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 A686B450909 for ; Mon, 18 May 2026 14:33:58 +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=1779114838; cv=none; b=MHYYODlZGZLVNHKBxVEjYhW/T600xb0mStuDH+oO6gp3C22RC231Zz/I/xRslKDMPgaMqrqzQNOXN9NRJG1/YoASFXd9dWS9m0yfGKFN661rDEAIw1XjD7UVQMM5zNkZWlmDGCdp2Eom2e+yotnC6DuLVTsYgPZGEWWql/svZJw= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1779114838; c=relaxed/simple; bh=WzaHVW83jOy0PuHpPfykt8j3ZpeWrm4os3CFBEZOOaM=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=DK7UkfC202PhRHjmNcw5yXCkP5sXHo8nbkQ2wSFqwhbOQR/XmJEn8FlVchWJssQbYyaq/XKF+G6tQ7xB+3hSg5bPQfhNOLmKNYMLZX2bO24Mg1FJVynEQU2epqQ3iIRtU449iM+GrseHeUx+VyGNYXSneMOYlvL2H0vU+USFg40= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=qQFwvZ+s; 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="qQFwvZ+s" Received: by smtp.kernel.org (Postfix) with ESMTPSA id A79F3C2BCB7; Mon, 18 May 2026 14:33:57 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1779114838; bh=WzaHVW83jOy0PuHpPfykt8j3ZpeWrm4os3CFBEZOOaM=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=qQFwvZ+s1b5EJLsrlLuw4GKvjMGZXs1zS/q7xl3B8kMfJhFZuz+OVpyAOY5f0cwYd Y0NFMDDD2nuuq6eneF9DtcYSR14zvRVAX7POj6bJ0lWcWEyinCJAJaxE+nBsv7KGdu wmswUfOFAzEVyPcTnPCw5KV2a7jn34Fkys6caJXjp53Rs8y23bDmG3YEDab7HtibAX 1dItm7CCagjYHynt05IwJxj43PYyoquP9+tpF2bwJkiXK+UeSq9dLYhSg7aA51+i9D TX58Bjt4+PyibjBMOogLp71JiyAKgObhkwoQX8nOa1kLMcBlXM9IqQrUFCTgZY+AeG WRixycI8e88fA== From: Sasha Levin To: stable@vger.kernel.org Cc: "Matthieu Baerts (NGI0)" , Mat Martineau , Jakub Kicinski , Sasha Levin Subject: [PATCH 6.1.y] mptcp: pm: ADD_ADDR rtx: fix potential data-race Date: Mon, 18 May 2026 10:33:55 -0400 Message-ID: <20260518143355.1341039-1-sashal@kernel.org> X-Mailer: git-send-email 2.53.0 In-Reply-To: <2026051215-bacon-cartoon-33fb@gregkh> References: <2026051215-bacon-cartoon-33fb@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 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 a16a7a538c425..4343d77aed4e9 100644 --- a/net/mptcp/pm_netlink.c +++ b/net/mptcp/pm_netlink.c @@ -318,6 +318,13 @@ 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; @@ -346,6 +353,7 @@ 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