From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (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 763534B0E2C for ; Wed, 16 Sep 2026 16:34:21 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1789576464; cv=none; b=haHM/s4d2oXmkfoyBKnTLnswHVNxgecszo6xqtJzfSn/CwSpQ27BOMNM4GqtpknqaA3Fb3xGrEshKIEdbbdnYCRg1AV5MtnkjYhqVfOCg1gZzU3pEeEmeNSampA9Trz+1S2Q/Y4eibIsNi0nhvb5xQo76VUtpDqCJv87KswR9qY= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1789576464; c=relaxed/simple; bh=ZPfBmzNxv17bJULroEpAJtXvxJxAjkT/bWoorI2BS+E=; h=Subject:To:Cc:From:Date:Message-ID:MIME-Version:Content-Type; b=ZWXHOqt+X6joeYtQr/dlnD6Kl2o6vwYzIZxab21QQG9I7AOMFVYR77f8CVzBVnVASCBqNx/GZC3NgDNLwd3o4+oy8MqPi+dQ69hQPHL1e0W5j1K26pT3vaXLelcoXGxXezvebIMw1qi94b6jlKiYL6rUbD2H1YX0NJbpti+nawc= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=JArQEClB; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="JArQEClB" Received: by smtp.kernel.org (Postfix) with ESMTPSA id E3B521F00898; Wed, 16 Sep 2026 16:34:18 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1789576459; bh=PUd1pBhZ666Jcm6eqg/pbpxo4sS3rFuNOglPSk5Tdsw=; h=Subject:To:Cc:From:Date; b=JArQEClBp8oz0jJ3V2xpuLjVjrOzVGFdq3+gEN9PKPFc+ZyXZaPL/j7tV44PHrPo2 2jeQlcJTditmogqd6avSgTEE7EVpr3WKsgpZ3J13UmJwqk9YXZwd3bmrGMrzGW5/ad 5eqsZsNiQLrRJp/LaxCQeNTWuOfb1FXld3T/FcDY= Subject: FAILED: patch "[PATCH] mptcp: pm: kernel: drop pending ADD_ADDR when removing ID0" failed to apply to 6.12-stable tree To: kalpan.jani@mpiricsoftware.com,cuitao@kylinos.cn,kuba@kernel.org,matttbe@kernel.org Cc: From: Date: Wed, 16 Sep 2026 17:31:02 +0100 Message-ID: <2026091602-garbage-gumdrop-1752@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 6.12-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-6.12.y git checkout FETCH_HEAD git cherry-pick -x 2ac7d6e620764f1fc79eb4edd3610a7a661981ca # git commit -s git send-email --to '' --in-reply-to '2026091602-garbage-gumdrop-1752@gregkh' --subject-prefix 'PATCH 6.12.y' 'HEAD^..' Possible dependencies: thanks, greg k-h ------------------ original commit in Linus's tree ------------------ >From 2ac7d6e620764f1fc79eb4edd3610a7a661981ca Mon Sep 17 00:00:00 2001 From: Kalpan Jani Date: Tue, 8 Sep 2026 16:07:09 +0200 Subject: [PATCH] mptcp: pm: kernel: drop pending ADD_ADDR when removing ID0 The in-kernel MPTCP path manager can leave a stale ADD_ADDR announcement entry alive when removing the id 0 endpoint. This happens because the id 0 removal path does not tear down pending announcements, unlike the non-zero id path. When the PM later reselects id 0 after adding another signal endpoint, it finds the stale anno_list entry and hits WARN_ON_ONCE(mptcp_pm_is_kernel()) in mptcp_pm_announced_alloc(). Root cause: asymmetry between removal paths. - Non-zero id path: mptcp_nl_remove_subflow_and_signal_addr() calls mptcp_pm_remove_announced() to clean up. - Id 0 path: mptcp_nl_remove_id_zero_address() skips cleanup entirely. Fix by making the id 0 path symmetric: call mptcp_pm_announced_remove() and decrement add_addr_signaled before queuing the RM_ADDR. Subtle detail: signal endpoints are stored in anno_list with port 0, but msk_local carries the connection's local port. In other words, entries linked to ID0 paths should have port == 0. A follow-up patch will ensure that. mptcp_pm_announced_remove() uses use_port=true for comparison. So clear the port before the lookup. Fixes: 740d798e8767 ("mptcp: remove id 0 address") Cc: stable@vger.kernel.org Reported-by: syzbot+55c2a5c871441261ed14@syzkaller.appspotmail.com Closes: https://github.com/multipath-tcp/mptcp_net-next/issues/620 Suggested-by: Tao Cui Signed-off-by: Kalpan Jani Reviewed-by: Matthieu Baerts (NGI0) Signed-off-by: Matthieu Baerts (NGI0) Link: https://patch.msgid.link/20260908-net-mptcp-misc-fixes-7-3-rc1-v2-4-df1de70348b6@kernel.org Signed-off-by: Jakub Kicinski diff --git a/net/mptcp/pm_kernel.c b/net/mptcp/pm_kernel.c index 424f1a7f9248..1a7750813235 100644 --- a/net/mptcp/pm_kernel.c +++ b/net/mptcp/pm_kernel.c @@ -1137,6 +1137,8 @@ static int mptcp_nl_remove_id_zero_address(struct net *net, while ((msk = mptcp_token_iter_next(net, &s_slot, &s_num)) != NULL) { struct sock *sk = (struct sock *)msk; struct mptcp_addr_info msk_local; + struct mptcp_addr_info anno_addr; + bool announced; if (list_empty(&msk->conn_list) || mptcp_pm_is_userspace(msk)) goto next; @@ -1146,7 +1148,13 @@ static int mptcp_nl_remove_id_zero_address(struct net *net, goto next; lock_sock(sk); + /* Drop a possibly pending ADD_ADDR for this address. */ + anno_addr = msk_local; + anno_addr.port = 0; + announced = mptcp_pm_announced_remove(msk, &anno_addr); spin_lock_bh(&msk->pm.lock); + if (announced) + msk->pm.add_addr_signaled--; mptcp_pm_remove_addr(msk, &list); mptcp_pm_rm_subflow(msk, &list); __mark_subflow_endp_available(msk, 0);