mptcp_token_get_sock() may return a mptcp socket that is in
a different net namespace than the socket that received the token value.
The mptcp syncookie code path had an explicit check for this,
this moves the test into mptcp_token_get_sock() function.
Eventually token.c should be converted to pernet storage, but
such change is not suitable for net tree.
Fixes: 2c5ebd001d ("mptcp: refactor token container")
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
ea1300b9df