Re: [PATCH net-next v2 5/6] mptcp: support rstreason for passive reset
Hello Mat,
On Fri, Apr 5, 2024 at 4:33 AM Mat Martineau wrote:
>
> On Thu, 4 Apr 2024, Jason Xing wrote:
>
> > From: Jason Xing
> >
> > It relys on what reset options in MPTCP does as rfc8684 says. Reusing
> > this logic can save us much energy. This patch replaces all the prior
> > NOT_SPECIFIED reasons.
> >
> > Signed-off-by: Jason Xing
> > ---
> > net/mptcp/subflow.c | 26 --
> > 1 file changed, 20 insertions(+), 6 deletions(-)
> >
> > diff --git a/net/mptcp/subflow.c b/net/mptcp/subflow.c
> > index a68d5d0f3e2a..24668d3020aa 100644
> > --- a/net/mptcp/subflow.c
> > +++ b/net/mptcp/subflow.c
> > @@ -304,7 +304,10 @@ static struct dst_entry *subflow_v4_route_req(const
> > struct sock *sk,
> >
> > dst_release(dst);
> > if (!req->syncookie)
> > - tcp_request_sock_ops.send_reset(sk, skb,
> > SK_RST_REASON_NOT_SPECIFIED);
> > + /* According to RFC 8684, 3.2. Starting a New Subflow,
> > + * we should use an "MPTCP specific error" reason code.
> > + */
> > + tcp_request_sock_ops.send_reset(sk, skb,
> > SK_RST_REASON_MPTCP_RST_EMPTCP);
>
> Hi Jason -
>
> In this case, the MPTCP reset reason is set in subflow_check_req(). Looks
> like it uses EMPTCP but that isn't guaranteed to stay the same. I think it
> would be better to extract the reset reason from the skb extension or the
> subflow context "reset_reason" field.
Good suggestions :)
>
>
> > return NULL;
> > }
> >
> > @@ -371,7 +374,10 @@ static struct dst_entry *subflow_v6_route_req(const
> > struct sock *sk,
> >
> > dst_release(dst);
> > if (!req->syncookie)
> > - tcp6_request_sock_ops.send_reset(sk, skb,
> > SK_RST_REASON_NOT_SPECIFIED);
> > + /* According to RFC 8684, 3.2. Starting a New Subflow,
> > + * we should use an "MPTCP specific error" reason code.
> > + */
> > + tcp6_request_sock_ops.send_reset(sk, skb,
> > SK_RST_REASON_MPTCP_RST_EMPTCP);
>
> Same issue here.
Got it.
>
> > return NULL;
> > }
> > #endif
> > @@ -778,6 +784,7 @@ static struct sock *subflow_syn_recv_sock(const struct
> > sock *sk,
> > bool fallback, fallback_is_fatal;
> > struct mptcp_sock *owner;
> > struct sock *child;
> > + int reason;
> >
> > pr_debug("listener=%p, req=%p, conn=%p", listener, req,
> > listener->conn);
> >
> > @@ -833,7 +840,8 @@ static struct sock *subflow_syn_recv_sock(const struct
> > sock *sk,
> >*/
> > if (!ctx || fallback) {
> > if (fallback_is_fatal) {
> > - subflow_add_reset_reason(skb,
> > MPTCP_RST_EMPTCP);
> > + reason = MPTCP_RST_EMPTCP;
> > + subflow_add_reset_reason(skb, reason);
> > goto dispose_child;
> > }
> > goto fallback;
> > @@ -861,7 +869,8 @@ static struct sock *subflow_syn_recv_sock(const struct
> > sock *sk,
> > } else if (ctx->mp_join) {
> > owner = subflow_req->msk;
> > if (!owner) {
> > - subflow_add_reset_reason(skb,
> > MPTCP_RST_EPROHIBIT);
> > + reason = MPTCP_RST_EPROHIBIT;
> > + subflow_add_reset_reason(skb, reason);
> > goto dispose_child;
> > }
> >
> > @@ -875,13 +884,18 @@ static struct sock *subflow_syn_recv_sock(const
> > struct sock *sk,
> >ntohs(inet_sk((struct sock
> > *)owner)->inet_sport));
> > if (!mptcp_pm_sport_in_anno_list(owner, sk)) {
> > SUBFLOW_REQ_INC_STATS(req,
> > MPTCP_MIB_MISMATCHPORTACKRX);
> > + reason = MPTCP_RST_EUNSPEC;
>
> I think the MPTCP code here should have been using MPTCP_RST_EPROHIBIT.
I'll update in the V2 of the patch.
Thanks,
Jason
Re: [PATCH net-next v2 5/6] mptcp: support rstreason for passive reset
On Thu, 4 Apr 2024, Jason Xing wrote:
From: Jason Xing
It relys on what reset options in MPTCP does as rfc8684 says. Reusing
this logic can save us much energy. This patch replaces all the prior
NOT_SPECIFIED reasons.
Signed-off-by: Jason Xing
---
net/mptcp/subflow.c | 26 --
1 file changed, 20 insertions(+), 6 deletions(-)
diff --git a/net/mptcp/subflow.c b/net/mptcp/subflow.c
index a68d5d0f3e2a..24668d3020aa 100644
--- a/net/mptcp/subflow.c
+++ b/net/mptcp/subflow.c
@@ -304,7 +304,10 @@ static struct dst_entry *subflow_v4_route_req(const struct
sock *sk,
dst_release(dst);
if (!req->syncookie)
- tcp_request_sock_ops.send_reset(sk, skb,
SK_RST_REASON_NOT_SPECIFIED);
+ /* According to RFC 8684, 3.2. Starting a New Subflow,
+* we should use an "MPTCP specific error" reason code.
