Commit 0597d0f8 authored Dec 09, 2020 by Paolo Abeni Committed by David S. Miller Dec 09, 2020

mptcp: plug subflow context memory leak



When a MPTCP listener socket is closed with unaccepted
children pending, the ULP release callback will be invoked,
but nobody will call into __mptcp_close_ssk() on the
corresponding subflow.

As a consequence, at ULP release time, the 'disposable' flag
will be cleared and the subflow context memory will be leaked.

This change addresses the issue always freeing the context if
the subflow is still in the accept queue at ULP release time.

Additionally, this fixes an incorrect code reference in the
related comment.

Note: this fix leverages the changes introduced by the previous
commit.

Fixes: e16163b6 ("mptcp: refactor shutdown and close")
Reviewed-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

parent 5b950ff4

net/mptcp/subflow.c

+3 −2

Original line number	Diff line number	Diff line
		@@ -1339,9 +1339,10 @@ static void subflow_ulp_release(struct sock *ssk)
		sk = ctx->conn;
		if (sk) {
		/* if the msk has been orphaned, keep the ctx
		* alive, will be freed by mptcp_done()
		* alive, will be freed by __mptcp_close_ssk(),
		* when the subflow is still unaccepted
		*/
		release = ctx->disposable;
		release = ctx->disposable \|\| list_empty(&ctx->node);
		sock_put(sk);
		}

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