CVE-2021-47244

In the Linux kernel, the following vulnerability has been resolved:

mptcp: Fix out of bounds when parsing TCP options

The TCP option parser in mptcp (mptcp_get_options) could read one byte

out of bounds. When the length is 1, the execution flow gets into the

loop, reads one byte of the opcode, and if the opcode is neither

TCPOPT_EOL nor TCPOPT_NOP, it reads one more byte, which exceeds the

length of 1.

This fix is inspired by commit 9609dad263f8 ("ipv4: tcp_input: fix stack

out of bounds when parsing TCP options.").