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* [PATCH net-next 0/8] mptcp: small improvements, fix and clean-ups
@ 2024-05-10 11:18 Matthieu Baerts (NGI0)
  2024-05-10 11:18 ` [PATCH net-next 1/8] mptcp: SO_KEEPALIVE: fix getsockopt support Matthieu Baerts (NGI0)
                   ` (8 more replies)
  0 siblings, 9 replies; 14+ messages in thread
From: Matthieu Baerts (NGI0) @ 2024-05-10 11:18 UTC (permalink / raw
  To: mptcp, Mat Martineau, Geliang Tang, David S. Miller, Eric Dumazet,
	Jakub Kicinski, Paolo Abeni, Florian Westphal
  Cc: netdev, linux-kernel, Matthieu Baerts (NGI0), Gregory Detal

This series contain mostly unrelated patches:

- The two first patches can be seen as "fixes". They are part of this
  series for -next because it looks like the last batch of fixes for
  v6.9 has already been sent. These fixes are not urgent, so they can
  wait if an unlikely v6.9-rc8 is published. About the two patches:
    - Patch 1 fixes getsockopt(SO_KEEPALIVE) support on MPTCP sockets
    - Patch 2 makes sure the full TCP keep-alive feature is supported,
      not just SO_KEEPALIVE.

- Patch 3 is a small optimisation when getsockopt(MPTCP_INFO) is used
  without buffer, just to check if MPTCP is still being used: no
  fallback to TCP.

- Patch 4 adds net.mptcp.available_schedulers sysctl knob to list packet
  schedulers, similar to net.ipv4.tcp_available_congestion_control.

- Patch 5 and 6 fix CheckPatch warnings: "prefer strscpy over strcpy"
  and "else is not generally useful after a break or return".

- Patch 7 and 8 remove and add header includes to avoid unused ones, and
  add missing ones to be self-contained.

Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
---
Gregory Detal (1):
      mptcp: add net.mptcp.available_schedulers

Matthieu Baerts (NGI0) (7):
      mptcp: SO_KEEPALIVE: fix getsockopt support
      mptcp: fix full TCP keep-alive support
      mptcp: sockopt: info: stop early if no buffer
      mptcp: prefer strscpy over strcpy
      mptcp: remove unnecessary else statements
      mptcp: move mptcp_pm_gen.h's include
      mptcp: include inet_common in mib.h

 include/net/mptcp.h      |  3 +++
 net/mptcp/ctrl.c         | 29 +++++++++++++++++++--
 net/mptcp/mib.h          |  2 ++
 net/mptcp/pm_netlink.c   |  1 +
 net/mptcp/pm_userspace.c |  1 +
 net/mptcp/protocol.c     |  5 ++--
 net/mptcp/protocol.h     |  6 +++--
 net/mptcp/sched.c        | 22 ++++++++++++++++
 net/mptcp/sockopt.c      | 66 +++++++++++++++++++++++++++++++++++++++++++++---
 net/mptcp/subflow.c      | 32 ++++++++++++-----------
 10 files changed, 143 insertions(+), 24 deletions(-)
---
base-commit: 383eed2de529287337d9153a5084d4291a7c69f2
change-id: 20240509-upstream-net-next-20240509-misc-improvements-84b3489136f3

Best regards,
-- 
Matthieu Baerts (NGI0) <matttbe@kernel.org>


^ permalink raw reply	[flat|nested] 14+ messages in thread

* [PATCH net-next 1/8] mptcp: SO_KEEPALIVE: fix getsockopt support
  2024-05-10 11:18 [PATCH net-next 0/8] mptcp: small improvements, fix and clean-ups Matthieu Baerts (NGI0)
@ 2024-05-10 11:18 ` Matthieu Baerts (NGI0)
  2024-05-10 11:18 ` [PATCH net-next 2/8] mptcp: fix full TCP keep-alive support Matthieu Baerts (NGI0)
                   ` (7 subsequent siblings)
  8 siblings, 0 replies; 14+ messages in thread
From: Matthieu Baerts (NGI0) @ 2024-05-10 11:18 UTC (permalink / raw
  To: mptcp, Mat Martineau, Geliang Tang, David S. Miller, Eric Dumazet,
	Jakub Kicinski, Paolo Abeni, Florian Westphal
  Cc: netdev, linux-kernel, Matthieu Baerts (NGI0)

SO_KEEPALIVE support has to be set on each subflow: on each TCP socket,
where sk_prot->keepalive is defined. Technically, nothing has to be done
on the MPTCP socket. That's why mptcp_sol_socket_sync_intval() was
called instead of mptcp_sol_socket_intval().

Except that when nothing is done on the MPTCP socket, the
getsockopt(SO_KEEPALIVE), handled in net/core/sock.c:sk_getsockopt(),
will not know if SO_KEEPALIVE has been set on the different subflows or
not.

The fix is simple: simply call mptcp_sol_socket_intval() which will end
up calling net/core/sock.c:sk_setsockopt() where the SOCK_KEEPOPEN flag
will be set, the one used in sk_getsockopt().

So now, getsockopt(SO_KEEPALIVE) on an MPTCP socket will return the same
value as the one previously set with setsockopt(SO_KEEPALIVE).

Fixes: 1b3e7ede1365 ("mptcp: setsockopt: handle SO_KEEPALIVE and SO_PRIORITY")
Acked-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
---
 net/mptcp/sockopt.c | 2 --
 1 file changed, 2 deletions(-)

diff --git a/net/mptcp/sockopt.c b/net/mptcp/sockopt.c
index 1fea43f5b6f3..69fc584fc57e 100644
--- a/net/mptcp/sockopt.c
+++ b/net/mptcp/sockopt.c
@@ -181,8 +181,6 @@ static int mptcp_setsockopt_sol_socket_int(struct mptcp_sock *msk, int optname,
 
 	switch (optname) {
 	case SO_KEEPALIVE:
-		mptcp_sol_socket_sync_intval(msk, optname, val);
-		return 0;
 	case SO_DEBUG:
 	case SO_MARK:
 	case SO_PRIORITY:

