From nobody Wed Sep 17 18:19:19 2025 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id A0C1B301476; Fri, 22 Aug 2025 14:11:40 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1755871900; cv=none; b=j+fM5yQswcBP3QUsc3pmRGPwj1nOb4Yq2IR78at9IMOl6cpeWrmWYWhvEhxJbHxUR/VO1zzi1tFgTYT9qHPYXpNr/rT4E6HYVIMAoDMltWbQJ17FFRoUNEcXKdoRgCMcf6eX7qcNN06CHSAg+OdTEGCRTCAXZtA1T7DKjBoAhfc= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1755871900; c=relaxed/simple; bh=DPH3pE/IpR/sUauAYMSTs2YvC1Rabf+jlHM13SPcVAE=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=NS4r+ryYiV6iZDgnhq4l641nAOLIQgHwvbsmysVycR742Ji9w8o2JnuU8zg0SzG6Xr0vaIlA8mWRLKOwhdVCLfb0Srk/2Nkc0V80M09zFvMRim9IxGb3L2ObBcU1z6xKGOwdslP/+bOh4ZKZtoZSe3VLXt2Ahn1e7NZhsXdO94o= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=c5NAsfWL; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="c5NAsfWL" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 1A6FDC4CEED; Fri, 22 Aug 2025 14:11:38 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1755871900; bh=DPH3pE/IpR/sUauAYMSTs2YvC1Rabf+jlHM13SPcVAE=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=c5NAsfWL5YZ0GNeNILyMe3fSmc4TQ42HtzHQHjkUBDSKaKp5GfCB8LYHLRbN95zwm DHidrz2sAKN6qd+e4IEUUxd24D7JqN1FMaGfKSEUQ6xBKw3VguOzmmq3BR5PLNJpIj 9razyKwur01D7lcdSNR4PHU1zyZ7g7M4TKqxNE02AePRXRh0MUIEUZrxla37DRqDH3 7w221TrpdFJ6mQJGLySV4qwd2fO8kYWMq6tZ0ECQFxWdivbWPUq/3I8EVDwG86Jjp1 bFAP1e/tmFgNXAxhKECXeqN5HnatP9dovAzKxaTxL8/cxxxEFJIw6fb2rcv3uKMbDM N3c28/6ZFsVvQ== From: "Matthieu Baerts (NGI0)" To: mptcp@lists.linux.dev, stable@vger.kernel.org, gregkh@linuxfoundation.org Cc: Geliang Tang , sashal@kernel.org, Matthieu Baerts , Jakub Kicinski Subject: [PATCH 6.1.y 2/3] mptcp: disable add_addr retransmission when timeout is 0 Date: Fri, 22 Aug 2025 16:11:27 +0200 Message-ID: <20250822141124.49727-7-matttbe@kernel.org> X-Mailer: git-send-email 2.50.0 In-Reply-To: <20250822141124.49727-5-matttbe@kernel.org> References: <20250822141124.49727-5-matttbe@kernel.org> Precedence: bulk X-Mailing-List: mptcp@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Developer-Signature: v=1; a=openpgp-sha256; l=3467; i=matttbe@kernel.org; h=from:subject; bh=xq0E52XpZNwSZtXFiRZqObJZaOBTpWGLcJv/JmPWX5g=; b=owGbwMvMwCVWo/Th0Gd3rumMp9WSGDJWVE043uTyJnWiwkMVD6X8G9FbAjtiX9SJ+d89bL4jT XXXkvqnHaUsDGJcDLJiiizSbZH5M59X8ZZ4+VnAzGFlAhnCwMUpABNZmcPI8DV7x3bNhTypSWKH Jbn4L8xy218oJ7Do4dMIVrllC5TqljD8D3j9L2XljXzBWwy9TLWhMlw/uHQfbEk7tExB+oX6hFk 7OAA= X-Developer-Key: i=matttbe@kernel.org; a=openpgp; fpr=E8CB85F76877057A6E27F77AF6B7824F4269A073 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" From: Geliang Tang commit f5ce0714623cffd00bf2a83e890d09c609b7f50a upstream. 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: stable@vger.kernel.org Suggested-by: Matthieu Baerts Signed-off-by: Geliang Tang Reviewed-by: Matthieu Baerts (NGI0) Signed-off-by: Matthieu Baerts (NGI0) Link: https://patch.msgid.link/20250815-net-mptcp-misc-fixes-6-17-rc2-v1-5-= 521fe9957892@kernel.org Signed-off-by: Jakub Kicinski [ Before commit e4c28e3d5c09 ("mptcp: pm: move generic PM helpers to pm.c"), mptcp_pm_alloc_anno_list() was in pm_netlink.c. The same patch can be applied there without conflicts. ] Signed-off-by: Matthieu Baerts (NGI0) --- Documentation/networking/mptcp-sysctl.rst | 2 ++ net/mptcp/pm_netlink.c | 13 ++++++++++--- 2 files changed, 12 insertions(+), 3 deletions(-) diff --git a/Documentation/networking/mptcp-sysctl.rst b/Documentation/netw= orking/mptcp-sysctl.rst index 213510698014..722b4395e91b 100644 --- a/Documentation/networking/mptcp-sysctl.rst +++ b/Documentation/networking/mptcp-sysctl.rst @@ -20,6 +20,8 @@ add_addr_timeout - INTEGER (seconds) resent to an MPTCP peer that has not acknowledged a previous ADD_ADDR message. =20 + Do not retransmit if set to 0. + The default value matches TCP_RTO_MAX. This is a per-namespace sysctl. =20 diff --git a/net/mptcp/pm_netlink.c b/net/mptcp/pm_netlink.c index 59d6e701d854..cf9244a3644f 100644 --- a/net/mptcp/pm_netlink.c +++ b/net/mptcp/pm_netlink.c @@ -304,6 +304,7 @@ static void mptcp_pm_add_timer(struct timer_list *timer) struct mptcp_pm_add_entry *entry =3D from_timer(entry, timer, add_timer); struct mptcp_sock *msk =3D entry->sock; struct sock *sk =3D (struct sock *)msk; + unsigned int timeout; =20 pr_debug("msk=3D%p\n", msk); =20 @@ -321,6 +322,10 @@ static void mptcp_pm_add_timer(struct timer_list *time= r) goto out; } =20 + timeout =3D mptcp_get_add_addr_timeout(sock_net(sk)); + if (!timeout) + goto out; + spin_lock_bh(&msk->pm.lock); =20 if (!mptcp_pm_should_add_signal_addr(msk)) { @@ -332,7 +337,7 @@ static void mptcp_pm_add_timer(struct timer_list *timer) =20 if (entry->retrans_times < ADD_ADDR_RETRANS_MAX) sk_reset_timer(sk, timer, - jiffies + mptcp_get_add_addr_timeout(sock_net(sk))); + jiffies + timeout); =20 spin_unlock_bh(&msk->pm.lock); =20 @@ -374,6 +379,7 @@ bool mptcp_pm_alloc_anno_list(struct mptcp_sock *msk, struct mptcp_pm_add_entry *add_entry =3D NULL; struct sock *sk =3D (struct sock *)msk; struct net *net =3D sock_net(sk); + unsigned int timeout; =20 lockdep_assert_held(&msk->pm.lock); =20 @@ -398,8 +404,9 @@ bool mptcp_pm_alloc_anno_list(struct mptcp_sock *msk, =20 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 =3D mptcp_get_add_addr_timeout(net); + if (timeout) + sk_reset_timer(sk, &add_entry->add_timer, jiffies + timeout); =20 return true; } --=20 2.50.0