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FAILED: patch "[PATCH] mptcp: disable add_addr retransmission when timeout is 0" failed to apply to 6.12-stable tree

PATCH New [email protected] 2 participants 2 messages Aug 22, 2025 – Aug 23, 2025

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author maintainer
#0 lore raw

The patch below does not apply to the 6.12-stable tree.
If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to <[email protected]>.

To reproduce the conflict and resubmit, you may use the following commands:

git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-6.12.y
git checkout FETCH_HEAD
git cherry-pick -x f5ce0714623cffd00bf2a83e890d09c609b7f50a
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<[email protected]>' --in-reply-to '2025082241-oxidant-avoid-0017@gregkh' --subject-prefix 'PATCH 6.12.y' HEAD^..

Possible dependencies:

thanks,

greg k-h

------------------ original commit in Linus's tree ------------------

From f5ce0714623cffd00bf2a83e890d09c609b7f50a Mon Sep 17 00:00:00 2001
From: Geliang Tang <[email protected]>
Date: Fri, 15 Aug 2025 19:28:23 +0200
Subject: [PATCH] mptcp: disable add_addr retransmission when timeout is 0

When add_addr_timeout was set to 0, this caused the ADD_ADDR to be retransmitted immediately, which looks like a buggy behaviour. Instead, interpret 0 as "no retransmissions needed".

The documentation is updated to explicitly state that setting the timeout to 0 disables retransmission.

Fixes 93f323b9cccc ("mptcp: add a new sysctl add_addr_timeout")
Cc [email protected]
Suggested-by Matthieu Baerts <[email protected]>
Signed-off-by Geliang Tang <[email protected]>
Reviewed-by Matthieu Baerts (NGI0) <[email protected]>
Signed-off-by Matthieu Baerts (NGI0) <[email protected]>
Link https://patch.msgid.link/20250815-net-mptcp-misc-fixes-6-17-rc2-v1-5-521fe9957892@kernel.org open here
Signed-off-by Jakub Kicinski <[email protected]>
Documentation/networking/mptcp-sysctl.rst +2 -0
index 5bfab01eff5a..1683c139821e 100644
@@ -12,6 +12,8 @@ add_addr_timeout - INTEGER (seconds)
 	resent to an MPTCP peer that has not acknowledged a previous
 	ADD_ADDR message.
 
+	Do not retransmit if set to 0.
+
 	The default value matches TCP_RTO_MAX. This is a per-namespace
 	sysctl.
net/mptcp/pm.c +10 -3
index c5f6a53ce5f1..136a380602ca 100644
@@ -274,6 +274,7 @@ static void mptcp_pm_add_timer(struct timer_list *timer)
 							      add_timer);
 	struct mptcp_sock *msk = entry->sock;
 	struct sock *sk = (struct sock *)msk;
+	unsigned int timeout;
 
 	pr_debug("msk=%p\n", msk);
 

@@ -291,6 +292,10 @@ static void mptcp_pm_add_timer(struct timer_list *timer)
 		goto out;
 	}
 
+	timeout = mptcp_get_add_addr_timeout(sock_net(sk));
+	if (!timeout)
+		goto out;
+
 	spin_lock_bh(&msk->pm.lock);
 
 	if (!mptcp_pm_should_add_signal_addr(msk)) {

@@ -302,7 +307,7 @@ static void mptcp_pm_add_timer(struct timer_list *timer)
 
 	if (entry->retrans_times < ADD_ADDR_RETRANS_MAX)
 		sk_reset_timer(sk, timer,
-			       jiffies + mptcp_get_add_addr_timeout(sock_net(sk)));
+			       jiffies + timeout);
 
 	spin_unlock_bh(&msk->pm.lock);
 

@@ -344,6 +349,7 @@ bool mptcp_pm_alloc_anno_list(struct mptcp_sock *msk,
 	struct mptcp_pm_add_entry *add_entry = NULL;
 	struct sock *sk = (struct sock *)msk;
 	struct net *net = sock_net(sk);
+	unsigned int timeout;
 
 	lockdep_assert_held(&msk->pm.lock);
 

@@ -368,8 +374,9 @@ bool mptcp_pm_alloc_anno_list(struct mptcp_sock *msk,
 
 	timer_setup(&add_entry->add_timer, mptcp_pm_add_timer, 0);
 reset_timer:
-	sk_reset_timer(sk, &add_entry->add_timer,
-		       jiffies + mptcp_get_add_addr_timeout(net));
+	timeout = mptcp_get_add_addr_timeout(net);
+	if (timeout)
+		sk_reset_timer(sk, &add_entry->add_timer, jiffies + timeout);
 
 	return true;
 }
maintainer
#1 lore raw

PATCH 1/1 mptcp: disable add_addr retransmission when timeout is 0

From: Geliang Tang <[email protected]>

[ Upstream commit f5ce0714623cffd00bf2a83e890d09c609b7f50a ]

When add_addr_timeout was set to 0, this caused the ADD_ADDR to be retransmitted immediately, which looks like a buggy behaviour. Instead, interpret 0 as "no retransmissions needed".

