5.10-stable review patch. If anyone has any objections, please let me know.
------------------
From: Paolo Abeni pabeni@redhat.com
[ Upstream commit ba8f48f7a4d79352b764ace585b5f602ef940be0 ]
remove some of code duplications an allow preventing rescheduling on close.
Signed-off-by: Paolo Abeni pabeni@redhat.com Signed-off-by: Jakub Kicinski kuba@kernel.org Stable-dep-of: 035bca3f017e ("mptcp: fix race condition in mptcp_schedule_work()") Signed-off-by: Sasha Levin sashal@kernel.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- net/mptcp/pm.c | 3 +-- net/mptcp/protocol.c | 36 ++++++++++++++++++++++-------------- net/mptcp/protocol.h | 1 + 3 files changed, 24 insertions(+), 16 deletions(-)
--- a/net/mptcp/pm.c +++ b/net/mptcp/pm.c @@ -89,8 +89,7 @@ static bool mptcp_pm_schedule_work(struc return false;
msk->pm.status |= BIT(new_status); - if (schedule_work(&msk->work)) - sock_hold((struct sock *)msk); + mptcp_schedule_work((struct sock *)msk); return true; }
--- a/net/mptcp/protocol.c +++ b/net/mptcp/protocol.c @@ -641,9 +641,8 @@ static bool move_skbs_to_msk(struct mptc * this is not a good place to change state. Let the workqueue * do it. */ - if (mptcp_pending_data_fin(sk, NULL) && - schedule_work(&msk->work)) - sock_hold(sk); + if (mptcp_pending_data_fin(sk, NULL)) + mptcp_schedule_work(sk); }
spin_unlock_bh(&sk->sk_lock.slock); @@ -715,23 +714,32 @@ static void mptcp_reset_timer(struct soc sk_reset_timer(sk, &icsk->icsk_retransmit_timer, jiffies + tout); }
+bool mptcp_schedule_work(struct sock *sk) +{ + if (inet_sk_state_load(sk) != TCP_CLOSE && + schedule_work(&mptcp_sk(sk)->work)) { + /* each subflow already holds a reference to the sk, and the + * workqueue is invoked by a subflow, so sk can't go away here. + */ + sock_hold(sk); + return true; + } + return false; +} + void mptcp_data_acked(struct sock *sk) { mptcp_reset_timer(sk);
if ((!test_bit(MPTCP_SEND_SPACE, &mptcp_sk(sk)->flags) || - (inet_sk_state_load(sk) != TCP_ESTABLISHED)) && - schedule_work(&mptcp_sk(sk)->work)) - sock_hold(sk); + (inet_sk_state_load(sk) != TCP_ESTABLISHED))) + mptcp_schedule_work(sk); }
void mptcp_subflow_eof(struct sock *sk) { - struct mptcp_sock *msk = mptcp_sk(sk); - - if (!test_and_set_bit(MPTCP_WORK_EOF, &msk->flags) && - schedule_work(&msk->work)) - sock_hold(sk); + if (!test_and_set_bit(MPTCP_WORK_EOF, &mptcp_sk(sk)->flags)) + mptcp_schedule_work(sk); }
static void mptcp_check_for_eof(struct mptcp_sock *msk) @@ -1643,8 +1651,7 @@ static void mptcp_retransmit_handler(str mptcp_stop_timer(sk); } else { set_bit(MPTCP_WORK_RTX, &msk->flags); - if (schedule_work(&msk->work)) - sock_hold(sk); + mptcp_schedule_work(sk); } }
@@ -2503,7 +2510,8 @@ static void mptcp_release_cb(struct sock struct sock *ssk;
ssk = mptcp_subflow_recv_lookup(msk); - if (!ssk || !schedule_work(&msk->work)) + if (!ssk || sk->sk_state == TCP_CLOSE || + !schedule_work(&msk->work)) __sock_put(sk); }
--- a/net/mptcp/protocol.h +++ b/net/mptcp/protocol.h @@ -410,6 +410,7 @@ static inline bool mptcp_is_fully_establ void mptcp_rcv_space_init(struct mptcp_sock *msk, const struct sock *ssk); void mptcp_data_ready(struct sock *sk, struct sock *ssk); bool mptcp_finish_join(struct sock *sk); +bool mptcp_schedule_work(struct sock *sk); void mptcp_data_acked(struct sock *sk); void mptcp_subflow_eof(struct sock *sk); bool mptcp_update_rcv_data_fin(struct mptcp_sock *msk, u64 data_fin_seq, bool use_64bit);