kernel: mptcp: do not queue data on closed subflows

In the Linux kernel, the following vulnerability has been resolved: mptcp: do not queue data on closed subflows Dipanjan reported a syzbot splat at close time: WARNING: CPU: 1 PID: 10818 at net/ipv4/afinet.c:153 inetsockdestruct+0x6d0/0x8e0 net/ipv4/afinet.c:153 Modules linked in: uioivshmemOE ui...