+*/
+ tcp_request_sock_ops.send_reset(sk, skb,
SK_RST_REASON_MPTCP_RST_EMPTCP);
Hi Jason -
In this case, the MPTCP reset reason is set in subflow_check_req(). Looks
like it uses EMPTCP but that isn't guaranteed to stay the same. I think it
would be better to extract the reset reason from the skb extension or the
subflow context "reset_reason" field.
return NULL;
}
@@ -371,7 +374,10 @@ static struct dst_entry *subflow_v6_route_req(const struct
sock *sk,
dst_release(dst);
if (!req->syncookie)
- tcp6_request_sock_ops.send_reset(sk, skb,
SK_RST_REASON_NOT_SPECIFIED);
+ /* According to RFC 8684, 3.2. Starting a New Subflow,
+* we should use an "MPTCP specific error" reason code.
+*/
+ tcp6_request_sock_ops.send_reset(sk, skb,
SK_RST_REASON_MPTCP_RST_EMPTCP);
Same issue here.
return NULL;
}
#endif
@@ -778,6 +784,7 @@ static struct sock *subflow_syn_recv_sock(const struct sock
*sk,
bool fallback, fallback_is_fatal;
struct mptcp_sock *owner;
struct sock *child;
+ int reason;
pr_debug("listener=%p, req=%p, conn=%p", listener, req, listener->conn);
@@ -833,7 +840,8 @@ static struct sock *subflow_syn_recv_sock(const struct sock
*sk,
*/
if (!ctx || fallback) {
if (fallback_is_fatal) {
- subflow_add_reset_reason(skb, MPTCP_RST_EMPTCP);
+ reason = MPTCP_RST_EMPTCP;
+ subflow_add_reset_reason(skb, reason);
goto dispose_child;
}
goto fallback;
@@ -861,7 +869,8 @@ static struct sock *subflow_syn_recv_sock(const struct sock
*sk,
} else if (ctx->mp_join) {
owner = subflow_req->msk;
if (!owner) {
- subflow_add_reset_reason(skb,
MPTCP_RST_EPROHIBIT);
+ reason = MPTCP_RST_EPROHIBIT;
+ subflow_add_reset_reason(skb, reason);
goto dispose_child;
}
@@ -875,13 +884,18 @@ static struct sock *subflow_syn_recv_sock(const struct
sock *sk,
ntohs(inet_sk((struct sock
*)owner)->inet_sport));
if (!mptcp_pm_sport_in_anno_list(owner, sk)) {
SUBFLOW_REQ_INC_STATS(req,
MPTCP_MIB_MISMATCHPORTACKRX);
+ reason = MPTCP_RST_EUNSPEC;
I think the MPTCP code here should have been using MPTCP_RST_EPROHIBIT.
- Mat
goto dispose_child;
}
SUBFLOW_REQ_INC_STATS(req,
MPTCP_MIB_JOINPORTACKRX);
}
- if (!mptcp_finish_join(child))
+ if (!mptcp_finish_join(child)) {
+ struct mptcp_subflow_context *subflow =
mptcp_subflow_ctx(sk);
+
+ reason = subflow->reset_reason;
goto dispose_child;
+ }
SUBFLOW_REQ_INC_STATS(req, MPTCP_MIB_JOINACKRX);
tcp_rsk(req)->drop_req = true;
@@ -901,7 +915,7 @@ static struct sock *subflow_syn_recv_sock(const struct sock
*sk,
tcp_rsk(req)->drop_req = true;
inet_csk_prepare_for_destroy_sock(child);
tcp_done(child);
- req->rsk_ops->send_reset(sk, skb, SK_RST_REASON_NOT_SPECIFIED);
+ req->rsk_ops->send_reset(sk, skb, convert_mptcp_reason(reason));
/* The last child reference will be released by the caller */
return child;
--
2.37.3
[PATCH net-next v2 6/6] rstreason: make it work in trace world
From: Jason Xing
At last, we should let it work by introducing this reset reason in
trace world.