-- 
2.43.0


^ permalink raw reply related	[flat|nested] 14+ messages in thread

* [PATCH net-next 2/8] mptcp: fix full TCP keep-alive support
  2024-05-10 11:18 [PATCH net-next 0/8] mptcp: small improvements, fix and clean-ups Matthieu Baerts (NGI0)
  2024-05-10 11:18 ` [PATCH net-next 1/8] mptcp: SO_KEEPALIVE: fix getsockopt support Matthieu Baerts (NGI0)
@ 2024-05-10 11:18 ` Matthieu Baerts (NGI0)
  2024-05-10 11:18 ` [PATCH net-next 3/8] mptcp: sockopt: info: stop early if no buffer Matthieu Baerts (NGI0)
                   ` (6 subsequent siblings)
  8 siblings, 0 replies; 14+ messages in thread
From: Matthieu Baerts (NGI0) @ 2024-05-10 11:18 UTC (permalink / raw
  To: mptcp, Mat Martineau, Geliang Tang, David S. Miller, Eric Dumazet,
	Jakub Kicinski, Paolo Abeni, Florian Westphal
  Cc: netdev, linux-kernel, Matthieu Baerts (NGI0)

SO_KEEPALIVE support has been added a while ago, as part of a series
"adding SOL_SOCKET" support. To have a full control of this keep-alive
feature, it is important to also support TCP_KEEP* socket options at the
SOL_TCP level.

Supporting them on the setsockopt() part is easy, it is just a matter of
remembering each value in the MPTCP sock structure, and calling
tcp_sock_set_keep*() helpers on each subflow. If the value is not
modified (0), calling these helpers will not do anything. For the
getsockopt() part, the corresponding value from the MPTCP sock structure
or the default one is simply returned. All of this is very similar to
other TCP_* socket options supported by MPTCP.

It looks important for kernels supporting SO_KEEPALIVE, to also support
TCP_KEEP* options as well: some apps seem to (wrongly) consider that if
the former is supported, the latter ones will be supported as well. But
also, not having this simple and isolated change is preventing MPTCP
support in some apps, and libraries like GoLang [1]. This is why this
patch is seen as a fix.

Closes: https://github.com/multipath-tcp/mptcp_net-next/issues/383
Fixes: 1b3e7ede1365 ("mptcp: setsockopt: handle SO_KEEPALIVE and SO_PRIORITY")
Link: https://github.com/golang/go/issues/56539 [1]
Acked-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
---
 net/mptcp/protocol.h |  3 +++
 net/mptcp/sockopt.c  | 58 ++++++++++++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 61 insertions(+)

diff --git a/net/mptcp/protocol.h b/net/mptcp/protocol.h
index cfc5f9c3f113..4dcce3641d1d 100644
--- a/net/mptcp/protocol.h
+++ b/net/mptcp/protocol.h
@@ -312,6 +312,9 @@ struct mptcp_sock {
 			free_first:1,
 			rcvspace_init:1;
 	u32		notsent_lowat;
+	int		keepalive_cnt;
+	int		keepalive_idle;
+	int		keepalive_intvl;
 	struct work_struct work;
 	struct sk_buff  *ooo_last_skb;
 	struct rb_root  out_of_order_queue;
diff --git a/net/mptcp/sockopt.c b/net/mptcp/sockopt.c
index 69fc584fc57e..63a3edc75857 100644
--- a/net/mptcp/sockopt.c
+++ b/net/mptcp/sockopt.c
@@ -622,6 +622,31 @@ static int mptcp_setsockopt_sol_tcp_congestion(struct mptcp_sock *msk, sockptr_t
 	return ret;
 }
 
+static int __mptcp_setsockopt_set_val(struct mptcp_sock *msk, int max,
+				      int (*set_val)(struct sock *, int),
+				      int *msk_val, int val)
+{
+	struct mptcp_subflow_context *subflow;
+	int err = 0;
+
+	mptcp_for_each_subflow(msk, subflow) {
+		struct sock *ssk = mptcp_subflow_tcp_sock(subflow);
+		int ret;
+
+		lock_sock(ssk);
+		ret = set_val(ssk, val);
+		err = err ? : ret;
+		release_sock(ssk);
+	}
+
+	if (!err) {
+		*msk_val = val;
+		sockopt_seq_inc(msk);
+	}
+
+	return err;
+}
+
 static int __mptcp_setsockopt_sol_tcp_cork(struct mptcp_sock *msk, int val)
 {
 	struct mptcp_subflow_context *subflow;
@@ -818,6 +843,22 @@ static int mptcp_setsockopt_sol_tcp(struct mptcp_sock *msk, int optname,
 	case TCP_NODELAY:
 		ret = __mptcp_setsockopt_sol_tcp_nodelay(msk, val);
 		break;
+	case TCP_KEEPIDLE:
+		ret = __mptcp_setsockopt_set_val(msk, MAX_TCP_KEEPIDLE,
+						 &tcp_sock_set_keepidle_locked,
+						 &msk->keepalive_idle, val);
+		break;
+	case TCP_KEEPINTVL:
+		ret = __mptcp_setsockopt_set_val(msk, MAX_TCP_KEEPINTVL,
+						 &tcp_sock_set_keepintvl,
+						 &msk->keepalive_intvl, val);
+		break;
+	case TCP_KEEPCNT:
+		ret = __mptcp_setsockopt_set_val(msk, MAX_TCP_KEEPCNT,
+						 &tcp_sock_set_keepcnt,
+						 &msk->keepalive_cnt,
+						 val);
+		break;
 	default:
 		ret = -ENOPROTOOPT;
 	}
@@ -1326,6 +1367,8 @@ static int mptcp_put_int_option(struct mptcp_sock *msk, char __user *optval,
 static int mptcp_getsockopt_sol_tcp(struct mptcp_sock *msk, int optname,
 				    char __user *optval, int __user *optlen)
 {
+	struct sock *sk = (void *)msk;
+
 	switch (optname) {
 	case TCP_ULP:
 	case TCP_CONGESTION:
@@ -1344,6 +1387,18 @@ static int mptcp_getsockopt_sol_tcp(struct mptcp_sock *msk, int optname,
 		return mptcp_put_int_option(msk, optval, optlen, msk->cork);
 	case TCP_NODELAY:
 		return mptcp_put_int_option(msk, optval, optlen, msk->nodelay);
+	case TCP_KEEPIDLE:
+		return mptcp_put_int_option(msk, optval, optlen,
+					    msk->keepalive_idle ? :
+					    READ_ONCE(sock_net(sk)->ipv4.sysctl_tcp_keepalive_time) / HZ);
+	case TCP_KEEPINTVL:
+		return mptcp_put_int_option(msk, optval, optlen,
+					    msk->keepalive_intvl ? :
+					    READ_ONCE(sock_net(sk)->ipv4.sysctl_tcp_keepalive_intvl) / HZ);
+	case TCP_KEEPCNT:
+		return mptcp_put_int_option(msk, optval, optlen,
+					    msk->keepalive_cnt ? :
+					    READ_ONCE(sock_net(sk)->ipv4.sysctl_tcp_keepalive_probes));
 	case TCP_NOTSENT_LOWAT:
 		return mptcp_put_int_option(msk, optval, optlen, msk->notsent_lowat);
 	}
@@ -1461,6 +1516,9 @@ static void sync_socket_options(struct mptcp_sock *msk, struct sock *ssk)
 		tcp_set_congestion_control(ssk, msk->ca_name, false, true);
 	__tcp_sock_set_cork(ssk, !!msk->cork);
 	__tcp_sock_set_nodelay(ssk, !!msk->nodelay);
+	tcp_sock_set_keepidle_locked(ssk, msk->keepalive_idle);
+	tcp_sock_set_keepintvl(ssk, msk->keepalive_intvl);
+	tcp_sock_set_keepcnt(ssk, msk->keepalive_cnt);
 
