CVE-2026-63867 mptcp: close TOCTOU race while computing rcv_wnd

In the Linux kernel, the following vulnerability has been resolved: mptcp: close TOCTOU race while computing rcvwnd The MPTCP output path access locklessly the MPTCP-level ackseq in multiple times, using possibly different values for the dataack in the DSS option and to compute the announced rcv...