syzkaller has reported a few deadlock triggered by mptcp{,6}_release. These patches address the issue in the easy way - blocking the relevant, multicast related, sockopt options on MPTCP sockets.
Note that later on net-next we are going to revert patch 1/2, as a part of a larger MPTCP sockopt implementation refactor Paolo Abeni (2): mptcp: forbit mcast-related sockopt on MPTCP sockets mptcp: revert "mptcp: provide subflow aware release function" net/mptcp/protocol.c | 100 ++++++++++++++++++++----------------------- 1 file changed, 47 insertions(+), 53 deletions(-) -- 2.26.2