 	inet_assign_bit(TRANSPARENT, ssk, inet_test_bit(TRANSPARENT, sk));
 	inet_assign_bit(FREEBIND, ssk, inet_test_bit(FREEBIND, sk));

-- 
2.43.0


^ permalink raw reply related	[flat|nested] 14+ messages in thread

* [PATCH net-next 3/8] mptcp: sockopt: info: stop early if no buffer
  2024-05-10 11:18 [PATCH net-next 0/8] mptcp: small improvements, fix and clean-ups Matthieu Baerts (NGI0)
  2024-05-10 11:18 ` [PATCH net-next 1/8] mptcp: SO_KEEPALIVE: fix getsockopt support Matthieu Baerts (NGI0)
  2024-05-10 11:18 ` [PATCH net-next 2/8] mptcp: fix full TCP keep-alive support Matthieu Baerts (NGI0)
@ 2024-05-10 11:18 ` Matthieu Baerts (NGI0)
  2024-05-10 11:18 ` [PATCH net-next 4/8] mptcp: add net.mptcp.available_schedulers Matthieu Baerts (NGI0)
                   ` (5 subsequent siblings)
  8 siblings, 0 replies; 14+ messages in thread
From: Matthieu Baerts (NGI0) @ 2024-05-10 11:18 UTC (permalink / raw
  To: mptcp, Mat Martineau, Geliang Tang, David S. Miller, Eric Dumazet,
	Jakub Kicinski, Paolo Abeni, Florian Westphal
  Cc: netdev, linux-kernel, Matthieu Baerts (NGI0)

Up to recently, it has been recommended to use getsockopt(MPTCP_INFO) to
check if a fallback to TCP happened, or if the client requested to use
MPTCP.

In this case, the userspace app is only interested by the returned value
of the getsocktop() call, and can then give 0 for the option length, and
NULL for the buffer address. An easy optimisation is then to stop early,
and avoid filling a local buffer -- which now requires two different
locks -- if it is not needed.

Reviewed-by: Mat Martineau <martineau@kernel.org>
Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
---
 net/mptcp/sockopt.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/net/mptcp/sockopt.c b/net/mptcp/sockopt.c
index 63a3edc75857..cc9ecccf219d 100644
--- a/net/mptcp/sockopt.c
+++ b/net/mptcp/sockopt.c
@@ -999,6 +999,10 @@ static int mptcp_getsockopt_info(struct mptcp_sock *msk, char __user *optval, in
 	if (get_user(len, optlen))
 		return -EFAULT;
 
+	/* When used only to check if a fallback to TCP happened. */
+	if (len == 0)
+		return 0;
+
 	len = min_t(unsigned int, len, sizeof(struct mptcp_info));
 
 	mptcp_diag_fill_info(msk, &m_info);

-- 
2.43.0


^ permalink raw reply related	[flat|nested] 14+ messages in thread

* [PATCH net-next 4/8] mptcp: add net.mptcp.available_schedulers
  2024-05-10 11:18 [PATCH net-next 0/8] mptcp: small improvements, fix and clean-ups Matthieu Baerts (NGI0)
                   ` (2 preceding siblings ...)
  2024-05-10 11:18 ` [PATCH net-next 3/8] mptcp: sockopt: info: stop early if no buffer Matthieu Baerts (NGI0)
@ 2024-05-10 11:18 ` Matthieu Baerts (NGI0)
  2024-05-10 11:18 ` [PATCH net-next 5/8] mptcp: prefer strscpy over strcpy Matthieu Baerts (NGI0)
                   ` (4 subsequent siblings)
  8 siblings, 0 replies; 14+ messages in thread
From: Matthieu Baerts (NGI0) @ 2024-05-10 11:18 UTC (permalink / raw
  To: mptcp, Mat Martineau, Geliang Tang, David S. Miller, Eric Dumazet,
	Jakub Kicinski, Paolo Abeni, Florian Westphal
  Cc: netdev, linux-kernel, Matthieu Baerts (NGI0), Gregory Detal

From: Gregory Detal <gregory.detal@gmail.com>

The sysctl lists the available schedulers that can be set using
net.mptcp.scheduler similarly to net.ipv4.tcp_available_congestion_control.

