From d1bb64a9bfcf0aecafb37d812df716992e284d64 Mon Sep 17 00:00:00 2001 From: Bart Van Assche Date: Wed, 11 Oct 2017 10:49:02 -0700 Subject: [PATCH] RDMA/i40iw: Fix a race condition Use the proper primitives to dereference the RCU pointer upper_dev->ip_ptr. Compile-tested only. Signed-off-by: Bart Van Assche Reviewed-by: Shiraz Saleem Signed-off-by: Doug Ledford --- drivers/infiniband/hw/i40iw/i40iw_utils.c | 13 +++++++++---- 1 file changed, 9 insertions(+), 4 deletions(-) diff --git a/drivers/infiniband/hw/i40iw/i40iw_utils.c b/drivers/infiniband/hw/i40iw/i40iw_utils.c index e52dbbb4165ec..7304189b62ef8 100644 --- a/drivers/infiniband/hw/i40iw/i40iw_utils.c +++ b/drivers/infiniband/hw/i40iw/i40iw_utils.c @@ -168,11 +168,16 @@ int i40iw_inetaddr_event(struct notifier_block *notifier, if (netdev != event_netdev) return NOTIFY_DONE; - if (upper_dev) - local_ipaddr = ntohl( - ((struct in_device *)upper_dev->ip_ptr)->ifa_list->ifa_address); - else + if (upper_dev) { + struct in_device *in; + + rcu_read_lock(); + in = __in_dev_get_rcu(upper_dev); + local_ipaddr = ntohl(in->ifa_list->ifa_address); + rcu_read_unlock(); + } else { local_ipaddr = ntohl(ifa->ifa_address); + } switch (event) { case NETDEV_DOWN: action = I40IW_ARP_DELETE; -- 2.39.5