One of the possible expected outputs is:
... tcp_send_reset: skbaddr=xxx skaddr=xxx src=xxx dest=xxx
state=TCP_ESTABLISHED reason=NOT_SPECIFIED
Signed-off-by: Jason Xing
---
include/trace/events/tcp.h | 37 +
net/ipv4/tcp_ipv4.c| 2 +-
net/ipv4/tcp_output.c | 2 +-
net/ipv6/tcp_ipv6.c| 2 +-
4 files changed, 36 insertions(+), 7 deletions(-)
diff --git a/include/trace/events/tcp.h b/include/trace/events/tcp.h
index 5c04a61a11c2..9bed9e63c9c5 100644
--- a/include/trace/events/tcp.h
+++ b/include/trace/events/tcp.h
@@ -11,6 +11,7 @@
#include
#include
#include
+#include
/*
* tcp event with arguments sk and skb
@@ -74,20 +75,38 @@ DEFINE_EVENT(tcp_event_sk_skb, tcp_retransmit_skb,
TP_ARGS(sk, skb)
);
+#undef FN1
+#define FN1(reason)TRACE_DEFINE_ENUM(SK_RST_REASON_##reason);
+#undef FN2
+#define FN2(reason)TRACE_DEFINE_ENUM(SKB_DROP_REASON_##reason);
+DEFINE_RST_REASON(FN1, FN1)
+
+#undef FN1
+#undef FNe1
+#define FN1(reason){ SK_RST_REASON_##reason, #reason },
+#define FNe1(reason) { SK_RST_REASON_##reason, #reason }
+
+#undef FN2
+#undef FNe2
+#define FN2(reason){ SKB_DROP_REASON_##reason, #reason },
+#define FNe2(reason) { SKB_DROP_REASON_##reason, #reason }
/*
* skb of trace_tcp_send_reset is the skb that caused RST. In case of
* active reset, skb should be NULL
*/
TRACE_EVENT(tcp_send_reset,
- TP_PROTO(const struct sock *sk, const struct sk_buff *skb),
+ TP_PROTO(const struct sock *sk,
+const struct sk_buff *skb,
+const int reason),
- TP_ARGS(sk, skb),
+ TP_ARGS(sk, skb, reason),
TP_STRUCT__entry(
__field(const void *, skbaddr)
__field(const void *, skaddr)
__field(int, state)
+ __field(int, reason)
__array(__u8, saddr, sizeof(struct sockaddr_in6))
__array(__u8, daddr, sizeof(struct sockaddr_in6))
),
@@ -113,14 +132,24 @@ TRACE_EVENT(tcp_send_reset,
*/
TP_STORE_ADDR_PORTS_SKB(skb, th, entry->daddr,
entry->saddr);
}
+ __entry->reason = reason;
),
- TP_printk("skbaddr=%p skaddr=%p src=%pISpc dest=%pISpc state=%s",
+ TP_printk("skbaddr=%p skaddr=%p src=%pISpc dest=%pISpc state=%s
reason=%s",
__entry->skbaddr, __entry->skaddr,
__entry->saddr, __entry->daddr,
- __entry->state ? show_tcp_state_name(__entry->state) :
"UNKNOWN")
+ __entry->state ? show_tcp_state_name(__entry->state) :
"UNKNOWN",
+ __entry->reason < RST_REASON_START ?
+ __print_symbolic(__entry->reason,
DEFINE_DROP_REASON(FN2, FNe2)) :
+ __print_symbolic(__entry->reason,
DEFINE_RST_REASON(FN1, FNe1)))
);
+#undef FN1
+#undef FNe1
+
+#undef FN2
+#undef FNe2
+
/*
* tcp event with arguments sk
*
diff --git a/net/ipv4/tcp_ipv4.c b/net/ipv4/tcp_ipv4.c
index 1ae2716f0c34..9c52a4a74842 100644
--- a/net/ipv4/tcp_ipv4.c
+++ b/net/ipv4/tcp_ipv4.c
@@ -871,7 +871,7 @@ static void tcp_v4_send_reset(const struct sock *sk, struct
sk_buff *skb,
if (sk)
arg.bound_dev_if = sk->sk_bound_dev_if;
- trace_tcp_send_reset(sk, skb);
+ trace_tcp_send_reset(sk, skb, reason);
BUILD_BUG_ON(offsetof(struct sock, sk_bound_dev_if) !=
offsetof(struct inet_timewait_sock, tw_bound_dev_if));
diff --git a/net/ipv4/tcp_output.c b/net/ipv4/tcp_output.c
index 18fbbad2028a..d5a7ecfcc1b3 100644
--- a/net/ipv4/tcp_output.c
+++ b/net/ipv4/tcp_output.c
@@ -3608,7 +3608,7 @@ void tcp_send_active_reset(struct sock *sk, gfp_t
priority, int reason)
/* skb of trace_tcp_send_reset() keeps the skb that caused RST,
* skb here is different to the troublesome skb, so use NULL
*/
- trace_tcp_send_reset(sk, NULL);
+ trace_tcp_send_reset(sk, NULL, SK_RST_REASON_NOT_SPECIFIED);
}
/* Send a crossed SYN-ACK during socket establishment.
diff --git a/net/ipv6/tcp_ipv6.c b/net/ipv6/tcp_ipv6.c
index 6889ea70c760..3c995eff6e52 100644
--- a/net/ipv6/tcp_ipv6.c
+++ b/net/ipv6/tcp_ipv6.c
@@ -1131,7 +1131,7 @@ static void tcp_v6_send_reset(const struct sock *sk,
struct sk_buff *skb,
label = ip6_flowlabel(ipv6h);
}
- trace_tcp_send_reset(sk, skb);
+ trace_tcp_send_reset(sk, skb, reason);
tcp_v6_send_response(sk, skb, seq, ack_seq, 0, 0, 0, oif, 1,
ipv6_get_dsfield(ipv6h), label, priority, txhash,
--
2.37.3
[PATCH net-next v2 5/6] mptcp: support rstreason for passive reset
From: Jason Xing
It relys on what reset options in MPTCP does as rfc8684 says. Reusing
this logic can save us much energy. This patch replaces all the prior
NOT_SPECIFIED reasons.
Signed-off-by: Jason Xing
---
net/mptcp/subflow.c | 26 --
1 file changed, 20 insertions(+), 6 deletions(-)
diff --git a/net/mptcp/subflow.c b/net/mptcp/subflow.c
index a68d5d0f3e2a..24668d3020aa 100644
--- a/net/mptcp/subflow.c
+++ b/net/mptcp/subflow.c
@@ -304,7 +304,10 @@ static struct dst_entry *subflow_v4_route_req(const struct
sock *sk,
dst_release(dst);
if (!req->syncookie)
- tcp_request_sock_ops.send_reset(sk, skb,
SK_RST_REASON_NOT_SPECIFIED);
+ /* According to RFC 8684, 3.2. Starting a New Subflow,
+* we should use an "MPTCP specific error" reason code.
