Commit db75a168 authored by Matthieu Baerts (NGI0)'s avatar Matthieu Baerts (NGI0) Committed by Jakub Kicinski
Browse files

mptcp: safety check before fallback 



Recently, some fallback have been initiated, while the connection was
not supposed to fallback.

Add a safety check with a warning to detect when an wrong attempt to
fallback is being done. This should help detecting any future issues
quicker.

Acked-by: default avatarPaolo Abeni <pabeni@redhat.com>
Signed-off-by: default avatarMatthieu Baerts (NGI0) <matttbe@kernel.org>
Link: https://patch.msgid.link/20250224-net-mptcp-misc-fixes-v1-3-f550f636b435@kernel.org


Signed-off-by: default avatarJakub Kicinski <kuba@kernel.org>
parent 8668860b

net/mptcp/protocol.h

+2 −0
Original line number Diff line number Diff line
@@ -1199,6 +1199,8 @@ static inline void __mptcp_do_fallback(struct mptcp_sock *msk) 
		pr_debug("TCP fallback already done (msk=%p)\n", msk);

		return;

	}

	if (WARN_ON_ONCE(!READ_ONCE(msk->allow_infinite_fallback)))

		return;

	set_bit(MPTCP_FALLBACK_DONE, &msk->flags);

}