4.9-stable review patch. If anyone has any objections, please let me know.
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From: Parav Pandit parav@mellanox.com
[ Upstream commit bb7f8f199c354c4cf155b1d6d55f86eaaed7fa5a ]
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: 200298326b27 ("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 Signed-off-by: Sasha Levin alexander.levin@microsoft.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/infiniband/core/sa_query.c | 7 +++---- 1 file changed, 3 insertions(+), 4 deletions(-)
--- a/drivers/infiniband/core/sa_query.c +++ b/drivers/infiniband/core/sa_query.c @@ -1137,10 +1137,9 @@ int ib_init_ah_from_path(struct ib_devic
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();