From nobody Thu Oct 2 09:16:53 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 BB9CD2FE594; Thu, 18 Sep 2025 08:51:30 +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=1758185490; cv=none; b=Hjwvzgw6y8winIqgNtoBFEUf6xYLeWtmt8SC6XkkpHIPTFz4wc+jqCwX0OXeobys6Y19ihDzRwSP/iFEP3gX9b4kG/Ksv6jQkB8DnHlHzP+ymMtd6G0nocYligOZfLMtGvnpHZtc1hNbh4C6yA9O9WqX5iSQs7m2VXNsmaSeqgg= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1758185490; c=relaxed/simple; bh=EOhcyQviMMRhx2W39PIzcaMVrFvf9rRwgBG7ZlEa5Qk=; h=From:Date:Subject:MIME-Version:Content-Type:Message-Id:To:Cc; b=niAkxSFmXvPA00pic9rjsnVSPtdUvh5W9NLJgwYlECWOcQCWgMKX7DsDorqTzB9yzk5ZMEyeWqwm9Pmm32YmnRoBBeWgIv4A542FFLiTr3su3yDaexf160dW3Ds8XZJ9+ut+NyZczFlLTHVkJdbwTpT28b0/iMnT8wwsROUKUP0= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=rrWsTO03; 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="rrWsTO03" Received: by smtp.kernel.org (Postfix) with ESMTPSA id EFF19C4CEF7; Thu, 18 Sep 2025 08:51:27 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1758185490; bh=EOhcyQviMMRhx2W39PIzcaMVrFvf9rRwgBG7ZlEa5Qk=; h=From:Date:Subject:To:Cc:From; b=rrWsTO03uNLR2OpUo2Y+lCxaOienaLS0y3f5lE2pdbvNZrvJ9gXyEgyx6CNIHoCn/ CeNwxbahgBoqvIm/FxvphGRWISHEdb8kzeOvArQLXBzZNZ4tZS9WCNn5yuifS75F/h G6vg04mIcgPZ9DHskv7HAl30TAzDvSdWpKAvAfwTH3rEPmVVAG1sb6902PZMszKkeL Mh9A9WvXDPFlxRHoLckAeMl143/a1IM8Gend6hpFpgK2va6LsQ57pYlbIM6a57UWR9 b6Yd615bm8+ygtDJvLSccESMHjHv3SZ4kUk+5sZA0oN5QHvMwrFK/7uVhAgyKZkJI+ CrwSaTPPanSQg== From: "Matthieu Baerts (NGI0)" Date: Thu, 18 Sep 2025 10:50:18 +0200 Subject: [PATCH net-next] mptcp: reset blackhole on success with non-loopback ifaces Precedence: bulk X-Mailing-List: mptcp@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable Message-Id: <20250918-net-next-mptcp-blackhole-reset-loopback-v1-1-bf5818326639@kernel.org> X-B4-Tracking: v=1; b=H4sIAMnHy2gC/zWNwQqDMBBEf0X23IUkVIj+SulB46qLaRKSUATx3 10ED3N4M/DmgEKZqUDfHJDpz4VjENCvBtw6hIWQJ2EwyrSq0xYDVcle8ZeqSzj6wW1r9ISZikw +xjRKhZM1rtWW3qqbQWwp08z7/fSBRwLf87wAanYj6IMAAAA= X-Change-ID: 20250918-net-next-mptcp-blackhole-reset-loopback-d82c518e409f To: Mat Martineau , Geliang Tang , "David S. Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni , Simon Horman Cc: netdev@vger.kernel.org, mptcp@lists.linux.dev, linux-kernel@vger.kernel.org, stable@vger.kernel.org, "Matthieu Baerts (NGI0)" , Kuniyuki Iwashima X-Mailer: b4 0.14.2 X-Developer-Signature: v=1; a=openpgp-sha256; l=2035; i=matttbe@kernel.org; h=from:subject:message-id; bh=EOhcyQviMMRhx2W39PIzcaMVrFvf9rRwgBG7ZlEa5Qk=; b=owGbwMvMwCVWo/Th0Gd3rumMp9WSGDJOn+Cbx3R/a6HmPg7hL8vc48p7vu/ViJORv6Q589HC0 xPiOWuyOkpZGMS4GGTFFFmk2yLzZz6v4i3x8rOAmcPKBDKEgYtTACZyPJaR4YRHFLd78r/U1cmt 927t4DXVYLR7+e7qhQ0rWKsjZ4XaVjEyXM8u37p/S6S0h+qvmCq9N/+FW9TvpCoXMAjVLmLJff2 fFwA= X-Developer-Key: i=matttbe@kernel.org; a=openpgp; fpr=E8CB85F76877057A6E27F77AF6B7824F4269A073 When a first MPTCP connection gets successfully established after a blackhole period, 'active_disable_times' was supposed to be reset when this connection was done via any non-loopback interfaces. Unfortunately, the opposite condition was checked: only reset when the connection was established via a loopback interface. Fixing this by simply looking at the opposite. This is similar to what is done with TCP FastOpen, see tcp_fastopen_active_disable_ofo_check(). This patch is a follow-up of a previous discussion linked to commit 893c49a78d9f ("mptcp: Use __sk_dst_get() and dst_dev_rcu() in mptcp_active_enable()."), see [1]. Fixes: 27069e7cb3d1 ("mptcp: disable active MPTCP in case of blackhole") Cc: stable@vger.kernel.org Link: https://lore.kernel.org/4209a283-8822-47bd-95b7-87e96d9b7ea3@kernel.o= rg [1] Signed-off-by: Matthieu Baerts (NGI0) Reviewed-by: Kuniyuki Iwashima Reviewed-by: Simon Horman --- Cc: Kuniyuki Iwashima Note: sending this fix to net-next, similar to commits 108a86c71c93 ("mptcp: Call dst_release() in mptcp_active_enable().") and 893c49a78d9f ("mptcp: Use __sk_dst_get() and dst_dev_rcu() in mptcp_active_enable()."). Also to avoid conflicts, and because we are close to the merge windows. --- net/mptcp/ctrl.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/net/mptcp/ctrl.c b/net/mptcp/ctrl.c index e8ffa62ec183f3cd8156e3969ac4a7d0213a990b..d96130e49942e2fb878cd1897ad= 43c1d420fb233 100644 --- a/net/mptcp/ctrl.c +++ b/net/mptcp/ctrl.c @@ -507,7 +507,7 @@ void mptcp_active_enable(struct sock *sk) rcu_read_lock(); dst =3D __sk_dst_get(sk); dev =3D dst ? dst_dev_rcu(dst) : NULL; - if (dev && (dev->flags & IFF_LOOPBACK)) + if (!(dev && (dev->flags & IFF_LOOPBACK))) atomic_set(&pernet->active_disable_times, 0); rcu_read_unlock(); } --- base-commit: b127e355f1af1e4a635ed8f78cb0d11c916613cf change-id: 20250918-net-next-mptcp-blackhole-reset-loopback-d82c518e409f Best regards, --=20 Matthieu Baerts (NGI0)