4.9-stable review patch. If anyone has any objections, please let me know.
------------------ From: Shiraz Saleem <[email protected]> [ Upstream commit 871a8623d3b40221ad1103aff715dfee0aa4dacf ] Netdev notification events are de-registered only when all client iwdev instances are removed. If a single client is closed and re-opened, netdev events could arrive even before the Control Queue-Pair (CQP) is created, causing a NULL pointer dereference crash in i40iw_get_cqp_request. Fix this by allowing netdev event notification only after we have reached the INET_NOTIFIER state with respect to device initialization. Reported-by: Stefan Assmann <[email protected]> Signed-off-by: Shiraz Saleem <[email protected]> Reviewed-by: Yuval Shaia <[email protected]> Signed-off-by: Doug Ledford <[email protected]> Signed-off-by: Sasha Levin <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]> --- drivers/infiniband/hw/i40iw/i40iw_utils.c | 8 ++++++++ 1 file changed, 8 insertions(+) --- a/drivers/infiniband/hw/i40iw/i40iw_utils.c +++ b/drivers/infiniband/hw/i40iw/i40iw_utils.c @@ -159,6 +159,9 @@ int i40iw_inetaddr_event(struct notifier return NOTIFY_DONE; iwdev = &hdl->device; + if (iwdev->init_state < INET_NOTIFIER) + return NOTIFY_DONE; + netdev = iwdev->ldev->netdev; upper_dev = netdev_master_upper_dev_get(netdev); if (netdev != event_netdev) @@ -231,6 +234,9 @@ int i40iw_inet6addr_event(struct notifie return NOTIFY_DONE; iwdev = &hdl->device; + if (iwdev->init_state < INET_NOTIFIER) + return NOTIFY_DONE; + netdev = iwdev->ldev->netdev; if (netdev != event_netdev) return NOTIFY_DONE; @@ -280,6 +286,8 @@ int i40iw_net_event(struct notifier_bloc if (!iwhdl) return NOTIFY_DONE; iwdev = &iwhdl->device; + if (iwdev->init_state < INET_NOTIFIER) + return NOTIFY_DONE; p = (__be32 *)neigh->primary_key; i40iw_copy_ip_ntohl(local_ipaddr, p); if (neigh->nud_state & NUD_VALID) {

