IB/counters: Always initialize the port counter object

Port counter objects should be initialized even if alloc_stats is
unsupported, otherwise QP bind operations in user space can trigger a NULL
pointer deference if they try to bind QP on RDMA device which doesn't
support counters.

Fixes: f34a55e497e8 ("RDMA/core: Get sum value of all counters when perform a sysfs stat read")
Link: https://lore.kernel.org/r/20190723065733.4899-11-leon@kernel.org
Signed-off-by: Parav Pandit <parav@mellanox.com>
Reviewed-by: Mark Zhang <markz@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

diff --git a/drivers/infiniband/core/counters.c b/drivers/infiniband/core/counters.c
index c7d445635476ef816855be33111dd7c8e11f52ba..45d5164e9574af247ae3bb53dd63d9791957ae18 100644 (file)
--- a/drivers/infiniband/core/counters.c
+++ b/drivers/infiniband/core/counters.c
@@ -597,7 +597,7 @@ void rdma_counter_init(struct ib_device *dev)
        struct rdma_port_counter *port_counter;
        u32 port;
 
-       if (!dev->ops.alloc_hw_stats || !dev->port_data)
+       if (!dev->port_data)
                return;
 
        rdma_for_each_port(dev, port) {
@@ -605,6 +605,9 @@ void rdma_counter_init(struct ib_device *dev)
                port_counter->mode.mode = RDMA_COUNTER_MODE_NONE;
                mutex_init(&port_counter->lock);
 
+               if (!dev->ops.alloc_hw_stats)
+                       continue;
+
                port_counter->hstats = dev->ops.alloc_hw_stats(dev, port);
                if (!port_counter->hstats)
                        goto fail;
@@ -627,9 +630,6 @@ void rdma_counter_release(struct ib_device *dev)
        struct rdma_port_counter *port_counter;
        u32 port;
 
-       if (!dev->ops.alloc_hw_stats)
-               return;
-
        rdma_for_each_port(dev, port) {
                port_counter = &dev->port_data[port].port_counter;
                kfree(port_counter->hstats);