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mptcp: annotate lockless access for RX path fields

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The following fields:

 - ack_seq
 - snd_una
 - wnd_end
 - rmem_fwd_alloc

are protected by the data lock end accessed lockless in a few
spots. Ensure ONCE annotation for write (under such lock) and for
lockless read.

Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Reviewed-by: Mat Martineau <martineau@kernel.org>
Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Paolo Abeni 2024-02-02 12:40:09 +01:00 committed by David S. Miller
parent d440a4e27a
commit 9426ce476a
2 changed files with 14 additions and 11 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

6
net/mptcp/options.c
View File

@ -1030,7 +1030,7 @@ u64 __mptcp_expand_seq(u64 old_seq, u64 cur_seq)
static void __mptcp_snd_una_update(struct mptcp_sock *msk, u64 new_snd_una) static void __mptcp_snd_una_update(struct mptcp_sock *msk, u64 new_snd_una)
{ {
msk->bytes_acked += new_snd_una - msk->snd_una; msk->bytes_acked += new_snd_una - msk->snd_una;
msk->snd_una = new_snd_una; WRITE_ONCE(msk->snd_una, new_snd_una);
} }
static void ack_update_msk(struct mptcp_sock *msk, static void ack_update_msk(struct mptcp_sock *msk,
@ -1057,7 +1057,7 @@ static void ack_update_msk(struct mptcp_sock *msk,
new_wnd_end = new_snd_una + tcp_sk(ssk)->snd_wnd; new_wnd_end = new_snd_una + tcp_sk(ssk)->snd_wnd;
if (after64(new_wnd_end, msk->wnd_end)) if (after64(new_wnd_end, msk->wnd_end))
msk->wnd_end = new_wnd_end; WRITE_ONCE(msk->wnd_end, new_wnd_end);
/* this assumes mptcp_incoming_options() is invoked after tcp_ack() */ /* this assumes mptcp_incoming_options() is invoked after tcp_ack() */
if (after64(msk->wnd_end, snd_nxt)) if (after64(msk->wnd_end, snd_nxt))
@ -1071,7 +1071,7 @@ static void ack_update_msk(struct mptcp_sock *msk,
trace_ack_update_msk(mp_opt->data_ack, trace_ack_update_msk(mp_opt->data_ack,
old_snd_una, new_snd_una, old_snd_una, new_snd_una,
new_wnd_end, msk->wnd_end); new_wnd_end, READ_ONCE(msk->wnd_end));
} }
bool mptcp_update_rcv_data_fin(struct mptcp_sock *msk, u64 data_fin_seq, bool use_64bit) bool mptcp_update_rcv_data_fin(struct mptcp_sock *msk, u64 data_fin_seq, bool use_64bit)

