RDMA/CMA: Canonize IPv4 on IPV6 sockets properly

RDMA/CMA: Canonize IPv4 on IPV6 sockets properly

commit 285214409a9e5fceba2215461b4682b6069d8e77 upstream.

When accepting a new IPv4 connect to an IPv6 socket, the CMA tries to
canonize the address family to IPv4, but does not properly process
the listening sockaddr to get the listening port, and does not properly
set the address family of the canonized sockaddr.

Fixes: e51060f08a61 ("IB: IP address based RDMA connection manager")
Reported-By: Yotam Kenneth <yotamke@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgunthorpe@obsidianresearch.com>
Tested-by: Haggai Eran <haggaie@mellanox.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>
[lizf: Backported to 3.4:
 - there's no cma_save_ip4_info() and cma_save_ip6_info(), and instead
   we apply the changes to cma_save_net_info()]
Signed-off-by: Zefan Li <lizefan@huawei.com>