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 0D0F123D7E3; Mon, 13 Apr 2026 16:04:32 +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=1776096272; cv=none; b=i73tOWkj7e+0Pkol9f+tQEZEE6N2v3A/7AHNU+J96xI3s1c47iDkrKB7PW5Npkd+UV1ZaQCr5wHnclberXjJZ1saKg7iiS5T1sHjn3MsTvFEgNwHcDRX+7Vubgn+bdbTTya9YCci+P/JizlM6X6UsFJ+Eh5duY2+i+q3mpuPWIw= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1776096272; c=relaxed/simple; bh=SZdcB+0kEWDohbZFs5gNQjkAWze86wFdSyjznNCJb4s=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=B0TE1AgmqhlMGSdfjvNs4DUVcVIFjVpZkVgQPR5lgplubYsyDQ8W+1STHAw14o1x3r+TFmo24SbSTjHbaQkgd2SPHPaSO/wH6x8Fm4I15zVJFDO3tyYWzyCng0mZIIOgQuuvMuXy3zzdaAlG3Uu1JJjos6rDCliyx8mOiXqbQYE= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=KXTkbK39; 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="KXTkbK39" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 96D4DC2BCAF; Mon, 13 Apr 2026 16:04:31 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1776096271; bh=SZdcB+0kEWDohbZFs5gNQjkAWze86wFdSyjznNCJb4s=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=KXTkbK39U+vKkVG5+b5rU18zsnK6J20W2LpHWOyWndo5dykAovLMYNJXXdPLl5w7k iPcjGCNr7eMVtF2MtREIBWI47+P3izwSWWFisRO8vBltCMy6F5+dLxMpMAiBx2/8T1 iQcxkGeZtmi4xJynkCxTtoD/bT9xINHbUS3uiUuE= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Geliang Tang , "Matthieu Baerts (NGI0)" , Jakub Kicinski Subject: [PATCH 6.19 07/86] Revert "mptcp: add needs_id for netlink appending addr" Date: Mon, 13 Apr 2026 17:59:14 +0200 Message-ID: <20260413155731.848141693@linuxfoundation.org> X-Mailer: git-send-email 2.53.0 In-Reply-To: <20260413155731.568515178@linuxfoundation.org> References: <20260413155731.568515178@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.19-stable review patch. If anyone has any objections, please let me know. ------------------ From: Matthieu Baerts (NGI0) commit 8e2760eaab778494fc1fa257031e0e1799647f46 upstream. 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 Signed-off-by: Greg Kroah-Hartman --- net/mptcp/pm_kernel.c | 24 +++++------------------- 1 file changed, 5 insertions(+), 19 deletions(-) --- a/net/mptcp/pm_kernel.c +++ b/net/mptcp/pm_kernel.c @@ -720,7 +720,7 @@ static void __mptcp_pm_release_addr_entr 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_ } } - 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 @@ find_next: } } - 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 mptc 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 @@ next: 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_ 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;