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 61AF833E34C for ; Wed, 15 Apr 2026 09:58:12 +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=1776247092; cv=none; b=S6UoZrVp/LrAtiWULRIqrvynVfJ/fwI7XQ7H8lyPInE3do1ya9HxFVIQlcVeLVKJJqzOCP6MUJ0UhWG34jxpd4lk4iq09we8pPkoWv8I4FqLIhy7ZLgLEHYtAAIJDdTM6zNGIvG/MfX7IDZ8dwrVKcQGsdVLVnyXhfgRtasNz7E= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1776247092; c=relaxed/simple; bh=xqQ0XziJocJK+T47pPjFZrFCFv0UNP98JJxxWrafiv4=; h=From:Date:Subject:MIME-Version:Content-Type:Message-Id:References: In-Reply-To:To:Cc; b=TbpaYCHqz931UdhAlYc+JYL6oJXax+CzIWjCtfPtUn1r3JsVZbLPJDEqMF5pcuCyzx4FV0PfvwO2ztdqV/jEO5gu2xsUcT4Nz5LC7Z8pA8pV9oBI0qr7GGeDdJmER18MJ0gJXtlnIi8ELlDEYztxqUmeb7IkIC/cLiXLtyTh3D8= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=iZbB2LFD; 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="iZbB2LFD" Received: by smtp.kernel.org (Postfix) with ESMTPSA id C6873C19424; Wed, 15 Apr 2026 09:58:11 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1776247092; bh=xqQ0XziJocJK+T47pPjFZrFCFv0UNP98JJxxWrafiv4=; h=From:Date:Subject:References:In-Reply-To:To:Cc:From; b=iZbB2LFDwenNnnxtLIDEphLz61SzEB96tV7nvw4B544Vm7TAzUyMJ8HJzMQEXg2rX gEm8DkgMQ5iYxVmw8oSv85z35+bI0ZDmW7AWMwRoY6haACNGOrHgHckExNx+vcZMav z2tUvUO7KK3tWen6mTGAvLAoU7+5GDXi7gmg5jCMDvRzCMQnAtWrlbsyVKye7/9bKe UmzYSdU7cKKpPD5lBzDcUE6scvpMM3BgfLFfydBpC7J5iP+BkX6djCdOsV0zfvth5A Z3GkCpavBuryHStDDbdQ2KSycu3/ZFgVv05c+4vfZt91BfSl6Oi8R7OE5kWfR6wEJI fd/rhbRvw5pmA== From: "Matthieu Baerts (NGI0)" Date: Wed, 15 Apr 2026 11:56:50 +0200 Subject: [PATCH mptcp-net v5 02/20] mptcp: pm: ADD_ADDR rtx: fix potential data-race Precedence: bulk X-Mailing-List: mptcp@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Message-Id: <20260415-mptcp-inc-limits-v5-2-e54c3bf80e4e@kernel.org> References: <20260415-mptcp-inc-limits-v5-0-e54c3bf80e4e@kernel.org> In-Reply-To: <20260415-mptcp-inc-limits-v5-0-e54c3bf80e4e@kernel.org> To: MPTCP Upstream Cc: "Matthieu Baerts (NGI0)" X-Mailer: b4 0.15.2 X-Developer-Signature: v=1; a=openpgp-sha256; l=1180; i=matttbe@kernel.org; h=from:subject:message-id; bh=xqQ0XziJocJK+T47pPjFZrFCFv0UNP98JJxxWrafiv4=; b=owGbwMvMwCVWo/Th0Gd3rumMp9WSGDLvJ6q8q7zKN/NBKPv9S9PVPnw/Wv9rzueblWpuc8Wa7 +6dyrwyv6OUhUGMi0FWTJFFui0yf+bzKt4SLz8LmDmsTCBDGLg4BWAiN34y/GaPtjY7nHx966wn TwPYwh+oChY/CF8ns2TCd121svdcez4xMjzdnLO8t97evFPhu0NzpFfmo/kCaqWy8YsMOi68Ujv IwQUA X-Developer-Key: i=matttbe@kernel.org; a=openpgp; fpr=E8CB85F76877057A6E27F77AF6B7824F4269A073 This mptcp_pm_add_timer() helper is executed as a timer callback in softirq context. To avoid any data races, the socket lock needs to be held with bh_lock_sock(). If the socket is in use, retry again soon after, similar to what is done with the keepalive timer. Fixes: 00cfd77b9063 ("mptcp: retransmit ADD_ADDR when timeout") Signed-off-by: Matthieu Baerts (NGI0) --- net/mptcp/pm.c | 8 ++++++++ 1 file changed, 8 insertions(+) diff --git a/net/mptcp/pm.c b/net/mptcp/pm.c index fdadd0e8f77c..43a11b65235f 100644 --- a/net/mptcp/pm.c +++ b/net/mptcp/pm.c @@ -340,6 +340,13 @@ static void mptcp_pm_add_timer(struct timer_list *timer) if (!entry->addr.id) return; + bh_lock_sock(sk); + if (sock_owned_by_user(sk)) { + /* Try again later. */ + sk_reset_timer(sk, timer, jiffies + HZ / 20); + goto out; + } + if (mptcp_pm_should_add_signal_addr(msk)) { sk_reset_timer(sk, timer, jiffies + TCP_RTO_MAX / 8); goto out; @@ -368,6 +375,7 @@ static void mptcp_pm_add_timer(struct timer_list *timer) mptcp_pm_subflow_established(msk); out: + bh_unlock_sock(sk); __sock_put(sk); } -- 2.53.0