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 193F2C4332F for ; Sun, 29 Oct 2023 23:36:08 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231271AbjJ2XgG (ORCPT ); Sun, 29 Oct 2023 19:36:06 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:35208 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232005AbjJ2XEF (ORCPT ); Sun, 29 Oct 2023 19:04:05 -0400 Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 022007DA0; Sun, 29 Oct 2023 16:02:19 -0700 (PDT) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 77D3CC116C8; Sun, 29 Oct 2023 23:00:24 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1698620425; bh=kmYEwctVNjlIao9AFHKGbKqV/mzm7hbC9f6dmckWLcc=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=jXBp474wQHKtTmmrRHeJOyA1yPap+Qhu13ortTNqE8y6qW6/wHBl8NNLBcY3R2Psq SwSfDqj3EcpkQxovbCTi6YrfINasiMD9/IVD4wBX6s9OoOu8KLPwS0AlQmzEQxMSBj +3Jzee0VfvHVv0E4oC4XkblPOokg8zwNvsqgbHLbf2ExDITm7p7VtmVUp+JICN1LmN UQeRQ5nrCZUxqa8aqc27HFjeh3ZcGiizFO4YBZ/aZRuUa4aZjfmk7WFZZGVfp4Eq5s H0ow+RiMor3GHmnS8hm5Cw9sHv9c6866oVF/CDejl0FvfMfqc2trVte9ro82q+Tl1J 6gM09Hcb7Llbg== 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 5.10 06/16] Bluetooth: vhci: Fix race when opening vhci device Date: Sun, 29 Oct 2023 18:59:52 -0400 Message-ID: <20231029230014.792490-6-sashal@kernel.org> X-Mailer: git-send-email 2.42.0 In-Reply-To: <20231029230014.792490-1-sashal@kernel.org> References: <20231029230014.792490-1-sashal@kernel.org> MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore X-stable-base: Linux 5.10.199 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