+*/
+ tcp_request_sock_ops.send_reset(sk, skb,
SK_RST_REASON_MPTCP_RST_EMPTCP);
return NULL;
}
@@ -371,7 +374,10 @@ static struct dst_entry *subflow_v6_route_req(const struct
sock *sk,
dst_release(dst);
if (!req->syncookie)
- tcp6_request_sock_ops.send_reset(sk, skb,
SK_RST_REASON_NOT_SPECIFIED);
+ /* According to RFC 8684, 3.2. Starting a New Subflow,
+* we should use an "MPTCP specific error" reason code.
+*/
+ tcp6_request_sock_ops.send_reset(sk, skb,
SK_RST_REASON_MPTCP_RST_EMPTCP);
return NULL;
}
#endif
@@ -778,6 +784,7 @@ static struct sock *subflow_syn_recv_sock(const struct sock
*sk,
bool fallback, fallback_is_fatal;
struct mptcp_sock *owner;
struct sock *child;
+ int reason;
pr_debug("listener=%p, req=%p, conn=%p", listener, req, listener->conn);
@@ -833,7 +840,8 @@ static struct sock *subflow_syn_recv_sock(const struct sock
*sk,
*/
if (!ctx || fallback) {
if (fallback_is_fatal) {
- subflow_add_reset_reason(skb, MPTCP_RST_EMPTCP);
+ reason = MPTCP_RST_EMPTCP;
+ subflow_add_reset_reason(skb, reason);
goto dispose_child;
}
goto fallback;
@@ -861,7 +869,8 @@ static struct sock *subflow_syn_recv_sock(const struct sock
*sk,
} else if (ctx->mp_join) {
owner = subflow_req->msk;
if (!owner) {
- subflow_add_reset_reason(skb,
MPTCP_RST_EPROHIBIT);
+ reason = MPTCP_RST_EPROHIBIT;
+ subflow_add_reset_reason(skb, reason);
goto dispose_child;
}
@@ -875,13 +884,18 @@ static struct sock *subflow_syn_recv_sock(const struct
sock *sk,
ntohs(inet_sk((struct sock
*)owner)->inet_sport));
if (!mptcp_pm_sport_in_anno_list(owner, sk)) {
SUBFLOW_REQ_INC_STATS(req,
MPTCP_MIB_MISMATCHPORTACKRX);
+ reason = MPTCP_RST_EUNSPEC;
goto dispose_child;
}
SUBFLOW_REQ_INC_STATS(req,
MPTCP_MIB_JOINPORTACKRX);
}
- if (!mptcp_finish_join(child))
+ if (!mptcp_finish_join(child)) {
+ struct mptcp_subflow_context *subflow =
mptcp_subflow_ctx(sk);
+
+ reason = subflow->reset_reason;
goto dispose_child;
+ }
SUBFLOW_REQ_INC_STATS(req, MPTCP_MIB_JOINACKRX);
tcp_rsk(req)->drop_req = true;
@@ -901,7 +915,7 @@ static struct sock *subflow_syn_recv_sock(const struct sock
*sk,
tcp_rsk(req)->drop_req = true;
inet_csk_prepare_for_destroy_sock(child);
tcp_done(child);
- req->rsk_ops->send_reset(sk, skb, SK_RST_REASON_NOT_SPECIFIED);
+ req->rsk_ops->send_reset(sk, skb, convert_mptcp_reason(reason));
/* The last child reference will be released by the caller */
return child;
--
2.37.3
[PATCH net-next v2 4/6] tcp: support rstreason for passive reset
From: Jason Xing
Reuse the dropreason logic to show the exact reason of tcp reset,
so we don't need to implement those duplicated reset reasons.
This patch replaces all the prior NOT_SPECIFIED reasons.