Signed-off-by: Gregory Detal <gregory.detal@gmail.com>
Reviewed-by: Mat Martineau <martineau@kernel.org>
Tested-by: Geliang Tang <geliang@kernel.org>
Reviewed-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
---
 include/net/mptcp.h  |  3 +++
 net/mptcp/ctrl.c     | 27 ++++++++++++++++++++++++++-
 net/mptcp/protocol.h |  1 +
 net/mptcp/sched.c    | 22 ++++++++++++++++++++++
 4 files changed, 52 insertions(+), 1 deletion(-)

diff --git a/include/net/mptcp.h b/include/net/mptcp.h
index fb996124b3d5..0bc4ab03f487 100644
--- a/include/net/mptcp.h
+++ b/include/net/mptcp.h
@@ -97,6 +97,9 @@ struct mptcp_out_options {
 };
 
 #define MPTCP_SCHED_NAME_MAX	16
+#define MPTCP_SCHED_MAX		128
+#define MPTCP_SCHED_BUF_MAX	(MPTCP_SCHED_NAME_MAX * MPTCP_SCHED_MAX)
+
 #define MPTCP_SUBFLOWS_MAX	8
 
 struct mptcp_sched_data {
diff --git a/net/mptcp/ctrl.c b/net/mptcp/ctrl.c
index 49abf80b3fad..542555ba474c 100644
--- a/net/mptcp/ctrl.c
+++ b/net/mptcp/ctrl.c
@@ -133,6 +133,24 @@ static int proc_scheduler(struct ctl_table *ctl, int write,
 	return ret;
 }
 
+static int proc_available_schedulers(struct ctl_table *ctl,
+				     int write, void *buffer,
+				     size_t *lenp, loff_t *ppos)
+{
+	struct ctl_table tbl = { .maxlen = MPTCP_SCHED_BUF_MAX, };
+	int ret;
+
+	tbl.data = kmalloc(tbl.maxlen, GFP_USER);
+	if (!tbl.data)
+		return -ENOMEM;
+
+	mptcp_get_available_schedulers(tbl.data, MPTCP_SCHED_BUF_MAX);
+	ret = proc_dostring(&tbl, write, buffer, lenp, ppos);
+	kfree(tbl.data);
+
+	return ret;
+}
+
 static struct ctl_table mptcp_sysctl_table[] = {
 	{
 		.procname = "enabled",
@@ -187,6 +205,12 @@ static struct ctl_table mptcp_sysctl_table[] = {
 		.mode = 0644,
 		.proc_handler = proc_scheduler,
 	},
+	{
+		.procname = "available_schedulers",
+		.maxlen	= MPTCP_SCHED_BUF_MAX,
+		.mode = 0644,
+		.proc_handler = proc_available_schedulers,
+	},
 	{
 		.procname = "close_timeout",
 		.maxlen = sizeof(unsigned int),
@@ -214,7 +238,8 @@ static int mptcp_pernet_new_table(struct net *net, struct mptcp_pernet *pernet)
 	table[4].data = &pernet->stale_loss_cnt;
 	table[5].data = &pernet->pm_type;
 	table[6].data = &pernet->scheduler;
-	table[7].data = &pernet->close_timeout;
+	/* table[7] is for available_schedulers which is read-only info */
+	table[8].data = &pernet->close_timeout;
 
 	hdr = register_net_sysctl_sz(net, MPTCP_SYSCTL_PATH, table,
 				     ARRAY_SIZE(mptcp_sysctl_table));
diff --git a/net/mptcp/protocol.h b/net/mptcp/protocol.h
index 4dcce3641d1d..39fc47e6b88a 100644
--- a/net/mptcp/protocol.h
+++ b/net/mptcp/protocol.h
@@ -686,6 +686,7 @@ unsigned int mptcp_stale_loss_cnt(const struct net *net);
 unsigned int mptcp_close_timeout(const struct sock *sk);
 int mptcp_get_pm_type(const struct net *net);
 const char *mptcp_get_scheduler(const struct net *net);
+void mptcp_get_available_schedulers(char *buf, size_t maxlen);
 void __mptcp_subflow_fully_established(struct mptcp_sock *msk,
 				       struct mptcp_subflow_context *subflow,
 				       const struct mptcp_options_received *mp_opt);
diff --git a/net/mptcp/sched.c b/net/mptcp/sched.c
index 4ab0693c069c..4a7fd0508ad2 100644
--- a/net/mptcp/sched.c
+++ b/net/mptcp/sched.c
@@ -51,6 +51,28 @@ struct mptcp_sched_ops *mptcp_sched_find(const char *name)
 	return ret;
 }
 
+/* Build string with list of available scheduler values.
+ * Similar to tcp_get_available_congestion_control()
+ */
+void mptcp_get_available_schedulers(char *buf, size_t maxlen)
+{
+	struct mptcp_sched_ops *sched;
+	size_t offs = 0;
+
+	rcu_read_lock();
+	spin_lock(&mptcp_sched_list_lock);
+	list_for_each_entry_rcu(sched, &mptcp_sched_list, list) {
+		offs += snprintf(buf + offs, maxlen - offs,
+				 "%s%s",
+				 offs == 0 ? "" : " ", sched->name);
+
+		if (WARN_ON_ONCE(offs >= maxlen))
+			break;
+	}
+	spin_unlock(&mptcp_sched_list_lock);
+	rcu_read_unlock();
+}
+
 int mptcp_register_scheduler(struct mptcp_sched_ops *sched)
 {
 	if (!sched->get_subflow)

-- 
2.43.0


^ permalink raw reply related	[flat|nested] 14+ messages in thread

* [PATCH net-next 5/8] mptcp: prefer strscpy over strcpy
  2024-05-10 11:18 [PATCH net-next 0/8] mptcp: small improvements, fix and clean-ups Matthieu Baerts (NGI0)
                   ` (3 preceding siblings ...)
  2024-05-10 11:18 ` [PATCH net-next 4/8] mptcp: add net.mptcp.available_schedulers Matthieu Baerts (NGI0)
@ 2024-05-10 11:18 ` Matthieu Baerts (NGI0)
  2024-05-10 11:18 ` [PATCH net-next 6/8] mptcp: remove unnecessary else statements Matthieu Baerts (NGI0)
                   ` (3 subsequent siblings)
  8 siblings, 0 replies; 14+ messages in thread
From: Matthieu Baerts (NGI0) @ 2024-05-10 11:18 UTC (permalink / raw
  To: mptcp, Mat Martineau, Geliang Tang, David S. Miller, Eric Dumazet,
	Jakub Kicinski, Paolo Abeni, Florian Westphal
  Cc: netdev, linux-kernel, Matthieu Baerts (NGI0)

strcpy() performs no bounds checking on the destination buffer. This
could result in linear overflows beyond the end of the buffer, leading
to all kinds of misbehaviors. The safe replacement is strscpy() [1].

