From c5c79763fac115fe827ed6a18ed94fff2432f678 Mon Sep 17 00:00:00 2001 From: Paolo Abeni Date: Fri, 29 May 2020 17:43:31 +0200 Subject: mptcp: remove msk from the token container at destruction time. Currently we remote the msk from the token container only via mptcp_close(). The MPTCP master socket can be destroyed also via other paths (e.g. if not yet accepted, when shutting down the listener socket). When we hit the latter scenario, dangling msk references are left into the token container, leading to memory corruption and/or UaF. This change addresses the issue by moving the token removal into the msk destructor. Fixes: 79c0949e9a09 ("mptcp: Add key generation and token tree") Signed-off-by: Paolo Abeni Reviewed-by: Mat Martineau Signed-off-by: David S. Miller --- net/mptcp/protocol.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'net') diff --git a/net/mptcp/protocol.c b/net/mptcp/protocol.c index 35bdfb4f3eae..34dd0e278a82 100644 --- a/net/mptcp/protocol.c +++ b/net/mptcp/protocol.c @@ -1263,7 +1263,6 @@ static void mptcp_close(struct sock *sk, long timeout) lock_sock(sk); - mptcp_token_destroy(msk->token); inet_sk_state_store(sk, TCP_CLOSE); /* be sure to always acquire the join list lock, to sync vs @@ -1461,6 +1460,7 @@ static void mptcp_destroy(struct sock *sk) { struct mptcp_sock *msk = mptcp_sk(sk); + mptcp_token_destroy(msk->token); if (msk->cached_ext) __skb_ext_put(msk->cached_ext); -- cgit v1.2.3