From 5c835bb142d4013c2ab24bff5ae9f6709a39cbcf Mon Sep 17 00:00:00 2001 From: Paolo Abeni Date: Fri, 8 Jul 2022 16:36:09 -0700 Subject: mptcp: fix subflow traversal at disconnect time At disconnect time the MPTCP protocol traverse the subflows list closing each of them. In some circumstances - MPJ subflow, passive MPTCP socket, the latter operation can remove the subflow from the list, invalidating the current iterator. Address the issue using the safe list traversing helper variant. Reported-by: van fantasy Fixes: b29fcfb54cd7 ("mptcp: full disconnect implementation") Tested-by: Matthieu Baerts Reviewed-by: Mat Martineau Signed-off-by: Paolo Abeni Signed-off-by: Mat Martineau Signed-off-by: David S. Miller --- net/mptcp/protocol.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'net/mptcp/protocol.c') diff --git a/net/mptcp/protocol.c b/net/mptcp/protocol.c index cc21fafd9726..21a3ed64226e 100644 --- a/net/mptcp/protocol.c +++ b/net/mptcp/protocol.c @@ -2919,12 +2919,12 @@ static void mptcp_copy_inaddrs(struct sock *msk, const struct sock *ssk) static int mptcp_disconnect(struct sock *sk, int flags) { - struct mptcp_subflow_context *subflow; + struct mptcp_subflow_context *subflow, *tmp; struct mptcp_sock *msk = mptcp_sk(sk); inet_sk_state_store(sk, TCP_CLOSE); - mptcp_for_each_subflow(msk, subflow) { + list_for_each_entry_safe(subflow, tmp, &msk->conn_list, node) { struct sock *ssk = mptcp_subflow_tcp_sock(subflow); __mptcp_close_ssk(sk, ssk, subflow, MPTCP_CF_FASTCLOSE); -- cgit v1.2.3-59-g8ed1b