struct i40iw_ib_device *iwibdev);
-void i40iw_setup_cm_core(struct i40iw_device *iwdev);
+int i40iw_setup_cm_core(struct i40iw_device *iwdev);
void i40iw_cleanup_cm_core(struct i40iw_cm_core *cm_core);
void i40iw_process_ceq(struct i40iw_device *, struct i40iw_ceq *iwceq);
void i40iw_process_aeq(struct i40iw_device *);
diff --git a/drivers/infiniband/hw/i40iw/i40iw_cm.c b/drivers/infiniband/hw/i40iw/i40iw_cm.c
index 206cfb0016f8..2e20786b9a57 100644
--- a/drivers/infiniband/hw/i40iw/i40iw_cm.c
+++ b/drivers/infiniband/hw/i40iw/i40iw_cm.c
@@ -3237,7 +3237,7 @@ void i40iw_receive_ilq(struct i40iw_sc_vsi *vsi, struct i40iw_puda_buf *rbuf)
* core
* @iwdev: iwarp device structure
*/
-void i40iw_setup_cm_core(struct i40iw_device *iwdev)
+int i40iw_setup_cm_core(struct i40iw_device *iwdev)
{
struct i40iw_cm_core *cm_core = &iwdev->cm_core;

@@ -3256,9 +3256,20 @@ void i40iw_setup_cm_core(struct i40iw_device *iwdev)

cm_core->event_wq = alloc_ordered_workqueue("iwewq",
WQ_MEM_RECLAIM);
+ if (!cm_core->event_wq)
+ goto error;

cm_core->disconn_wq = alloc_ordered_workqueue("iwdwq",
WQ_MEM_RECLAIM);
+ if (!cm_core->disconn_wq)
+ goto error;
+
+ return 0;
+error:
+ i40iw_cleanup_cm_core(&iwdev->cm_core);
+ i40iw_pr_err("fail to setup CM core");
+
+ return -ENOMEM;
}

/**
@@ -3278,8 +3289,10 @@ void i40iw_cleanup_cm_core(struct i40iw_cm_core *cm_core)
del_timer_sync(&cm_core->tcp_timer);
spin_unlock_irqrestore(&cm_core->ht_lock, flags);

- destroy_workqueue(cm_core->event_wq);
- destroy_workqueue(cm_core->disconn_wq);
+ if (cm_core->event_wq)
+ destroy_workqueue(cm_core->event_wq);
+ if (cm_core->disconn_wq)
+ destroy_workqueue(cm_core->disconn_wq);
}

/**
diff --git a/drivers/infiniband/hw/i40iw/i40iw_main.c b/drivers/infiniband/hw/i40iw/i40iw_main.c
index 68095f00d08f..10932baee279 100644
--- a/drivers/infiniband/hw/i40iw/i40iw_main.c
+++ b/drivers/infiniband/hw/i40iw/i40iw_main.c
@@ -1641,7 +1641,10 @@ static int i40iw_open(struct i40e_info *ldev, struct i40e_client *client)
iwdev = &hdl->device;
iwdev->hdl = hdl;
dev = &iwdev->sc_dev;
- i40iw_setup_cm_core(iwdev);
+ if (i40iw_setup_cm_core(iwdev)) {
+ kfree(iwdev->hdl);
+ return -ENOMEM;
+ }

dev->back_dev = (void *)iwdev;
iwdev->ldev = &hdl->ldev;
--
2.17.1