Signed-off-by: Jason Xing
---
net/ipv4/tcp_ipv4.c | 8
net/ipv6/tcp_ipv6.c | 8
2 files changed, 8 insertions(+), 8 deletions(-)
diff --git a/net/ipv4/tcp_ipv4.c b/net/ipv4/tcp_ipv4.c
index d8d98db8f58e..1ae2716f0c34 100644
--- a/net/ipv4/tcp_ipv4.c
+++ b/net/ipv4/tcp_ipv4.c
@@ -1935,7 +1935,7 @@ int tcp_v4_do_rcv(struct sock *sk, struct sk_buff *skb)
return 0;
reset:
- tcp_v4_send_reset(rsk, skb, SK_RST_REASON_NOT_SPECIFIED);
+ tcp_v4_send_reset(rsk, skb, reason);
discard:
kfree_skb_reason(skb, reason);
/* Be careful here. If this function gets more complicated and
@@ -2280,7 +2280,7 @@ int tcp_v4_rcv(struct sk_buff *skb)
} else {
drop_reason = tcp_child_process(sk, nsk, skb);
if (drop_reason) {
- tcp_v4_send_reset(nsk, skb,
SK_RST_REASON_NOT_SPECIFIED);
+ tcp_v4_send_reset(nsk, skb, drop_reason);
goto discard_and_relse;
}
sock_put(sk);
@@ -2358,7 +2358,7 @@ int tcp_v4_rcv(struct sk_buff *skb)
bad_packet:
__TCP_INC_STATS(net, TCP_MIB_INERRS);
} else {
- tcp_v4_send_reset(NULL, skb, SK_RST_REASON_NOT_SPECIFIED);
+ tcp_v4_send_reset(NULL, skb, drop_reason);
}
discard_it:
@@ -2409,7 +2409,7 @@ int tcp_v4_rcv(struct sk_buff *skb)
tcp_v4_timewait_ack(sk, skb);
break;
case TCP_TW_RST:
- tcp_v4_send_reset(sk, skb, SK_RST_REASON_NOT_SPECIFIED);
+ tcp_v4_send_reset(sk, skb, drop_reason);
inet_twsk_deschedule_put(inet_twsk(sk));
goto discard_it;
case TCP_TW_SUCCESS:;
diff --git a/net/ipv6/tcp_ipv6.c b/net/ipv6/tcp_ipv6.c
index 7e591521b193..6889ea70c760 100644
--- a/net/ipv6/tcp_ipv6.c
+++ b/net/ipv6/tcp_ipv6.c
@@ -1678,7 +1678,7 @@ int tcp_v6_do_rcv(struct sock *sk, struct sk_buff *skb)
return 0;
reset:
- tcp_v6_send_reset(sk, skb, SK_RST_REASON_NOT_SPECIFIED);
+ tcp_v6_send_reset(sk, skb, reason);
discard:
if (opt_skb)
__kfree_skb(opt_skb);
@@ -1864,7 +1864,7 @@ INDIRECT_CALLABLE_SCOPE int tcp_v6_rcv(struct sk_buff
*skb)
} else {
drop_reason = tcp_child_process(sk, nsk, skb);
if (drop_reason) {
- tcp_v6_send_reset(nsk, skb,
SK_RST_REASON_NOT_SPECIFIED);
+ tcp_v6_send_reset(nsk, skb, drop_reason);
goto discard_and_relse;
}
sock_put(sk);
@@ -1940,7 +1940,7 @@ INDIRECT_CALLABLE_SCOPE int tcp_v6_rcv(struct sk_buff
*skb)
bad_packet:
__TCP_INC_STATS(net, TCP_MIB_INERRS);
} else {
- tcp_v6_send_reset(NULL, skb, SK_RST_REASON_NOT_SPECIFIED);
+ tcp_v6_send_reset(NULL, skb, drop_reason);
}
discard_it:
@@ -1995,7 +1995,7 @@ INDIRECT_CALLABLE_SCOPE int tcp_v6_rcv(struct sk_buff
*skb)
tcp_v6_timewait_ack(sk, skb);
break;
case TCP_TW_RST:
- tcp_v6_send_reset(sk, skb, SK_RST_REASON_NOT_SPECIFIED);
+ tcp_v6_send_reset(sk, skb, drop_reason);
inet_twsk_deschedule_put(inet_twsk(sk));
goto discard_it;
case TCP_TW_SUCCESS:
--
2.37.3
[PATCH net-next v2 3/6] rstreason: prepare for active reset
From: Jason Xing
Like what we did to passive reset:
only passing possible reset reason in each active reset path.
No functional changes.
Signed-off-by: Jason Xing
---
include/net/tcp.h | 2 +-
net/ipv4/tcp.c| 15 ++-
net/ipv4/tcp_output.c | 2 +-
net/ipv4/tcp_timer.c | 9 ++---
net/mptcp/protocol.c | 4 +++-
net/mptcp/subflow.c | 5 +++--
6 files changed, 24 insertions(+), 13 deletions(-)
diff --git a/include/net/tcp.h b/include/net/tcp.h
index 9ab5b37e9d53..67ab4dbf7805 100644
--- a/include/net/tcp.h
+++ b/include/net/tcp.h
@@ -667,7 +667,7 @@ int tcp_fragment(struct sock *sk, enum tcp_queue tcp_queue,
void tcp_send_probe0(struct sock *);
int tcp_write_wakeup(struct sock *, int mib);
void tcp_send_fin(struct sock *sk);
-void tcp_send_active_reset(struct sock *sk, gfp_t priority);
+void tcp_send_active_reset(struct sock *sk, gfp_t priority, int reason);
int tcp_send_synack(struct sock *);
void tcp_push_one(struct sock *, unsigned int mss_now);
void __tcp_send_ack(struct sock *sk, u32 rcv_nxt);
diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c
index e767721b3a58..eacfe0012977 100644
--- a/net/ipv4/tcp.c
+++ b/net/ipv4/tcp.c
@@ -275,6 +275,7 @@
#include
#include
#include
+#include
#include
#include
@@ -2805,7 +2806,8 @@ void __tcp_close(struct sock *sk, long timeout)
/* Unread data was tossed, zap the connection. */
NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPABORTONCLOSE);
tcp_set_state(sk, TCP_CLOSE);
