IB/core: Fix possible crash to access NULL netdev

resolved_dev returned might be NULL as ifindex is transient number.
Ignoring NULL check of resolved_dev might crash the kernel.
Therefore perform NULL check before accessing resolved_dev.

Additionally rdma_resolve_ip_route() invokes addr_resolve() which
performs check and address translation for loopback ifindex.
Therefore, checking it again in rdma_resolve_ip_route() is not helpful.
Therefore, the code is simplified to avoid IFF_LOOPBACK check.

Fixes: 200298326b ("IB/core: Validate route when we init ah")
Reviewed-by: Daniel Jurgens <danielj@mellanox.com>
Signed-off-by: Parav Pandit <parav@mellanox.com>
Signed-off-by: Leon Romanovsky <leon@kernel.org>
Signed-off-by: Doug Ledford <dledford@redhat.com>
This commit is contained in:
Parav Pandit 2018-03-07 08:07:41 +02:00 committed by Doug Ledford
parent 942c9b6ca8
commit bb7f8f199c

View File

@ -1291,10 +1291,9 @@ int ib_init_ah_attr_from_path(struct ib_device *device, u8 port_num,
resolved_dev = dev_get_by_index(dev_addr.net,
dev_addr.bound_dev_if);
if (resolved_dev->flags & IFF_LOOPBACK) {
dev_put(resolved_dev);
resolved_dev = idev;
dev_hold(resolved_dev);
if (!resolved_dev) {
dev_put(idev);
return -ENODEV;
}
ndev = ib_get_ndev_from_path(rec);
rcu_read_lock();