From mboxrd@z Thu Jan 1 00:00:00 1970 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 112B240584E for ; Mon, 18 May 2026 13:05:27 +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=1779109527; cv=none; b=VSZKslmvSbr+h5sppvLB3mzdS/nI/h6o6XkefIH/Ga83kEdupak7CmwcN0oaBQVcmqZ3yhuaIFdRvdy4Uk2sdcUlT15xBRKKcjbFezwCp/owDc+j4IEHoaJ4e+2XG+la02EiGVCXBj7ZWtTYw+J660GlP55zb89k1NcHWfpihZk= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1779109527; c=relaxed/simple; bh=ErLehjKY/7mYaARaC3KyR91rhAIlyonSMzzpgwsg5/s=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=omRlk7+ADYkYQ7uPL7j/YJuZl5w/grk9+pSankOG+VMPkCcre1/wqbmtHa4ybCVNa7B8mGJ2RG7htYUfQuKXQ+AhxfklR4hWhgNocg59dFSGid0avTSW4manUegXZsqgJugC3t6vmghJEwxuDXhymfRHkDHfEbCr4N21Nzyg+iU= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=jf/II2/N; 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="jf/II2/N" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 5616AC2BCB7; Mon, 18 May 2026 13:05:26 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1779109526; bh=ErLehjKY/7mYaARaC3KyR91rhAIlyonSMzzpgwsg5/s=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=jf/II2/NHdBBLmXB1gOLbsx1HFVnNhIANXtxorIlJozF5QuMhSQqcpKHj8ZReC+ND FK/WKDTsntDNJDApbgb5c55RskT2LQPmdF2AfAEFDVQebQeu+4VXyJMQWO4IU6KrGS 5lsk1zoAaLN7xwAg5YjCU/8VfH+Z6kGW14fQXiI4AC+xqRzgLhw8NMD6zO8clC24aF mep1clTI/ZvntHNpywR2WSc9dkT2r0PAWJZUEEYABaUU4VpGV1WNO0nEuS82EC/1f6 2p7uectpByg4FAlRFMv8LiscpQMHy8fKjx54DYUcIVqkaPRKpxGiLRvlacnXxXUR65 NLJdBKi8r9YDw== From: Sasha Levin To: stable@vger.kernel.org Cc: "Matthieu Baerts (NGI0)" , Mat Martineau , Jakub Kicinski , Sasha Levin Subject: [PATCH 6.12.y] mptcp: pm: kernel: correctly retransmit ADD_ADDR ID 0 Date: Mon, 18 May 2026 09:05:24 -0400 Message-ID: <20260518130524.983282-1-sashal@kernel.org> X-Mailer: git-send-email 2.53.0 In-Reply-To: <2026051243-corncob-shrubbery-862b@gregkh> References: <2026051243-corncob-shrubbery-862b@gregkh> Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit From: "Matthieu Baerts (NGI0)" [ Upstream commit b12014d2d36eaed4e4bec5f1ac7e91110eeb100d ] When adding the ADD_ADDR to the list, the address including the IP, port and ID are copied. On the other hand, when the endpoint corresponds to the one from the initial subflow, the ID is set to 0, as specified by the MPTCP protocol. The issue is that the ID was reset after having copied the ID in the ADD_ADDR entry. So the retransmission was done, but using a different ID than the initial one. Fixes: 8b8ed1b429f8 ("mptcp: pm: reuse ID 0 after delete and re-add") Cc: stable@vger.kernel.org Reviewed-by: Mat Martineau Signed-off-by: Matthieu Baerts (NGI0) Link: https://patch.msgid.link/20260505-net-mptcp-pm-fixes-7-1-rc3-v1-1-fca8091060a4@kernel.org Signed-off-by: Jakub Kicinski [ applied to net/mptcp/pm_netlink.c instead of upstream's pm_kernel.c ] Signed-off-by: Sasha Levin --- net/mptcp/pm_netlink.c | 13 ++++++++----- 1 file changed, 8 insertions(+), 5 deletions(-) diff --git a/net/mptcp/pm_netlink.c b/net/mptcp/pm_netlink.c index 3ac09bfe6e4b2..e414e3b7773bd 100644 --- a/net/mptcp/pm_netlink.c +++ b/net/mptcp/pm_netlink.c @@ -590,6 +590,8 @@ static void mptcp_pm_create_subflow_or_signal_addr(struct mptcp_sock *msk) /* check first for announce */ if (msk->pm.add_addr_signaled < add_addr_signal_max) { + u8 endp_id; + /* due to racing events on both ends we can reach here while * previous add address is still running: if we invoke now * mptcp_pm_announce_addr(), that will fail and the @@ -603,19 +605,20 @@ static void mptcp_pm_create_subflow_or_signal_addr(struct mptcp_sock *msk) if (!select_signal_address(pernet, msk, &local)) goto subflow; + /* Special case for ID0: set the correct ID */ + endp_id = local.addr.id; + if (endp_id == msk->mpc_endpoint_id) + local.addr.id = 0; + /* If the alloc fails, we are on memory pressure, not worth * continuing, and trying to create subflows. */ if (!mptcp_pm_alloc_anno_list(msk, &local.addr)) return; - __clear_bit(local.addr.id, msk->pm.id_avail_bitmap); + __clear_bit(endp_id, msk->pm.id_avail_bitmap); msk->pm.add_addr_signaled++; - /* Special case for ID0: set the correct ID */ - if (local.addr.id == msk->mpc_endpoint_id) - local.addr.id = 0; - mptcp_pm_announce_addr(msk, &local.addr, false); mptcp_pm_nl_addr_send_ack(msk); -- 2.53.0