From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 24E8FC4332F for ; Sun, 29 Oct 2023 23:07:32 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231972AbjJ2XHb (ORCPT ); Sun, 29 Oct 2023 19:07:31 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:35136 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232110AbjJ2XGx (ORCPT ); Sun, 29 Oct 2023 19:06:53 -0400 Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 8A728619C; Sun, 29 Oct 2023 16:01:03 -0700 (PDT) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 97180C4AF5C; Sun, 29 Oct 2023 22:59:38 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1698620379; bh=kmYEwctVNjlIao9AFHKGbKqV/mzm7hbC9f6dmckWLcc=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=Ms5RAw4KR09EyGRQ5YTvo07VxmKCgYtpWWPMMgvVmF/1VWQ2DaRRSWzt8e/6fbnLT Vqd5gnFIZJnskIwreKiuaK0ZBrQsV2mAD+imISGWHpmevuNXb0u4CeCsuU9MXD+xiJ qVrnXZswbMv9jj51mV835jWKLcbYNzbRMshs0zsc7RYAAHlVBFcxS7yxSIINYvlOJM 5JPfnYGOwnNgW12YaAq0IAnTL/0zgyfgAuqFdWL1WjFIFQ07fHsnKP3eVspEQFEXpE +//736OuV2pnVgpX7cQdwx9UmI1XsXT82sAUPu1iSPC6f3+Y6NlWKCkxDufLUyiNf5 /pDfSvxtvQ1DA== From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Arkadiusz Bokowy , Luiz Augusto von Dentz , Sasha Levin , marcel@holtmann.org, johan.hedberg@gmail.com, luiz.dentz@gmail.com, linux-bluetooth@vger.kernel.org Subject: [PATCH AUTOSEL 5.15 16/28] Bluetooth: vhci: Fix race when opening vhci device Date: Sun, 29 Oct 2023 18:58:51 -0400 Message-ID: <20231029225916.791798-16-sashal@kernel.org> X-Mailer: git-send-email 2.42.0 In-Reply-To: <20231029225916.791798-1-sashal@kernel.org> References: <20231029225916.791798-1-sashal@kernel.org> MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore X-stable-base: Linux 5.15.137 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Arkadiusz Bokowy [ Upstream commit 92d4abd66f7080075793970fc8f241239e58a9e7 ] When the vhci device is opened in the two-step way, i.e.: open device then write a vendor packet with requested controller type, the device shall respond with a vendor packet which includes HCI index of created interface. When the virtual HCI is created, the host sends a reset request to the controller. This request is processed by the vhci_send_frame() function. However, this request is send by a different thread, so it might happen that this HCI request will be received before the vendor response is queued in the read queue. This results in the HCI vendor response and HCI reset request inversion in the read queue which leads to improper behavior of btvirt: > dmesg [1754256.640122] Bluetooth: MGMT ver 1.22 [1754263.023806] Bluetooth: MGMT ver 1.22 [1754265.043775] Bluetooth: hci1: Opcode 0x c03 failed: -110 In order to synchronize vhci two-step open/setup process with virtual HCI initialization, this patch adds internal lock when queuing data in the vhci_send_frame() function. Signed-off-by: Arkadiusz Bokowy Signed-off-by: Luiz Augusto von Dentz Signed-off-by: Sasha Levin --- drivers/bluetooth/hci_vhci.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/drivers/bluetooth/hci_vhci.c b/drivers/bluetooth/hci_vhci.c index 8469f9876dd26..31d70bad83d29 100644 --- a/drivers/bluetooth/hci_vhci.c +++ b/drivers/bluetooth/hci_vhci.c @@ -67,7 +67,10 @@ static int vhci_send_frame(struct hci_dev *hdev, struct sk_buff *skb) struct vhci_data *data = hci_get_drvdata(hdev); memcpy(skb_push(skb, 1), &hci_skb_pkt_type(skb), 1); + + mutex_lock(&data->open_mutex); skb_queue_tail(&data->readq, skb); + mutex_unlock(&data->open_mutex); wake_up_interruptible(&data->read_wait); return 0; -- 2.42.0