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 4D3CE26982C for ; Tue, 19 May 2026 00:46:06 +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=1779151567; cv=none; b=YNWVnuHSaBX063ZGW1w98AOMAwluHO8mjoN7wKAdGjUmiPC6S8/TUaYdw8PQLH8tjM/mKV8CHdki1dEucoOvNm8mQ+NrJxZqTMQKO3S9wU06gXRfR79E1EBVK8aG/bKdG8chsxQ9MbyBWCaG0Jrln28RQQ5dOds9W+fleBEqZiQ= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1779151567; c=relaxed/simple; bh=NSOOwsHBwPhV20z5etoBSoP5XMkhRpYyQ1vSSJuK8aY=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=YoqgfM2plrPwyyzQVNitddE/I/uBbGFaIhVgPlOfselJU/VZB8UO5ah7gu8yeg01tN+tAzxGNmPqwr/f2CyG5sy/k8EQssaoD+12vJtAq0THFazgDLhJHvcyYhRNeBNN2Crp52kSOp0vJ5VUa0Mr84LJ2ml5Ccj51DEYsBntiAE= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=azWkq/wa; 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="azWkq/wa" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 3E9C7C2BCB7; Tue, 19 May 2026 00:46:06 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1779151566; bh=NSOOwsHBwPhV20z5etoBSoP5XMkhRpYyQ1vSSJuK8aY=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=azWkq/walH3PpL4B71rsuFyhmj580NMY0sfAVLFCZ65MVExxzrIfldBtUp09KOQ5D jFFs+LxNPXOEBFCblE2NRNmqKNUJr9RGCqmyO5oYRz9pL9ULTQjEI4mFoJYk3+5PIa rlFqvJdtMPlytI0TD944Lk6mbOtsXfwlNkjLVLSzTmIejLGZ2o7f4hAkI2dFtZ3EBd 7s6sqXLZbSW9p7Cg4rRt7Wh+ZLf+84oMCoUFZHEFliQwPam+QH4s4TxclqpXLXjLSw WsCoxu7tLB4H6V/BZ2sHp2rWbzQnUu3RZmUtippgh0Cnx1KaPZCqex1+Rfjjbt26UH LTf1qDzm9GVoA== From: Sasha Levin To: stable@vger.kernel.org Cc: "Matthieu Baerts (NGI0)" , Mat Martineau , Jakub Kicinski , Sasha Levin Subject: [PATCH 5.10.y] mptcp: pm: ADD_ADDR rtx: fix potential data-race Date: Mon, 18 May 2026 20:46:04 -0400 Message-ID: <20260519004604.1930911-1-sashal@kernel.org> X-Mailer: git-send-email 2.53.0 In-Reply-To: <2026051216-clanking-corroding-5130@gregkh> References: <2026051216-clanking-corroding-5130@gregkh> Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit From: "Matthieu Baerts (NGI0)" [ Upstream commit 5cd6e0ad79d2615264f63929f8b457ad97ae550d ] 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) Link: https://patch.msgid.link/20260505-net-mptcp-pm-fixes-7-1-rc3-v1-3-fca8091060a4@kernel.org Signed-off-by: Jakub Kicinski [ relocated change from net/mptcp/pm.c to net/mptcp/pm_netlink.c ] Signed-off-by: Sasha Levin --- net/mptcp/pm_netlink.c | 8 ++++++++ 1 file changed, 8 insertions(+) diff --git a/net/mptcp/pm_netlink.c b/net/mptcp/pm_netlink.c index b88246b8f21c1..d4d56f0af3e0a 100644 --- a/net/mptcp/pm_netlink.c +++ b/net/mptcp/pm_netlink.c @@ -226,6 +226,13 @@ 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(msk)) { sk_reset_timer(sk, timer, jiffies + TCP_RTO_MAX / 8); goto out; @@ -245,6 +252,7 @@ static void mptcp_pm_add_timer(struct timer_list *timer) spin_unlock_bh(&msk->pm.lock); out: + bh_unlock_sock(sk); __sock_put(sk); } -- 2.53.0