mptcp: update per unacked sequence on pkt reception (cc9d2566) · Commits · 戴 / test

net/mptcp/options.c

+46 −6

Original line number	Diff line number	Diff line
		@@ -744,6 +744,46 @@ fully_established:
		return true;
		}

		static u64 expand_ack(u64 old_ack, u64 cur_ack, bool use_64bit)
		{
		u32 old_ack32, cur_ack32;

		if (use_64bit)
		return cur_ack;

		old_ack32 = (u32)old_ack;
		cur_ack32 = (u32)cur_ack;
		cur_ack = (old_ack & GENMASK_ULL(63, 32)) + cur_ack32;
		if (unlikely(before(cur_ack32, old_ack32)))
		return cur_ack + (1LL << 32);
		return cur_ack;
		}

		static void update_una(struct mptcp_sock *msk,
		struct mptcp_options_received *mp_opt)
		{
		u64 new_snd_una, snd_una, old_snd_una = atomic64_read(&msk->snd_una);
		u64 write_seq = READ_ONCE(msk->write_seq);

		/* avoid ack expansion on update conflict, to reduce the risk of
		* wrongly expanding to a future ack sequence number, which is way
		* more dangerous than missing an ack
		*/
		new_snd_una = expand_ack(old_snd_una, mp_opt->data_ack, mp_opt->ack64);

		/* ACK for data not even sent yet? Ignore. */
		if (after64(new_snd_una, write_seq))
		new_snd_una = old_snd_una;

		while (after64(new_snd_una, old_snd_una)) {
		snd_una = old_snd_una;
		old_snd_una = atomic64_cmpxchg(&msk->snd_una, snd_una,
		new_snd_una);
		if (old_snd_una == snd_una)
		break;
		}
		}

		static bool add_addr_hmac_valid(struct mptcp_sock *msk,
		struct mptcp_options_received *mp_opt)
		{
		@@ -805,6 +845,12 @@ void mptcp_incoming_options(struct sock sk, struct sk_buff skb,
		if (!mp_opt->dss)
		return;

		/* we can't wait for recvmsg() to update the ack_seq, otherwise
		* monodirectional flows will stuck
		*/
		if (mp_opt->use_ack)
		update_una(msk, mp_opt);

		mpext = skb_ext_add(skb, SKB_EXT_MPTCP);
		if (!mpext)
		return;
		@@ -831,12 +877,6 @@ void mptcp_incoming_options(struct sock sk, struct sk_buff skb,
		mpext->use_map = 1;
		}

		if (mp_opt->use_ack) {
		mpext->data_ack = mp_opt->data_ack;
		mpext->use_ack = 1;
		mpext->ack64 = mp_opt->ack64;
		}

		mpext->data_fin = mp_opt->data_fin;
		}

net/mptcp/protocol.c

+2 −0

Original line number	Diff line number	Diff line
		@@ -906,6 +906,7 @@ struct sock mptcp_sk_clone(const struct sock sk, struct request_sock *req)
		}

		msk->write_seq = subflow_req->idsn + 1;
		atomic64_set(&msk->snd_una, msk->write_seq);
		if (subflow_req->remote_key_valid) {
		msk->can_ack = true;
		msk->remote_key = subflow_req->remote_key;
		@@ -1107,6 +1108,7 @@ void mptcp_finish_connect(struct sock *ssk)
		WRITE_ONCE(msk->write_seq, subflow->idsn + 1);
		WRITE_ONCE(msk->ack_seq, ack_seq);
		WRITE_ONCE(msk->can_ack, 1);
		atomic64_set(&msk->snd_una, msk->write_seq);

		mptcp_pm_new_connection(msk, 0);
		}

net/mptcp/protocol.h

+1 −0

Original line number	Diff line number	Diff line
		@@ -147,6 +147,7 @@ struct mptcp_sock {
		u64 remote_key;
		u64 write_seq;
		u64 ack_seq;
		atomic64_t snd_una;
		u32 token;
		unsigned long flags;
		bool can_ack;

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