RDMA/cma: Check existence of netdevice during port validation

BugLink: http://bugs.launchpad.net/bugs/1774063
[ Upstream commit 00db63c128dd3daf38f481371976c24d32678142 ]

If valid netdevice is not found for RoCE, GID table should not be
searched with NULL netdevice.

Doing so causes the search routines to ignore the netdev argument and may
match the wrong GID table entry if the netdev is deleted.

Fixes: abae1b71dd37 ("IB/cma: cma_validate_port should verify the port and netdevice")
Signed-off-by: Parav Pandit <parav@mellanox.com>
Reviewed-by: Mark Bloch <markb@mellanox.com>
Signed-off-by: Leon Romanovsky <leon@kernel.org>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Kamal Mostafa <kamal@canonical.com>
Signed-off-by: Khalid Elmously <khalid.elmously@canonical.com>

diff --git a/drivers/infiniband/core/cma.c b/drivers/infiniband/core/cma.c
index 2fb7f2586353e20978a56ead4690f748143dab59..7898b2e678515f257dccae44ed7b0915cdc4307e 100644 (file)
--- a/drivers/infiniband/core/cma.c
+++ b/drivers/infiniband/core/cma.c
@@ -624,11 +624,13 @@ static inline int cma_validate_port(struct ib_device *device, u8 port,
        if ((dev_type != ARPHRD_INFINIBAND) && rdma_protocol_ib(device, port))
                return ret;
 
-       if (dev_type == ARPHRD_ETHER && rdma_protocol_roce(device, port))
+       if (dev_type == ARPHRD_ETHER && rdma_protocol_roce(device, port)) {
                ndev = dev_get_by_index(&init_net, bound_if_index);
-       else
+               if (!ndev)
+                       return ret;
+       } else {
                gid_type = IB_GID_TYPE_IB;
-
+       }
 
        ret = ib_find_cached_gid_by_port(device, gid, gid_type, port,
                                         ndev, NULL);