[PATCH 5.15 059/135] RDMA/irdma: Fix possible crash due to NULL netdev in notifier

Greg Kroah-Hartman
2022-05-10T14:04:10Z

From: Mustafa Ismail <mustafa.ismail@intel.com>

commit 1c9043ae0667a43bd87beeebbdd4bed674713629 upstream.

For some net events in irdma_net_event notifier, the netdev can be NULL
which will cause a crash in rdma_vlan_dev_real_dev. Fix this by moving
all processing to the NETEVENT_NEIGH_UPDATE case where the netdev is
guaranteed to not be NULL.

Fixes: 6702bc147448 ("RDMA/irdma: Fix netdev notifications for vlan's")
Link: https://lore.kernel.org/r/20220425181703.1634-4-shiraz.saleem@intel.com
Signed-off-by: Mustafa Ismail <mustafa.ismail@intel.com>
Signed-off-by: Shiraz Saleem <shiraz.saleem@intel.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
drivers/infiniband/hw/irdma/utils.c | 21 +++++++++------------
1 file changed, 9 insertions(+), 12 deletions(-)

--- a/drivers/infiniband/hw/irdma/utils.c
+++ b/drivers/infiniband/hw/irdma/utils.c
@@ -258,18 +258,16 @@ int irdma_net_event(struct notifier_bloc
u32 local_ipaddr[4] = {};
bool ipv4 = true;

- real_dev = rdma_vlan_dev_real_dev(netdev);
- if (!real_dev)
- real_dev = netdev;
-
- ibdev = ib_device_get_by_netdev(real_dev, RDMA_DRIVER_IRDMA);
- if (!ibdev)
- return NOTIFY_DONE;
-
- iwdev = to_iwdev(ibdev);
-
switch (event) {
case NETEVENT_NEIGH_UPDATE:
+ real_dev = rdma_vlan_dev_real_dev(netdev);
+ if (!real_dev)
+ real_dev = netdev;
+ ibdev = ib_device_get_by_netdev(real_dev, RDMA_DRIVER_IRDMA);
+ if (!ibdev)
+ return NOTIFY_DONE;
+
+ iwdev = to_iwdev(ibdev);
p = (__be32 *)neigh->primary_key;
if (neigh->tbl->family == AF_INET6) {
ipv4 = false;
@@ -290,13 +288,12 @@ int irdma_net_event(struct notifier_bloc
irdma_manage_arp_cache(iwdev->rf, neigh->ha,
local_ipaddr, ipv4,
IRDMA_ARP_DELETE);
+ ib_device_put(ibdev);
break;
default:
break;
}

- ib_device_put(ibdev);
-
return NOTIFY_DONE;
}