From nobody Fri Jun 26 16:28:30 2026 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 420B1480DCF; Tue, 5 May 2026 15:01:34 +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=1777993294; cv=none; b=fvfkar15n/dtzeG3RSZ9Hj2XRxQfv+KByoX19OvPM+VVrxhAIVn2ifvGar7SLpc2EB9oda0CDh1NFIo3D5s0YkkCpNnO/wd7LdX4HXjCQhgdOWCfhZxMAE781FNmhdviXbBhzyhYxHVSiLpYshkuF0YZWYsA34ZFmmrchLFvb+c= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1777993294; c=relaxed/simple; bh=O+sF1GAywSQrGhzPouN65AXm4Ji3EuL/SL0gRQhTA98=; h=From:Date:Subject:MIME-Version:Content-Type:Message-Id:References: In-Reply-To:To:Cc; b=R7dmdnus2Hp0NApwCuzUzAqn5XTkl93bCV3us7+T3gWkhOeVWg/bVS90kUQCGqqJmFHXSN4Jjwa/kNwkBa/s+XtoMR89DyHhPSCwrp6tXnl2TCXij48cBAlyQItsQYNRLIcPmSMsLCWPZxHcH/iGhpN2/+JtuW5qLa2pNockQpc= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=bPDw7r7T; 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="bPDw7r7T" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 206D7C2BCB4; Tue, 5 May 2026 15:01:31 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1777993294; bh=O+sF1GAywSQrGhzPouN65AXm4Ji3EuL/SL0gRQhTA98=; h=From:Date:Subject:References:In-Reply-To:To:Cc:From; b=bPDw7r7TiVLcuOMIhEnhM5wzrqldCztQ+uEjVpv34ydujiF/OWged8icNXp3Akk9Z 9SPWaK6BIOatk2l4M6lXZ6dpR31dkSQjWoZZbUoisUjLcILaECSr98Fgsg9DS11g+2 h9CpK5IKQi3w3gNUiVBxuv/QtaWztsX54V6Wwi8bauSjFyrHwKIV5C8zjhSLuglpXR kX57XL5bTQ6HKgI/7LWGfNAuRJBXUVzSR1dNXGfozBwjuAhm7xisu4jJjo51xrQJXq S8HaoID1UMJOfPr6SEGzMS/eSaJJYWEoWT01iI/0cpSbrERCmn8PNn5QYn6c4vIZrZ tms0uqfOJlV0g== From: "Matthieu Baerts (NGI0)" Date: Tue, 05 May 2026 17:00:51 +0200 Subject: [PATCH net 03/11] mptcp: pm: ADD_ADDR rtx: fix potential data-race Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable Message-Id: <20260505-net-mptcp-pm-fixes-7-1-rc3-v1-3-fca8091060a4@kernel.org> References: <20260505-net-mptcp-pm-fixes-7-1-rc3-v1-0-fca8091060a4@kernel.org> In-Reply-To: <20260505-net-mptcp-pm-fixes-7-1-rc3-v1-0-fca8091060a4@kernel.org> To: Mat Martineau , Geliang Tang , "David S. Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni , Simon Horman , Christoph Paasch Cc: netdev@vger.kernel.org, mptcp@lists.linux.dev, linux-kernel@vger.kernel.org, "Matthieu Baerts (NGI0)" , stable@vger.kernel.org X-Mailer: b4 0.15.2 X-Developer-Signature: v=1; a=openpgp-sha256; l=1279; i=matttbe@kernel.org; h=from:subject:message-id; bh=O+sF1GAywSQrGhzPouN65AXm4Ji3EuL/SL0gRQhTA98=; b=owGbwMvMwCVWo/Th0Gd3rumMp9WSGDJ/sdlqPNZ++flpSWuz2pbOvZ+nTnVJ2ralSfv16pnvl j2bzuT0r6OUhUGMi0FWTJFFui0yf+bzKt4SLz8LmDmsTCBDGLg4BWAij5QZGY4tlL6kw7nnwxNr qcI7fzTbon7W7P2qK52+ne/pu4sFz5YxMhw4ZpVfYF5l6TbHsFDFfsrFE4FWXN1ztl9Qypz/MX/ REU4A 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") Cc: stable@vger.kernel.org Reviewed-by: Mat Martineau 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 5056eb8db24e..3912128d9b86 100644 --- a/net/mptcp/pm.c +++ b/net/mptcp/pm.c @@ -337,6 +337,13 @@ static void mptcp_pm_add_timer(struct timer_list *time= r) if (inet_sk_state_load(sk) =3D=3D TCP_CLOSE) return; =20 + 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; @@ -365,6 +372,7 @@ static void mptcp_pm_add_timer(struct timer_list *timer) mptcp_pm_subflow_established(msk); =20 out: + bh_unlock_sock(sk); __sock_put(sk); } =20 --=20 2.53.0