From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mta1.migadu.com (out-73.mta1.migadu.com [95.215.58.73]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 639AC3F9270 for ; Thu, 20 Aug 2026 10:16:36 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=95.215.58.73 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1787221002; cv=none; b=NY9mmYZRybJm8wnInPH0IBX9cprJIF/tlIZB2rMxyYDMDQLskI5s36r/Ua7y8INXGMji8cWY6L8Y/lGIy3ZeeD7lGz9qev2pyprgjKAmZyotbCoKQf6t9YtKbKuxUzzEIaK36mN+Wotr8YonGC05bR0mnNd//OxjCHs2U1YSB+w= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1787221002; c=relaxed/simple; bh=Qd/JI2RknhrDFD1tAjUJMHCGXCHrd2LcWtSrsp+z1N0=; h=MIME-Version:Date:Content-Type:From:Message-ID:Subject:To:Cc: In-Reply-To:References; b=nBMLqbEfUvAhqAUL3f8srs0rFtuiPBwnz8/k0cg481EjzWCmg3AIW1ddkVUb8uVbeUvFqTI0aS0MAArS2MwDnxJPmttRYpU+xPc7tyRn4+SYoi0uoTb9UM16UGup7M7RDcKguUSRy0JbkxiGhsqczk6wN2TXdB57GJFfiBp7HyA= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.dev; spf=pass smtp.mailfrom=linux.dev; dkim=pass (1024-bit key) header.d=linux.dev header.i=@linux.dev header.b=Qj5UxzNB; arc=none smtp.client-ip=95.215.58.73 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.dev Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linux.dev Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux.dev header.i=@linux.dev header.b="Qj5UxzNB" X-Envelope-To: mptcp@lists.linux.dev DKIM-Signature: a=rsa-sha256; bh=Qd/JI2RknhrDFD1tAjUJMHCGXCHrd2LcWtSrsp+z1N0=; c=simple/simple; d=linux.dev; h=from:to:subject:date:message-id:mime-version:content-type; s=key1; t=1787220994; v=1; x=1787825794; b=Qj5UxzNBLUdpm/vaN+4e1rJTM2+2NgpDZQEHhAmSIn4uOzF1E9Xwxew4yRtGy253S+5ftd+b hXHdaNAYX0/d1etIWSWukNQr43aBrSEnd745W30E3vmOgiOTSmib9lthHirCY+MqPzV9T3QgNPi lKK8Ceuud/vN1kNA82aNtxeU= X-Envelope-To: mptcp@lists.linux.dev Received: from webmail.migadu.com (2001:41d0:303:fc7a::) by smtp.migadu.com with ESMTPS id 83f4da997bfb3a62; Thu, 20 Aug 2026 10:16:24 +0000 X-Mizu-Trace-ID: 83f4da997bfb3a62 X-Migadu-Flow: FLOW_OUT Precedence: bulk X-Mailing-List: mptcp@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Date: Thu, 20 Aug 2026 10:16:23 +0000 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable From: gang.yan@linux.dev Message-ID: <74e63e9935103e9fab16ea81e0ea7480f9c7d736@linux.dev> TLS-Required: No Subject: Re: [PATCH mptcp-next v3 5/5] Squash to "mptcp: pm: init and release mptcp_pm_ops" To: "Matthieu Baerts" , sashiko-reviews@lists.linux.dev Cc: mptcp@lists.linux.dev In-Reply-To: References: <20260819125629.49823-1-gang.yan@linux.dev> <20260819125629.49823-6-gang.yan@linux.dev> <20260819131205.3A0201F000E9@smtp.kernel.org> <7b85c6e1e4e270bd368fb7dc6d24279c1c20c3b2@linux.dev> August 20, 2026 at 5:07 PM, "Matthieu Baerts" wrote: > Can you first check if this can happen? I thought that > mptcp_destroy_common would first close all subflows, remove the token, > then release everything linked to the PM =E2=86=92 so the PM will no lo= nger be > called at that point for this msk, right? (I didn't check) > Hi Matt, Thans for looking at this and kindly remind. Yes, I just checked the order you described is right, but I thought it could happen in such order: CPU A (softirq) CPU B(disconnect) ->subflow_token_join_request=20=20=20=20=20=20=20=20=20=20 ->mptcp_token_get_sock() =20 ->mptcp_destroy_common() ->pm_ops_release ->mptcp_pm_get_local_id(): msk->pm.ops->get_local_id() <- NULL deref WDYT? And, I think the window seems too narrow, we may not see it in pra= ctice, maybe a NULL check is enough?=20 Thanks Gang