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 BD9ED1DE4E0 for ; Sun, 12 Apr 2026 05:17:35 +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=1775971055; cv=none; b=nL9wuJrgxnDWZZNHrxWWjqITQOTEV8DVLkoaKcj6RtdOTE/MqJJGUz6GH4GaNGLCL/jP7dN9yoG1lF8XxJ3za8M5+v/jU/8/bFNiFzq5l2GYgZ1ADf+IgmIiPbxyMfRykR5WqLR/TPvUnqd4uPf9hiY/rgJSa5J1PKnrpgap7eA= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1775971055; c=relaxed/simple; bh=AVDtBQNstLZ20HiUsQtgX1j1YeHtNkG87qisyabwY8o=; h=Subject:To:Cc:From:Date:Message-ID:MIME-Version:Content-Type; b=dgH+UIZhFGKwz2XD0Xub7ag4hQ4sIap16uAkT1jbWiMIX5gcfS7GP7uQf34+XIlzn8d/osIV9FDAe44yqqxjVrnSWSt4Lv3EWd9l+NYZqb6Pl+GPEtLbrxGjU9F0TeuEUoQyqfblK2L3z/Tz8XVkuRK9GdRXczULB/DTfbr64Fo= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=UW5+1LiJ; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="UW5+1LiJ" Received: by smtp.kernel.org (Postfix) with ESMTPSA id ED038C19424; Sun, 12 Apr 2026 05:17:34 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1775971055; bh=AVDtBQNstLZ20HiUsQtgX1j1YeHtNkG87qisyabwY8o=; h=Subject:To:Cc:From:Date:From; b=UW5+1LiJMHnwDVBVAiHOxn2z7fn1AIpbyn//nOgsn4+omx7rUQDSWCeYX2cy38o6O +yOnsMZkghU8CbzaJLXTO+nvwJGsGtm3bOGmZkhBD0PZgfgB7CeZ49No79Gnd1achJ tTVSoOtr+/SVaSRbxNfy+XfPz75HfGxEw62u/mp4= Subject: FAILED: patch "[PATCH] Revert "mptcp: add needs_id for netlink appending addr"" failed to apply to 6.6-stable tree To: matttbe@kernel.org,geliang@kernel.org,kuba@kernel.org Cc: From: Date: Sun, 12 Apr 2026 07:17:24 +0200 Message-ID: <2026041224-kinfolk-mustiness-e33d@gregkh> Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=ANSI_X3.4-1968 Content-Transfer-Encoding: 8bit The patch below does not apply to the 6.6-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 . 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-6.6.y git checkout FETCH_HEAD git cherry-pick -x 8e2760eaab778494fc1fa257031e0e1799647f46 # git commit -s git send-email --to '' --in-reply-to '2026041224-kinfolk-mustiness-e33d@gregkh' --subject-prefix 'PATCH 6.6.y' HEAD^.. Possible dependencies: thanks, greg k-h ------------------ original commit in Linus's tree ------------------ >From 8e2760eaab778494fc1fa257031e0e1799647f46 Mon Sep 17 00:00:00 2001 From: "Matthieu Baerts (NGI0)" Date: Tue, 7 Apr 2026 10:41:41 +0200 Subject: [PATCH] Revert "mptcp: add needs_id for netlink appending addr" This commit was originally adding the ability to add MPTCP endpoints with ID 0 by accident. The in-kernel PM, handling MPTCP endpoints at the net namespace level, is not supposed to handle endpoints with such ID, because this ID 0 is reserved to the initial subflow, as mentioned in the MPTCPv1 protocol [1], a per-connection setting. Note that 'ip mptcp endpoint add id 0' stops early with an error, but other tools might still request the in-kernel PM to create MPTCP endpoints with this restricted ID 0. In other words, it was wrong to call the mptcp_pm_has_addr_attr_id helper to check whether the address ID attribute is set: if it was set to 0, a new MPTCP endpoint would be created with ID 0, which is not expected, and might cause various issues later. Fixes: 584f38942626 ("mptcp: add needs_id for netlink appending addr") Cc: stable@vger.kernel.org Link: https://datatracker.ietf.org/doc/html/rfc8684#section-3.2-9 [1] Reviewed-by: Geliang Tang Signed-off-by: Matthieu Baerts (NGI0) Link: https://patch.msgid.link/20260407-net-mptcp-revert-pm-needs-id-v2-1-7a25cbc324f8@kernel.org Signed-off-by: Jakub Kicinski diff --git a/net/mptcp/pm_kernel.c b/net/mptcp/pm_kernel.c index 82e59f9c6dd9..0ebf43be9939 100644 --- a/net/mptcp/pm_kernel.c +++ b/net/mptcp/pm_kernel.c @@ -720,7 +720,7 @@ static void __mptcp_pm_release_addr_entry(struct mptcp_pm_addr_entry *entry) static int mptcp_pm_nl_append_new_local_addr(struct pm_nl_pernet *pernet, struct mptcp_pm_addr_entry *entry, - bool needs_id, bool replace) + bool replace) { struct mptcp_pm_addr_entry *cur, *del_entry = NULL; int ret = -EINVAL; @@ -779,7 +779,7 @@ static int mptcp_pm_nl_append_new_local_addr(struct pm_nl_pernet *pernet, } } - if (!entry->addr.id && needs_id) { + if (!entry->addr.id) { find_next: entry->addr.id = find_next_zero_bit(pernet->id_bitmap, MPTCP_PM_MAX_ADDR_ID + 1, @@ -790,7 +790,7 @@ static int mptcp_pm_nl_append_new_local_addr(struct pm_nl_pernet *pernet, } } - if (!entry->addr.id && needs_id) + if (!entry->addr.id) goto out; __set_bit(entry->addr.id, pernet->id_bitmap); @@ -923,7 +923,7 @@ int mptcp_pm_nl_get_local_id(struct mptcp_sock *msk, return -ENOMEM; entry->addr.port = 0; - ret = mptcp_pm_nl_append_new_local_addr(pernet, entry, true, false); + ret = mptcp_pm_nl_append_new_local_addr(pernet, entry, false); if (ret < 0) kfree(entry); @@ -977,18 +977,6 @@ static int mptcp_nl_add_subflow_or_signal_addr(struct net *net, return 0; } -static bool mptcp_pm_has_addr_attr_id(const struct nlattr *attr, - struct genl_info *info) -{ - struct nlattr *tb[MPTCP_PM_ADDR_ATTR_MAX + 1]; - - if (!nla_parse_nested_deprecated(tb, MPTCP_PM_ADDR_ATTR_MAX, attr, - mptcp_pm_address_nl_policy, info->extack) && - tb[MPTCP_PM_ADDR_ATTR_ID]) - return true; - return false; -} - /* Add an MPTCP endpoint */ int mptcp_pm_nl_add_addr_doit(struct sk_buff *skb, struct genl_info *info) { @@ -1037,9 +1025,7 @@ int mptcp_pm_nl_add_addr_doit(struct sk_buff *skb, struct genl_info *info) goto out_free; } } - ret = mptcp_pm_nl_append_new_local_addr(pernet, entry, - !mptcp_pm_has_addr_attr_id(attr, info), - true); + ret = mptcp_pm_nl_append_new_local_addr(pernet, entry, true); if (ret < 0) { GENL_SET_ERR_MSG_FMT(info, "too many addresses or duplicate one: %d", ret); goto out_free;