19
net/mptcp/protocol.c
View File

@ -410,6 +410,7 @@ static void mptcp_close_wake_up(struct sock *sk)
sk_wake_async(sk, SOCK_WAKE_WAITD, POLL_IN); sk_wake_async(sk, SOCK_WAKE_WAITD, POLL_IN);
} }
/* called under the msk socket lock */
static bool mptcp_pending_data_fin_ack(struct sock *sk) static bool mptcp_pending_data_fin_ack(struct sock *sk)
{ {
struct mptcp_sock *msk = mptcp_sk(sk); struct mptcp_sock *msk = mptcp_sk(sk);
@ -441,16 +442,17 @@ static void mptcp_check_data_fin_ack(struct sock *sk)
} }
} }
/* can be called with no lock acquired */
static bool mptcp_pending_data_fin(struct sock *sk, u64 *seq) static bool mptcp_pending_data_fin(struct sock *sk, u64 *seq)
{ {
struct mptcp_sock *msk = mptcp_sk(sk); struct mptcp_sock *msk = mptcp_sk(sk);
if (READ_ONCE(msk->rcv_data_fin) && if (READ_ONCE(msk->rcv_data_fin) &&
((1 << sk->sk_state) & ((1 << inet_sk_state_load(sk)) &
(TCPF_ESTABLISHED | TCPF_FIN_WAIT1 | TCPF_FIN_WAIT2))) { (TCPF_ESTABLISHED | TCPF_FIN_WAIT1 | TCPF_FIN_WAIT2))) {
u64 rcv_data_fin_seq = READ_ONCE(msk->rcv_data_fin_seq); u64 rcv_data_fin_seq = READ_ONCE(msk->rcv_data_fin_seq);
if (msk->ack_seq == rcv_data_fin_seq) { if (READ_ONCE(msk->ack_seq) == rcv_data_fin_seq) {
if (seq) if (seq)
*seq = rcv_data_fin_seq; *seq = rcv_data_fin_seq;
@ -748,7 +750,7 @@ static bool __mptcp_ofo_queue(struct mptcp_sock *msk)
__skb_queue_tail(&sk->sk_receive_queue, skb); __skb_queue_tail(&sk->sk_receive_queue, skb);
} }
msk->bytes_received += end_seq - msk->ack_seq; msk->bytes_received += end_seq - msk->ack_seq;
msk->ack_seq = end_seq; WRITE_ONCE(msk->ack_seq, end_seq);
moved = true; moved = true;
} }
return moved; return moved;
@ -985,6 +987,7 @@ static void dfrag_clear(struct sock *sk, struct mptcp_data_frag *dfrag)
put_page(dfrag->page); put_page(dfrag->page);
} }
/* called under both the msk socket lock and the data lock */
static void __mptcp_clean_una(struct sock *sk) static void __mptcp_clean_una(struct sock *sk)
{ {
struct mptcp_sock *msk = mptcp_sk(sk); struct mptcp_sock *msk = mptcp_sk(sk);
@ -2110,7 +2113,7 @@ static unsigned int mptcp_inq_hint(const struct sock *sk)
skb = skb_peek(&msk->receive_queue); skb = skb_peek(&msk->receive_queue);
if (skb) { if (skb) {
u64 hint_val = msk->ack_seq - MPTCP_SKB_CB(skb)->map_seq; u64 hint_val = READ_ONCE(msk->ack_seq) - MPTCP_SKB_CB(skb)->map_seq;
if (hint_val >= INT_MAX) if (hint_val >= INT_MAX)
return INT_MAX; return INT_MAX;
@ -2754,7 +2757,7 @@ static void __mptcp_init_sock(struct sock *sk)
__skb_queue_head_init(&msk->receive_queue); __skb_queue_head_init(&msk->receive_queue);
msk->out_of_order_queue = RB_ROOT; msk->out_of_order_queue = RB_ROOT;
msk->first_pending = NULL; msk->first_pending = NULL;
msk->rmem_fwd_alloc = 0; WRITE_ONCE(msk->rmem_fwd_alloc, 0);
WRITE_ONCE(msk->rmem_released, 0); WRITE_ONCE(msk->rmem_released, 0);
msk->timer_ival = TCP_RTO_MIN; msk->timer_ival = TCP_RTO_MIN;
msk->scaling_ratio = TCP_DEFAULT_SCALING_RATIO; msk->scaling_ratio = TCP_DEFAULT_SCALING_RATIO;
@ -2970,7 +2973,7 @@ static void __mptcp_destroy_sock(struct sock *sk)
sk->sk_prot->destroy(sk); sk->sk_prot->destroy(sk);
WARN_ON_ONCE(msk->rmem_fwd_alloc); WARN_ON_ONCE(READ_ONCE(msk->rmem_fwd_alloc));
WARN_ON_ONCE(msk->rmem_released); WARN_ON_ONCE(msk->rmem_released);
sk_stream_kill_queues(sk); sk_stream_kill_queues(sk);
xfrm_sk_free_policy(sk); xfrm_sk_free_policy(sk);
@ -3204,8 +3207,8 @@ struct sock *mptcp_sk_clone_init(const struct sock *sk,
WRITE_ONCE(msk->write_seq, subflow_req->idsn + 1); WRITE_ONCE(msk->write_seq, subflow_req->idsn + 1);
WRITE_ONCE(msk->snd_nxt, msk->write_seq); WRITE_ONCE(msk->snd_nxt, msk->write_seq);
msk->snd_una = msk->write_seq; WRITE_ONCE(msk->snd_una, msk->write_seq);
msk->wnd_end = msk->snd_nxt + req->rsk_rcv_wnd; WRITE_ONCE(msk->wnd_end, msk->snd_nxt + req->rsk_rcv_wnd);
msk->setsockopt_seq = mptcp_sk(sk)->setsockopt_seq; msk->setsockopt_seq = mptcp_sk(sk)->setsockopt_seq;
mptcp_init_sched(msk, mptcp_sk(sk)->sched); mptcp_init_sched(msk, mptcp_sk(sk)->sched);