This is in preparation of a possible future step where all strcpy() uses
will be removed in favour of strscpy() [2].

This fixes CheckPatch warnings:

  WARNING: Prefer strscpy over strcpy

Link: https://www.kernel.org/doc/html/latest/process/deprecated.html#strcpy [1]
Link: https://github.com/KSPP/linux/issues/88 [2]
Reviewed-by: Geliang Tang <geliang@kernel.org>
Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
---
 net/mptcp/ctrl.c     | 2 +-
 net/mptcp/protocol.c | 5 +++--
 net/mptcp/sockopt.c  | 2 +-
 3 files changed, 5 insertions(+), 4 deletions(-)

diff --git a/net/mptcp/ctrl.c b/net/mptcp/ctrl.c
index 542555ba474c..98b1dd498ff6 100644
--- a/net/mptcp/ctrl.c
+++ b/net/mptcp/ctrl.c
@@ -92,7 +92,7 @@ static void mptcp_pernet_set_defaults(struct mptcp_pernet *pernet)
 	pernet->allow_join_initial_addr_port = 1;
 	pernet->stale_loss_cnt = 4;
 	pernet->pm_type = MPTCP_PM_TYPE_KERNEL;
-	strcpy(pernet->scheduler, "default");
+	strscpy(pernet->scheduler, "default", sizeof(pernet->scheduler));
 }
 
 #ifdef CONFIG_SYSCTL
diff --git a/net/mptcp/protocol.c b/net/mptcp/protocol.c
index bb8f96f2b86f..a42494d3a71b 100644
--- a/net/mptcp/protocol.c
+++ b/net/mptcp/protocol.c
@@ -2814,7 +2814,8 @@ static void mptcp_ca_reset(struct sock *sk)
 	struct inet_connection_sock *icsk = inet_csk(sk);
 
 	tcp_assign_congestion_control(sk);
-	strcpy(mptcp_sk(sk)->ca_name, icsk->icsk_ca_ops->name);
+	strscpy(mptcp_sk(sk)->ca_name, icsk->icsk_ca_ops->name,
+		sizeof(mptcp_sk(sk)->ca_name));
 
 	/* no need to keep a reference to the ops, the name will suffice */
 	tcp_cleanup_congestion_control(sk);
@@ -4169,7 +4170,7 @@ int __init mptcp_proto_v6_init(void)
 	int err;
 
 	mptcp_v6_prot = mptcp_prot;
-	strcpy(mptcp_v6_prot.name, "MPTCPv6");
+	strscpy(mptcp_v6_prot.name, "MPTCPv6", sizeof(mptcp_v6_prot.name));
 	mptcp_v6_prot.slab = NULL;
 	mptcp_v6_prot.obj_size = sizeof(struct mptcp6_sock);
 	mptcp_v6_prot.ipv6_pinfo_offset = offsetof(struct mptcp6_sock, np);
diff --git a/net/mptcp/sockopt.c b/net/mptcp/sockopt.c
index cc9ecccf219d..0f6ef494525f 100644
--- a/net/mptcp/sockopt.c
+++ b/net/mptcp/sockopt.c
@@ -616,7 +616,7 @@ static int mptcp_setsockopt_sol_tcp_congestion(struct mptcp_sock *msk, sockptr_t
 	}
 
 	if (ret == 0)
-		strcpy(msk->ca_name, name);
+		strscpy(msk->ca_name, name, sizeof(msk->ca_name));
 
 	release_sock(sk);
 	return ret;

-- 
2.43.0


^ permalink raw reply related	[flat|nested] 14+ messages in thread

* [PATCH net-next 6/8] mptcp: remove unnecessary else statements
  2024-05-10 11:18 [PATCH net-next 0/8] mptcp: small improvements, fix and clean-ups Matthieu Baerts (NGI0)
                   ` (4 preceding siblings ...)
  2024-05-10 11:18 ` [PATCH net-next 5/8] mptcp: prefer strscpy over strcpy Matthieu Baerts (NGI0)
@ 2024-05-10 11:18 ` Matthieu Baerts (NGI0)
  2024-05-10 11:18 ` [PATCH net-next 7/8] mptcp: move mptcp_pm_gen.h's include Matthieu Baerts (NGI0)
                   ` (2 subsequent siblings)
  8 siblings, 0 replies; 14+ messages in thread
From: Matthieu Baerts (NGI0) @ 2024-05-10 11:18 UTC (permalink / raw
  To: mptcp, Mat Martineau, Geliang Tang, David S. Miller, Eric Dumazet,
	Jakub Kicinski, Paolo Abeni, Florian Westphal
  Cc: netdev, linux-kernel, Matthieu Baerts (NGI0)

The 'else' statements are not needed here, because their previous 'if'
block ends with a 'return'.

This fixes CheckPatch warnings:

  WARNING: else is not generally useful after a break or return

Reviewed-by: Geliang Tang <geliang@kernel.org>
Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
---
 net/mptcp/subflow.c | 32 +++++++++++++++++---------------
 1 file changed, 17 insertions(+), 15 deletions(-)

diff --git a/net/mptcp/subflow.c b/net/mptcp/subflow.c
index c1d13e555d10..612c38570a64 100644
--- a/net/mptcp/subflow.c
+++ b/net/mptcp/subflow.c
@@ -1119,6 +1119,8 @@ static enum mapping_status get_mapping_status(struct sock *ssk,
 	}
 
 	if (mpext->data_fin == 1) {
+		u64 data_fin_seq;
+
 		if (data_len == 1) {
 			bool updated = mptcp_update_rcv_data_fin(msk, mpext->data_seq,
 								 mpext->dsn64);
@@ -1131,26 +1133,26 @@ static enum mapping_status get_mapping_status(struct sock *ssk,
 				 */
 				skb_ext_del(skb, SKB_EXT_MPTCP);
 				return MAPPING_OK;
-			} else {
-				if (updated)
-					mptcp_schedule_work((struct sock *)msk);
-
-				return MAPPING_DATA_FIN;
 			}
-		} else {
-			u64 data_fin_seq = mpext->data_seq + data_len - 1;
 
