[PATCH AUTOSEL 4.19 13/52] IB/mlx4: Fix race condition between catas error reset and aliasguid flows

[PATCH AUTOSEL 4.19 13/52] IB/mlx4: Fix race condition between catas error reset and aliasguid flows

[Sasha Levin]

From: Jack Morgenstein <jackm@dev.mellanox.co.il>

[ Upstream commit 587443e7773e150ae29e643ee8f41a1eed226565 ]

Code review revealed a race condition which could allow the catas error
flow to interrupt the alias guid query post mechanism at random points.
Thiis is fixed by doing cancel_delayed_work_sync() instead of
cancel_delayed_work() during the alias guid mechanism destroy flow.

Fixes: a0c64a17aba8 ("mlx4: Add alias_guid mechanism")
Signed-off-by: Jack Morgenstein <jackm@dev.mellanox.co.il>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/infiniband/hw/mlx4/alias_GUID.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/infiniband/hw/mlx4/alias_GUID.c b/drivers/infiniband/hw/mlx4/alias_GUID.c
index 155b4dfc0ae8..baab9afa9174 100644
--- a/drivers/infiniband/hw/mlx4/alias_GUID.c
+++ b/drivers/infiniband/hw/mlx4/alias_GUID.c
@@ -804,8 +804,8 @@ void mlx4_ib_destroy_alias_guid_service(struct mlx4_ib_dev *dev)
 	unsigned long flags;
 
 	for (i = 0 ; i < dev->num_ports; i++) {
-		cancel_delayed_work(&dev->sriov.alias_guid.ports_guid[i].alias_guid_work);
 		det = &sriov->alias_guid.ports_guid[i];
+		cancel_delayed_work_sync(&det->alias_guid_work);
 		spin_lock_irqsave(&sriov->alias_guid.ag_work_lock, flags);
 		while (!list_empty(&det->cb_list)) {
 			cb_ctx = list_entry(det->cb_list.next,
-- 
2.19.1

[PATCH AUTOSEL 4.19 14/52] i40iw: Avoid panic when handling the inetdev event

[Sasha Levin]

From: Feng Tang <feng.tang@intel.com>

[ Upstream commit ec4fe4bcc584b55e24e8d1768f5510a62c0fd619 ]

There is a panic reported that on a system with x722 ethernet, when doing
the operations like:

	# ip link add br0 type bridge
	# ip link set eno1 master br0
	# systemctl restart systemd-networkd

The system will panic "BUG: unable to handle kernel null pointer
dereference at 0000000000000034", with call chain:

	i40iw_inetaddr_event
	notifier_call_chain
	blocking_notifier_call_chain
	notifier_call_chain
	__inet_del_ifa
	inet_rtm_deladdr
	rtnetlink_rcv_msg
	netlink_rcv_skb
	rtnetlink_rcv
	netlink_unicast
	netlink_sendmsg
	sock_sendmsg
	__sys_sendto

It is caused by "local_ipaddr = ntohl(in->ifa_list->ifa_address)", while
the in->ifa_list is NULL.

So add a check for the "in->ifa_list == NULL" case, and skip the ARP
operation accordingly.

Signed-off-by: Feng Tang <feng.tang@intel.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/infiniband/hw/i40iw/i40iw_utils.c | 12 +++++++++++-
 1 file changed, 11 insertions(+), 1 deletion(-)

diff --git a/drivers/infiniband/hw/i40iw/i40iw_utils.c b/drivers/infiniband/hw/i40iw/i40iw_utils.c
index a9ea966877f2..dda8e79d4b27 100644
--- a/drivers/infiniband/hw/i40iw/i40iw_utils.c
+++ b/drivers/infiniband/hw/i40iw/i40iw_utils.c
@@ -173,7 +173,12 @@ int i40iw_inetaddr_event(struct notifier_block *notifier,
 
 		rcu_read_lock();
 		in = __in_dev_get_rcu(upper_dev);
-		local_ipaddr = ntohl(in->ifa_list->ifa_address);
+
+		if (!in->ifa_list)
+			local_ipaddr = 0;
+		else
+			local_ipaddr = ntohl(in->ifa_list->ifa_address);
+
 		rcu_read_unlock();
 	} else {
 		local_ipaddr = ntohl(ifa->ifa_address);
@@ -185,6 +190,11 @@ int i40iw_inetaddr_event(struct notifier_block *notifier,
 	case NETDEV_UP:
 		/* Fall through */
 	case NETDEV_CHANGEADDR:
+
+		/* Just skip if no need to handle ARP cache */
+		if (!local_ipaddr)
+			break;
+
 		i40iw_manage_arp_cache(iwdev,
 				       netdev->dev_addr,
 				       &local_ipaddr,
-- 
2.19.1