- tcp_send_active_reset(sk, sk->sk_allocation);
+ tcp_send_active_reset(sk, sk->sk_allocation,
+ SK_RST_REASON_NOT_SPECIFIED);
} else if (sock_flag(sk, SOCK_LINGER) && !sk->sk_lingertime) {
/* Check zero linger _after_ checking for unread data. */
sk->sk_prot->disconnect(sk, 0);
@@ -2879,7 +2881,8 @@ void __tcp_close(struct sock *sk, long timeout)
struct tcp_sock *tp = tcp_sk(sk);
if (READ_ONCE(tp->linger2) < 0) {
tcp_set_state(sk, TCP_CLOSE);
- tcp_send_active_reset(sk, GFP_ATOMIC);
+ tcp_send_active_reset(sk, GFP_ATOMIC,
+ SK_RST_REASON_NOT_SPECIFIED);
__NET_INC_STATS(sock_net(sk),
LINUX_MIB_TCPABORTONLINGER);
} else {
@@ -2897,7 +2900,8 @@ void __tcp_close(struct sock *sk, long timeout)
if (sk->sk_state != TCP_CLOSE) {
if (tcp_check_oom(sk, 0)) {
tcp_set_state(sk, TCP_CLOSE);
- tcp_send_active_reset(sk, GFP_ATOMIC);
+ tcp_send_active_reset(sk, GFP_ATOMIC,
+ SK_RST_REASON_NOT_SPECIFIED);
__NET_INC_STATS(sock_net(sk),
LINUX_MIB_TCPABORTONMEMORY);
} else if (!check_net(sock_net(sk))) {
@@ -3001,7 +3005,7 @@ int tcp_disconnect(struct sock *sk, int flags)
/* The last check adjusts for discrepancy of Linux wrt. RFC
* states
*/
- tcp_send_active_reset(sk, gfp_any());
+ tcp_send_active_reset(sk, gfp_any(),
SK_RST_REASON_NOT_SPECIFIED);
WRITE_ONCE(sk->sk_err, ECONNRESET);
} else if (old_state == TCP_SYN_SENT)
WRITE_ONCE(sk->sk_err, ECONNRESET);
@@ -4557,7 +4561,8 @@ int tcp_abort(struct sock *sk, int err)
smp_wmb();
sk_error_report(sk);
if (tcp_need_reset(sk->sk_state))
- tcp_send_active_reset(sk, GFP_ATOMIC);
+ tcp_send_active_reset(sk, GFP_ATOMIC,
+ SK_RST_REASON_NOT_SPECIFIED);
tcp_done(sk);
}
diff --git a/net/ipv4/tcp_output.c b/net/ipv4/tcp_output.c
index e3167ad96567..18fbbad2028a 100644
--- a/net/ipv4/tcp_output.c
+++ b/net/ipv4/tcp_output.c
@@ -3583,7 +3583,7 @@ void tcp_send_fin(struct sock *sk)
* was unread data in the receive queue. This behavior is recommended
* by RFC 2525, section 2.17. -DaveM
*/
-void tcp_send_active_reset(struct sock *sk, gfp_t priority)
+void tcp_send_active_reset(struct sock *sk, gfp_t priority, int reason)
{
struct sk_buff *skb;
diff --git a/net/ipv4/tcp_timer.c b/net/ipv4/tcp_timer.c
index 976db57b95d4..83fe7f62f7f1 100644
--- a/net/ipv4/tcp_timer.c
+++ b/net/ipv4/tcp_timer.c
@@ -22,6 +22,7 @@
#include
#include
#include
+#include
static u32 tcp_clamp_rto_to_user_timeout(const struct sock *sk)
{
@@ -127,7 +128,8 @@ static int tcp_out_of_resources(struct sock *sk, bool
do_reset)
(!tp->snd_wnd && !tp->packets_out))
do_reset = true;
if (do_reset)
-
[PATCH net-next v2 2/6] rstreason: prepare for passive reset
From: Jason Xing
Adjust the paramenter and support passing reason of reset which
is for now NOT_SPECIFIED. No functional changes.
Signed-off-by: Jason Xing
---
include/net/request_sock.h | 3 ++-
net/dccp/ipv4.c| 10 ++
net/dccp/ipv6.c| 10 ++
net/dccp/minisocks.c | 3 ++-
net/ipv4/tcp_ipv4.c| 12 +++-
net/ipv4/tcp_minisocks.c | 3 ++-
net/ipv6/tcp_ipv6.c| 15 +--
net/mptcp/subflow.c| 8 +---
8 files changed, 39 insertions(+), 25 deletions(-)
diff --git a/include/net/request_sock.h b/include/net/request_sock.h
index 004e651e6067..93f9fee7e52f 100644
--- a/include/net/request_sock.h
+++ b/include/net/request_sock.h
@@ -34,7 +34,8 @@ struct request_sock_ops {
void(*send_ack)(const struct sock *sk, struct sk_buff *skb,
struct request_sock *req);
void(*send_reset)(const struct sock *sk,
- struct sk_buff *skb);
+ struct sk_buff *skb,
+ int reason);
void(*destructor)(struct request_sock *req);
void(*syn_ack_timeout)(const struct request_sock *req);
};
diff --git a/net/dccp/ipv4.c b/net/dccp/ipv4.c
index 9fc9cea4c251..11b8d14be3e2 100644
--- a/net/dccp/ipv4.c
+++ b/net/dccp/ipv4.c
@@ -24,6 +24,7 @@
#include
#include
#include
+#include
#include "ackvec.h"
#include "ccid.h"
@@ -521,7 +522,8 @@ static int dccp_v4_send_response(const struct sock *sk,
struct request_sock *req
return err;
}
-static void dccp_v4_ctl_send_reset(const struct sock *sk, struct sk_buff
*rxskb)
+static void dccp_v4_ctl_send_reset(const struct sock *sk, struct sk_buff
*rxskb,
+ int reason)
{
int err;
const struct iphdr *rxiph;
@@ -706,7 +708,7 @@ int dccp_v4_do_rcv(struct sock *sk, struct sk_buff *skb)
return 0;