-			/* If mpext->data_seq is a 32-bit value, data_fin_seq
-			 * must also be limited to 32 bits.
-			 */
-			if (!mpext->dsn64)
-				data_fin_seq &= GENMASK_ULL(31, 0);
+			if (updated)
+				mptcp_schedule_work((struct sock *)msk);
 
-			mptcp_update_rcv_data_fin(msk, data_fin_seq, mpext->dsn64);
-			pr_debug("DATA_FIN with mapping seq=%llu dsn64=%d",
-				 data_fin_seq, mpext->dsn64);
+			return MAPPING_DATA_FIN;
 		}
 
+		data_fin_seq = mpext->data_seq + data_len - 1;
+
+		/* If mpext->data_seq is a 32-bit value, data_fin_seq must also
+		 * be limited to 32 bits.
+		 */
+		if (!mpext->dsn64)
+			data_fin_seq &= GENMASK_ULL(31, 0);
+
+		mptcp_update_rcv_data_fin(msk, data_fin_seq, mpext->dsn64);
+		pr_debug("DATA_FIN with mapping seq=%llu dsn64=%d",
+			 data_fin_seq, mpext->dsn64);
+
 		/* Adjust for DATA_FIN using 1 byte of sequence space */
 		data_len--;
 	}

-- 
2.43.0


^ permalink raw reply related	[flat|nested] 14+ messages in thread

* [PATCH net-next 7/8] mptcp: move mptcp_pm_gen.h's include
  2024-05-10 11:18 [PATCH net-next 0/8] mptcp: small improvements, fix and clean-ups Matthieu Baerts (NGI0)
                   ` (5 preceding siblings ...)
  2024-05-10 11:18 ` [PATCH net-next 6/8] mptcp: remove unnecessary else statements Matthieu Baerts (NGI0)
@ 2024-05-10 11:18 ` Matthieu Baerts (NGI0)
  2024-05-10 11:18 ` [PATCH net-next 8/8] mptcp: include inet_common in mib.h Matthieu Baerts (NGI0)
  2024-05-13 23:06 ` [PATCH net-next 0/8] mptcp: small improvements, fix and clean-ups Jakub Kicinski
  8 siblings, 0 replies; 14+ messages in thread
From: Matthieu Baerts (NGI0) @ 2024-05-10 11:18 UTC (permalink / raw
  To: mptcp, Mat Martineau, Geliang Tang, David S. Miller, Eric Dumazet,
	Jakub Kicinski, Paolo Abeni, Florian Westphal
  Cc: netdev, linux-kernel, Matthieu Baerts (NGI0)

Nothing from protocol.h depends on mptcp_pm_gen.h, only code from
pm_netlink.c and pm_userspace.c depends on it.

So this include can be moved where it is needed to avoid a "unused
includes" warning.

Reviewed-by: Geliang Tang <geliang@kernel.org>
Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
---
 net/mptcp/pm_netlink.c   | 1 +
 net/mptcp/pm_userspace.c | 1 +
 net/mptcp/protocol.h     | 2 --
 3 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/net/mptcp/pm_netlink.c b/net/mptcp/pm_netlink.c
index 5c17d39146ea..7f53e022e27e 100644
--- a/net/mptcp/pm_netlink.c
+++ b/net/mptcp/pm_netlink.c
@@ -14,6 +14,7 @@
 
 #include "protocol.h"
 #include "mib.h"
+#include "mptcp_pm_gen.h"
 
 static int pm_nl_pernet_id;
 
diff --git a/net/mptcp/pm_userspace.c b/net/mptcp/pm_userspace.c
index 9f5d422d5ef6..f0a4590506c6 100644
--- a/net/mptcp/pm_userspace.c
+++ b/net/mptcp/pm_userspace.c
@@ -6,6 +6,7 @@
 
 #include "protocol.h"
 #include "mib.h"
+#include "mptcp_pm_gen.h"
 
 void mptcp_free_local_addr_list(struct mptcp_sock *msk)
 {
diff --git a/net/mptcp/protocol.h b/net/mptcp/protocol.h
index 39fc47e6b88a..7aa47e2dd52b 100644
--- a/net/mptcp/protocol.h
+++ b/net/mptcp/protocol.h
@@ -14,8 +14,6 @@
 #include <net/genetlink.h>
 #include <net/rstreason.h>
 
-#include "mptcp_pm_gen.h"
-
 #define MPTCP_SUPPORTED_VERSION	1
 
 /* MPTCP option bits */

-- 
2.43.0


^ permalink raw reply related	[flat|nested] 14+ messages in thread

* [PATCH net-next 8/8] mptcp: include inet_common in mib.h
  2024-05-10 11:18 [PATCH net-next 0/8] mptcp: small improvements, fix and clean-ups Matthieu Baerts (NGI0)
                   ` (6 preceding siblings ...)
  2024-05-10 11:18 ` [PATCH net-next 7/8] mptcp: move mptcp_pm_gen.h's include Matthieu Baerts (NGI0)
@ 2024-05-10 11:18 ` Matthieu Baerts (NGI0)
  2024-05-13 23:06 ` [PATCH net-next 0/8] mptcp: small improvements, fix and clean-ups Jakub Kicinski
  8 siblings, 0 replies; 14+ messages in thread
From: Matthieu Baerts (NGI0) @ 2024-05-10 11:18 UTC (permalink / raw
  To: mptcp, Mat Martineau, Geliang Tang, David S. Miller, Eric Dumazet,
	Jakub Kicinski, Paolo Abeni, Florian Westphal
  Cc: netdev, linux-kernel, Matthieu Baerts (NGI0)

So this file is now self-contained: it can be compiled alone with
analytic tools.

