From: Paolo Abeni pabeni@redhat.com
[ Upstream commit 5c835bb142d4013c2ab24bff5ae9f6709a39cbcf ]
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 g1042620637@gmail.com Fixes: b29fcfb54cd7 ("mptcp: full disconnect implementation") Tested-by: Matthieu Baerts matthieu.baerts@tessares.net Reviewed-by: Mat Martineau mathew.j.martineau@linux.intel.com Signed-off-by: Paolo Abeni pabeni@redhat.com Signed-off-by: Mat Martineau mathew.j.martineau@linux.intel.com Signed-off-by: David S. Miller davem@davemloft.net Signed-off-by: Sasha Levin sashal@kernel.org --- net/mptcp/protocol.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-)
--- a/net/mptcp/protocol.c +++ b/net/mptcp/protocol.c @@ -2840,12 +2840,12 @@ static void mptcp_copy_inaddrs(struct so
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);