reset:
- dccp_v4_ctl_send_reset(sk, skb);
+ dccp_v4_ctl_send_reset(sk, skb, SK_RST_REASON_NOT_SPECIFIED);
kfree_skb(skb);
return 0;
}
@@ -869,7 +871,7 @@ static int dccp_v4_rcv(struct sk_buff *skb)
if (nsk == sk) {
reqsk_put(req);
} else if (dccp_child_process(sk, nsk, skb)) {
- dccp_v4_ctl_send_reset(sk, skb);
+ dccp_v4_ctl_send_reset(sk, skb,
SK_RST_REASON_NOT_SPECIFIED);
goto discard_and_relse;
} else {
sock_put(sk);
@@ -909,7 +911,7 @@ static int dccp_v4_rcv(struct sk_buff *skb)
if (dh->dccph_type != DCCP_PKT_RESET) {
DCCP_SKB_CB(skb)->dccpd_reset_code =
DCCP_RESET_CODE_NO_CONNECTION;
- dccp_v4_ctl_send_reset(sk, skb);
+ dccp_v4_ctl_send_reset(sk, skb, SK_RST_REASON_NOT_SPECIFIED);
}
discard_it:
diff --git a/net/dccp/ipv6.c b/net/dccp/ipv6.c
index c8ca703dc331..232092dc3887 100644
--- a/net/dccp/ipv6.c
+++ b/net/dccp/ipv6.c
@@ -29,6 +29,7 @@
#include
#include
#include
+#include
#include "dccp.h"
#include "ipv6.h"
@@ -256,7 +257,8 @@ static void dccp_v6_reqsk_destructor(struct request_sock
*req)
kfree_skb(inet_rsk(req)->pktopts);
}
-static void dccp_v6_ctl_send_reset(const struct sock *sk, struct sk_buff
*rxskb)
+static void dccp_v6_ctl_send_reset(const struct sock *sk, struct sk_buff
*rxskb,
+ int reason)
{
const struct ipv6hdr *rxip6h;
struct sk_buff *skb;
@@ -656,7 +658,7 @@ static int dccp_v6_do_rcv(struct sock *sk, struct sk_buff
*skb)
return 0;
reset:
- dccp_v6_ctl_send_reset(sk, skb);
+ dccp_v6_ctl_send_reset(sk, skb, SK_RST_REASON_NOT_SPECIFIED);
discard:
if (opt_skb != NULL)
__kfree_skb(opt_skb);
@@ -762,7 +764,7 @@ static int dccp_v6_rcv(struct sk_buff *skb)
if (nsk == sk) {
reqsk_put(req);
} else if (dccp_child_process(sk, nsk, skb)) {
- dccp_v6_ctl_send_reset(sk, skb);
+ dccp_v6_ctl_send_reset(sk, skb,
SK_RST_REASON_NOT_SPECIFIED);
goto discard_and_relse;
} else {
sock_put(sk);
@@ -801,7 +803,7 @@ static int dccp_v6_rcv(struct sk_buff *skb)
if (dh->dccph_type != DCCP_PKT_RESET) {
DCCP_SKB_CB(skb)->dccpd_reset_code =
DCCP_RESET_CODE_NO_CONNECTION;
- dccp_v6_ctl_send_reset(sk, skb);
+ dccp_v6_ctl_send_reset(sk, skb, SK_RST_REASON_NOT_SPECIFIED);
}
discard_it:
diff --git a/net/dccp/minisocks.c b/net/dccp/minisocks.c
index 64d805b27add..251a57cf5822 100644
--- a/net/dccp/minisocks.c
+++ b/net/dccp/minisocks.c
@@ -15,6 +15,7 @@
#include
[PATCH net-next v2 1/6] net: introduce rstreason to detect why the RST is sent
From: Jason Xing
Add a new standalone file for the easy future extension to support
both active reset and passive reset in the TCP/DCCP/MPTCP protocols.
This patch only does the preparations for reset reason mechanism,
nothing else changes.
The reset reasons are divided into three parts:
1) reuse drop reasons for passive reset in TCP
2) reuse MP_TCPRST option for MPTCP
3) our own reasons
I will implement the basic codes of active/passive reset reason in
those three protocols, which is not complete for this moment. But
it provides a new chance to let other people add more reasons into
it:)
Signed-off-by: Jason Xing
---
include/net/rstreason.h | 93 +
1 file changed, 93 insertions(+)
create mode 100644 include/net/rstreason.h
diff --git a/include/net/rstreason.h b/include/net/rstreason.h
new file mode 100644
index ..24d098a78a60
--- /dev/null
+++ b/include/net/rstreason.h
@@ -0,0 +1,93 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+
+#ifndef _LINUX_RSTREASON_H
+#define _LINUX_RSTREASON_H
+#include
+
+#define DEFINE_RST_REASON(FN, FNe) \
+ FN(MPTCP_RST_EUNSPEC) \
+ FN(MPTCP_RST_EMPTCP)\
+ FN(MPTCP_RST_ERESOURCE) \
+ FN(MPTCP_RST_EPROHIBIT) \
+ FN(MPTCP_RST_EWQ2BIG) \
+ FN(MPTCP_RST_EBADPERF) \
+ FN(MPTCP_RST_EMIDDLEBOX)\
+ FN(NOT_SPECIFIED) \
+ FNe(MAX)
+
+#define RST_REASON_START (SKB_DROP_REASON_MAX + 1)
+
+/* There are three parts in order:
+ * 1) 0 - SKB_DROP_REASON_MAX: rely on drop reasons for passive reset in TCP
+ * 2) SKB_DROP_REASON_MAX + 1 - MPTCP_RST_EMIDDLEBOX: for MPTCP use
+ * 3) MPTCP_RST_EMIDDLEBOX - SK_RST_REASON_MAX: independent reset reason
+ */
+enum sk_rst_reason {
+ /* Leave this 'blank' part (0-SKB_DROP_REASON_MAX) for the reuse
+* of skb drop reason because rst reason relies on what drop reason
+* indicates exactly why it could happen.