The documentation is updated to explicitly state that setting the timeout to 0 disables retransmission.

Fixes 93f323b9cccc ("mptcp: add a new sysctl add_addr_timeout")
Cc [email protected]
Suggested-by Matthieu Baerts <[email protected]>
Signed-off-by Geliang Tang <[email protected]>
Reviewed-by Matthieu Baerts (NGI0) <[email protected]>
Signed-off-by Matthieu Baerts (NGI0) <[email protected]>
Link https://patch.msgid.link/20250815-net-mptcp-misc-fixes-6-17-rc2-v1-5-521fe9957892@kernel.org open here
Signed-off-by Jakub Kicinski <[email protected]>
[ Apply to net/mptcp/pm_netlink.c , structural changes in mptcp_pm_alloc_anno_list ]
Signed-off-by Sasha Levin <[email protected]>
---
 Documentation/networking/mptcp-sysctl.rst |  2 ++
 net/mptcp/pm_netlink.c                    | 18 ++++++++++++------
 2 files changed, 14 insertions(+), 6 deletions(-)
Documentation/networking/mptcp-sysctl.rst +2 -0
index 95598c21fc8e..09be0e68b9af 100644
@@ -12,6 +12,8 @@ add_addr_timeout - INTEGER (seconds)
 	resent to an MPTCP peer that has not acknowledged a previous
 	ADD_ADDR message.
 
+	Do not retransmit if set to 0.
+
 	The default value matches TCP_RTO_MAX. This is a per-namespace
 	sysctl.
net/mptcp/pm_netlink.c +12 -6
index 2a085ec5bfd0..d7e29583f644 100644
@@ -293,6 +293,7 @@ static void mptcp_pm_add_timer(struct timer_list *timer)
 	struct mptcp_pm_add_entry *entry = from_timer(entry, timer, add_timer);
 	struct mptcp_sock *msk = entry->sock;
 	struct sock *sk = (struct sock *)msk;
+	unsigned int timeout;
 
 	pr_debug("msk=%p\n", msk);
 

@@ -310,6 +311,10 @@ static void mptcp_pm_add_timer(struct timer_list *timer)
 		goto out;
 	}
 
+	timeout = mptcp_get_add_addr_timeout(sock_net(sk));
+	if (!timeout)
+		goto out;
+
 	spin_lock_bh(&msk->pm.lock);
 
 	if (!mptcp_pm_should_add_signal_addr(msk)) {

@@ -321,7 +326,7 @@ static void mptcp_pm_add_timer(struct timer_list *timer)
 
 	if (entry->retrans_times < ADD_ADDR_RETRANS_MAX)
 		sk_reset_timer(sk, timer,
-			       jiffies + mptcp_get_add_addr_timeout(sock_net(sk)));
+			       jiffies + timeout);
 
 	spin_unlock_bh(&msk->pm.lock);
 

@@ -363,6 +368,7 @@ bool mptcp_pm_alloc_anno_list(struct mptcp_sock *msk,
 	struct mptcp_pm_add_entry *add_entry = NULL;
 	struct sock *sk = (struct sock *)msk;
 	struct net *net = sock_net(sk);
+	unsigned int timeout;
 
 	lockdep_assert_held(&msk->pm.lock);
 

@@ -372,9 +378,7 @@ bool mptcp_pm_alloc_anno_list(struct mptcp_sock *msk,
 		if (WARN_ON_ONCE(mptcp_pm_is_kernel(msk)))
 			return false;
 
-		sk_reset_timer(sk, &add_entry->add_timer,
-			       jiffies + mptcp_get_add_addr_timeout(net));
-		return true;
+		goto reset_timer;
 	}
 
 	add_entry = kmalloc(sizeof(*add_entry), GFP_ATOMIC);

@@ -388,8 +392,10 @@ bool mptcp_pm_alloc_anno_list(struct mptcp_sock *msk,
 	add_entry->retrans_times = 0;
 
 	timer_setup(&add_entry->add_timer, mptcp_pm_add_timer, 0);
-	sk_reset_timer(sk, &add_entry->add_timer,
-		       jiffies + mptcp_get_add_addr_timeout(net));
+reset_timer:
+	timeout = mptcp_get_add_addr_timeout(net);
+	if (timeout)
+		sk_reset_timer(sk, &add_entry->add_timer, jiffies + timeout);
 
 	return true;
 }
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