Reviewed-by: Geliang Tang <geliang@kernel.org>
Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
---
 net/mptcp/mib.h | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/net/mptcp/mib.h b/net/mptcp/mib.h
index dd7fd1f246b5..2704afd0dfe4 100644
--- a/net/mptcp/mib.h
+++ b/net/mptcp/mib.h
@@ -1,5 +1,7 @@
 /* SPDX-License-Identifier: GPL-2.0-or-later */
 
+#include <net/inet_common.h>
+
 enum linux_mptcp_mib_field {
 	MPTCP_MIB_NUM = 0,
 	MPTCP_MIB_MPCAPABLEPASSIVE,	/* Received SYN with MP_CAPABLE */

-- 
2.43.0


^ permalink raw reply related	[flat|nested] 14+ messages in thread

* Re: [PATCH net-next 0/8] mptcp: small improvements, fix and clean-ups
  2024-05-10 11:18 [PATCH net-next 0/8] mptcp: small improvements, fix and clean-ups Matthieu Baerts (NGI0)
                   ` (7 preceding siblings ...)
  2024-05-10 11:18 ` [PATCH net-next 8/8] mptcp: include inet_common in mib.h Matthieu Baerts (NGI0)
@ 2024-05-13 23:06 ` Jakub Kicinski
  2024-05-14  0:24   ` Mat Martineau
  8 siblings, 1 reply; 14+ messages in thread
From: Jakub Kicinski @ 2024-05-13 23:06 UTC (permalink / raw
  To: Matthieu Baerts (NGI0)
  Cc: mptcp, Mat Martineau, Geliang Tang, David S. Miller, Eric Dumazet,
	Paolo Abeni, Florian Westphal, netdev, linux-kernel,
	Gregory Detal

On Fri, 10 May 2024 13:18:30 +0200 Matthieu Baerts (NGI0) wrote:
> This series contain mostly unrelated patches:
> 
> - The two first patches can be seen as "fixes". They are part of this
>   series for -next because it looks like the last batch of fixes for
>   v6.9 has already been sent. These fixes are not urgent, so they can
>   wait if an unlikely v6.9-rc8 is published. About the two patches:
>     - Patch 1 fixes getsockopt(SO_KEEPALIVE) support on MPTCP sockets
>     - Patch 2 makes sure the full TCP keep-alive feature is supported,
>       not just SO_KEEPALIVE.
> 
> - Patch 3 is a small optimisation when getsockopt(MPTCP_INFO) is used
>   without buffer, just to check if MPTCP is still being used: no
>   fallback to TCP.
> 
> - Patch 4 adds net.mptcp.available_schedulers sysctl knob to list packet
>   schedulers, similar to net.ipv4.tcp_available_congestion_control.
> 
> - Patch 5 and 6 fix CheckPatch warnings: "prefer strscpy over strcpy"
>   and "else is not generally useful after a break or return".
> 
> - Patch 7 and 8 remove and add header includes to avoid unused ones, and
>   add missing ones to be self-contained.

Seems to conflict with:
https://lore.kernel.org/all/20240509-upstream-net-next-20240509-mptcp-tcp_is_mptcp-v1-1-f846df999202@kernel.org/
-- 
pw-bot: cr

^ permalink raw reply	[flat|nested] 14+ messages in thread

* Re: [PATCH net-next 0/8] mptcp: small improvements, fix and clean-ups
  2024-05-13 23:06 ` [PATCH net-next 0/8] mptcp: small improvements, fix and clean-ups Jakub Kicinski
@ 2024-05-14  0:24   ` Mat Martineau
  2024-05-14  0:29     ` Jakub Kicinski
  0 siblings, 1 reply; 14+ messages in thread
From: Mat Martineau @ 2024-05-14  0:24 UTC (permalink / raw
  To: Jakub Kicinski
  Cc: Matthieu Baerts (NGI0), mptcp, Geliang Tang, David S. Miller,
	Eric Dumazet, Paolo Abeni, Florian Westphal, netdev, linux-kernel,
	Gregory Detal

On Mon, 13 May 2024, Jakub Kicinski wrote:

> On Fri, 10 May 2024 13:18:30 +0200 Matthieu Baerts (NGI0) wrote:
>> This series contain mostly unrelated patches:
>>
>> - The two first patches can be seen as "fixes". They are part of this
>>   series for -next because it looks like the last batch of fixes for
>>   v6.9 has already been sent. These fixes are not urgent, so they can
>>   wait if an unlikely v6.9-rc8 is published. About the two patches:
>>     - Patch 1 fixes getsockopt(SO_KEEPALIVE) support on MPTCP sockets
>>     - Patch 2 makes sure the full TCP keep-alive feature is supported,
>>       not just SO_KEEPALIVE.
>>
>> - Patch 3 is a small optimisation when getsockopt(MPTCP_INFO) is used
>>   without buffer, just to check if MPTCP is still being used: no
>>   fallback to TCP.
>>
>> - Patch 4 adds net.mptcp.available_schedulers sysctl knob to list packet
>>   schedulers, similar to net.ipv4.tcp_available_congestion_control.
>>
>> - Patch 5 and 6 fix CheckPatch warnings: "prefer strscpy over strcpy"
>>   and "else is not generally useful after a break or return".
>>
>> - Patch 7 and 8 remove and add header includes to avoid unused ones, and
>>   add missing ones to be self-contained.
>
> Seems to conflict with:
> https://lore.kernel.org/all/20240509-upstream-net-next-20240509-mptcp-tcp_is_mptcp-v1-1-f846df999202@kernel.org/

Hi Jakub -

The conflict here is purely in the diff context, patch 2 of this series 
and "tcp: socket option to check for MPTCP fallback to TCP" add cases to 
the same switch statement and have a couple of unmodified lines between 
their additions.

"git am -3" handles it cleanly in this case, if you have time and 
inclination for a second attempt. But I realize you're working through a 
backlog and net-next is now closed, so that time might not be available. 
We'll try again when net-next reopens if needed.


Thanks,
Mat

^ permalink raw reply	[flat|nested] 14+ messages in thread

* Re: [PATCH net-next 0/8] mptcp: small improvements, fix and clean-ups
  2024-05-14  0:24   ` Mat Martineau
@ 2024-05-14  0:29     ` Jakub Kicinski
  2024-05-14  0:33       ` Mat Martineau
  0 siblings, 1 reply; 14+ messages in thread
From: Jakub Kicinski @ 2024-05-14  0:29 UTC (permalink / raw
  To: Mat Martineau
  Cc: Matthieu Baerts (NGI0), mptcp, Geliang Tang, David S. Miller,
	Eric Dumazet, Paolo Abeni, Florian Westphal, netdev, linux-kernel,
	Gregory Detal

On Mon, 13 May 2024 17:24:08 -0700 (PDT) Mat Martineau wrote:
> The conflict here is purely in the diff context, patch 2 of this series 
> and "tcp: socket option to check for MPTCP fallback to TCP" add cases to 
> the same switch statement and have a couple of unmodified lines between 
> their additions.
> 
> "git am -3" handles it cleanly in this case, if you have time and 
> inclination for a second attempt. But I realize you're working through a 
> backlog and net-next is now closed, so that time might not be available. 
> We'll try again when net-next reopens if needed.