+*/
+
+ /* Copy from include/uapi/linux/mptcp.h.
+* These reset fields will not be changed since they adhere to
+* RFC 8684. So do not touch them. I'm going to list each definition
+* of them respectively.
+*/
+ /* Unspecified error.
+* This is the default error; it implies that the subflow is no
+* longer available. The presence of this option shows that the
+* RST was generated by an MPTCP-aware device.
+*/
+ SK_RST_REASON_MPTCP_RST_EUNSPEC = RST_REASON_START,
+ /* MPTCP-specific error.
+* An error has been detected in the processing of MPTCP options.
+* This is the usual reason code to return in the cases where a RST
+* is being sent to close a subflow because of an invalid response.
+*/
+ SK_RST_REASON_MPTCP_RST_EMPTCP,
+ /* Lack of resources.
+* This code indicates that the sending host does not have enough
+* resources to support the terminated subflow.
+*/
+ SK_RST_REASON_MPTCP_RST_ERESOURCE,
+ /* Administratively prohibited.
+* This code indicates that the requested subflow is prohibited by
+* the policies of the sending host.
+*/
+ SK_RST_REASON_MPTCP_RST_EPROHIBIT,
+ /* Too much outstanding data.
+* This code indicates that there is an excessive amount of data
+* that needs to be transmitted over the terminated subflow while
+* having already been acknowledged over one or more other subflows.
+* This may occur if a path has been unavailable for a short period
+* and it is more efficient to reset and start again than it is to
+* retransmit the queued data.
+*/
+ SK_RST_REASON_MPTCP_RST_EWQ2BIG,
+ /* Unacceptable performance.
+* This code indicates that the performance of this subflow was
+* too low compared to the other subflows of this Multipath TCP
+* connection.
+*/
+ SK_RST_REASON_MPTCP_RST_EBADPERF,
+ /* Middlebox interference.
+* Middlebox interference has been detected over this subflow,
+* making MPTCP signaling invalid. For example, this may be sent
+* if the checksum does not validate.
+*/
+ SK_RST_REASON_MPTCP_RST_EMIDDLEBOX,
+
+ /* For the real standalone socket reset reason, we start from here */
+ SK_RST_REASON_NOT_SPECIFIED,
+
+ /* Maximum of socket reset reasons.
+* It shouldn't be used as a real 'reason'.
+*/
+ SK_RST_REASON_MAX,
+};
+
+static inline int convert_mptcp_reason(int reason)
+{
+ return reason += RST_REASON_START;
+}
+#endif
--
2.37.3
[PATCH net-next 0/6] Implement reset reason mechanism to detect
From: Jason Xing In production, there are so many cases about why the RST skb is sent but we don't have a very convenient/fast method to detect the exact underlying reasons. RST is implemented in two kinds: passive kind (like tcp_v4_send_reset()) and active kind (like tcp_send_active_reset()). The former can be traced carefully 1) in TCP, with the help of drop reasons, which is based on Eric's idea[1], 2) in MPTCP, with the help of reset options defined in RFC 8684. The latter is relatively independent, which should be implemented on our own. In this series, I focus on the fundamental implement mostly about how the rstreason mechnism and the detailed passive part works as an example, not including the active reset part. In future, we can go further and refine those NOT_SPECIFIED reasons. Here are some examples when tracing: -0 [002] ..s1. 1830.262425: tcp_send_reset: skbaddr=x skaddr=x src=x dest=x state=x reason=NOT_SPECIFIED -0 [002] ..s1. 1830.262425: tcp_send_reset: skbaddr=x skaddr=x src=x dest=x state=x reason=NO_SOCKET [1] Link: https://lore.kernel.org/all/CANn89iJw8x-LqgsWOeJQQvgVg6DnL5aBRLi10QN2WBdr+X4k=w...@mail.gmail.com/ v2 Link: https://lore.kernel.org/all/20240403185033.47ebc...@kernel.org/ 1. rebase against the latest net-next tree Jason Xing (6): net: introduce rstreason to detect why the RST is sent rstreason: prepare for passive reset rstreason: prepare for active reset tcp: support rstreason for passive reset mptcp: support rstreason for passive reset rstreason: make it work in trace world include/net/request_sock.h | 3 +- include/net/rstreason.h| 93 ++ include/net/tcp.h | 2 +- include/trace/events/tcp.h | 37 +-- net/dccp/ipv4.c| 10 ++-- net/dccp/ipv6.c| 10 ++-- net/dccp/minisocks.c | 3 +- net/ipv4/tcp.c | 15 -- net/ipv4/tcp_ipv4.c| 14 +++--- net/ipv4/tcp_minisocks.c | 3 +- net/ipv4/tcp_output.c | 4 +- net/ipv4/tcp_timer.c | 9 ++-- net/ipv6/tcp_ipv6.c| 17 --- net/mptcp/protocol.c | 4 +- net/mptcp/subflow.c| 33 ++ 15 files changed, 209 insertions(+), 48 deletions(-) create mode 100644 include/net/rstreason.h -- 2.37.3
