netns: enable to specify a nsid for a get request

Combined with NETNSA_TARGET_NSID, it enables to "translate" a nsid from one
netns to a nsid of another netns.
This is useful when using NETLINK_F_LISTEN_ALL_NSID because it helps the
user to interpret a nsid received from an other netns.

Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Reviewed-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Nicolas Dichtel 2018-11-26 15:42:05 +01:00 committed by David S. Miller
parent cff478b9d9
commit 3a4f68bf66

View File

@ -797,6 +797,11 @@ static int rtnl_net_getid(struct sk_buff *skb, struct nlmsghdr *nlh,
} else if (tb[NETNSA_FD]) {
peer = get_net_ns_by_fd(nla_get_u32(tb[NETNSA_FD]));
nla = tb[NETNSA_FD];
} else if (tb[NETNSA_NSID]) {
peer = get_net_ns_by_id(net, nla_get_u32(tb[NETNSA_NSID]));
if (!peer)
peer = ERR_PTR(-ENOENT);
nla = tb[NETNSA_NSID];
} else {
NL_SET_ERR_MSG(extack, "Peer netns reference is missing");
return -EINVAL;