Your -3 must be more powerful somehow, or my scripts are broken because
it isn't enough on my end.

If you can do a quick resend there's still a chance. The patches look
quite simple.

^ permalink raw reply	[flat|nested] 14+ messages in thread

* Re: [PATCH net-next 0/8] mptcp: small improvements, fix and clean-ups
  2024-05-14  0:29     ` Jakub Kicinski
@ 2024-05-14  0:33       ` Mat Martineau
  2024-05-14  8:06         ` Matthieu Baerts
  0 siblings, 1 reply; 14+ messages in thread
From: Mat Martineau @ 2024-05-14  0:33 UTC (permalink / raw
  To: Jakub Kicinski
  Cc: Matthieu Baerts (NGI0), mptcp, Geliang Tang, David S. Miller,
	Eric Dumazet, Paolo Abeni, Florian Westphal, netdev, linux-kernel,
	Gregory Detal

On Mon, 13 May 2024, Jakub Kicinski wrote:

> On Mon, 13 May 2024 17:24:08 -0700 (PDT) Mat Martineau wrote:
>> The conflict here is purely in the diff context, patch 2 of this series
>> and "tcp: socket option to check for MPTCP fallback to TCP" add cases to
>> the same switch statement and have a couple of unmodified lines between
>> their additions.
>>
>> "git am -3" handles it cleanly in this case, if you have time and
>> inclination for a second attempt. But I realize you're working through a
>> backlog and net-next is now closed, so that time might not be available.
>> We'll try again when net-next reopens if needed.
>
> Your -3 must be more powerful somehow, or my scripts are broken because
> it isn't enough on my end.
>
> If you can do a quick resend there's still a chance. The patches look
> quite simple.


Thanks Jakub! Spinning a quick v2 right now.


- Mat

^ permalink raw reply	[flat|nested] 14+ messages in thread

* Re: [PATCH net-next 0/8] mptcp: small improvements, fix and clean-ups
  2024-05-14  0:33       ` Mat Martineau
@ 2024-05-14  8:06         ` Matthieu Baerts
  0 siblings, 0 replies; 14+ messages in thread
From: Matthieu Baerts @ 2024-05-14  8:06 UTC (permalink / raw
  To: Mat Martineau, Jakub Kicinski
  Cc: mptcp, Geliang Tang, David S. Miller, Eric Dumazet, Paolo Abeni,
	Florian Westphal, netdev, linux-kernel, Gregory Detal

Hi Mat, Jakub,

On 14/05/2024 02:33, Mat Martineau wrote:
> On Mon, 13 May 2024, Jakub Kicinski wrote:
> 
>> On Mon, 13 May 2024 17:24:08 -0700 (PDT) Mat Martineau wrote:
>>> The conflict here is purely in the diff context, patch 2 of this series
>>> and "tcp: socket option to check for MPTCP fallback to TCP" add cases to
>>> the same switch statement and have a couple of unmodified lines between
>>> their additions.
>>>
>>> "git am -3" handles it cleanly in this case, if you have time and
>>> inclination for a second attempt. But I realize you're working through a
>>> backlog and net-next is now closed, so that time might not be available.
>>> We'll try again when net-next reopens if needed.
>>
>> Your -3 must be more powerful somehow, or my scripts are broken because
>> it isn't enough on my end.
>>
>> If you can do a quick resend there's still a chance. The patches look
>> quite simple.
> 
> 
> Thanks Jakub! Spinning a quick v2 right now.

Thank you for having sent a v2, and for having applied them!

I'm sorry about the conflicts: I moved the code around on purpose to
avoid them, but it looks like it was not enough. Like Mat, I didn't have
these conflicts locally when I tested before sending the patches. I will
check if there is something I can do to have the same error as the one
you had, to prevent such issues next time.

Cheers,
Matt
-- 
Sponsored by the NGI0 Core fund.


^ permalink raw reply	[flat|nested] 14+ messages in thread

end of thread, other threads:[~2024-05-14  8:06 UTC | newest]

Thread overview: 14+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2024-05-10 11:18 [PATCH net-next 0/8] mptcp: small improvements, fix and clean-ups Matthieu Baerts (NGI0)
2024-05-10 11:18 ` [PATCH net-next 1/8] mptcp: SO_KEEPALIVE: fix getsockopt support Matthieu Baerts (NGI0)
2024-05-10 11:18 ` [PATCH net-next 2/8] mptcp: fix full TCP keep-alive support Matthieu Baerts (NGI0)
2024-05-10 11:18 ` [PATCH net-next 3/8] mptcp: sockopt: info: stop early if no buffer Matthieu Baerts (NGI0)
2024-05-10 11:18 ` [PATCH net-next 4/8] mptcp: add net.mptcp.available_schedulers Matthieu Baerts (NGI0)
2024-05-10 11:18 ` [PATCH net-next 5/8] mptcp: prefer strscpy over strcpy Matthieu Baerts (NGI0)
2024-05-10 11:18 ` [PATCH net-next 6/8] mptcp: remove unnecessary else statements Matthieu Baerts (NGI0)
2024-05-10 11:18 ` [PATCH net-next 7/8] mptcp: move mptcp_pm_gen.h's include Matthieu Baerts (NGI0)
2024-05-10 11:18 ` [PATCH net-next 8/8] mptcp: include inet_common in mib.h Matthieu Baerts (NGI0)
2024-05-13 23:06 ` [PATCH net-next 0/8] mptcp: small improvements, fix and clean-ups Jakub Kicinski
2024-05-14  0:24   ` Mat Martineau
2024-05-14  0:29     ` Jakub Kicinski
2024-05-14  0:33       ` Mat Martineau
2024-05-14  8:06         ` Matthieu Baerts

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