From patchwork Thu Jan 4 11:56:32 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Ying Hsu X-Patchwork-Id: 759925 Received: from mail-pg1-f180.google.com (mail-pg1-f180.google.com [209.85.215.180]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id E47B22135B for ; Thu, 4 Jan 2024 11:57:13 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=chromium.org Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=chromium.org Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=chromium.org header.i=@chromium.org header.b="DsunAFqk" Received: by mail-pg1-f180.google.com with SMTP id 41be03b00d2f7-5ce10b5ee01so255468a12.1 for ; Thu, 04 Jan 2024 03:57:13 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=chromium.org; s=google; t=1704369433; x=1704974233; darn=vger.kernel.org; h=content-transfer-encoding:mime-version:message-id:date:subject:cc :to:from:from:to:cc:subject:date:message-id:reply-to; bh=AaeihiujCSNV/IpYyiqh1GWzfHkk93j+fBxfYGSZUOs=; b=DsunAFqkdVuIlLhHUHLGKF2imFxqdZhNXhfkQ57iaq+AFbsPjHVdoWq3TtB0YhOTVG 6PFVEqjvtzF3DrDVjTrVduIem5q3cesAEgb9yBXlaHDnUWLsHleu6wlKXEc+tjykIgZg 9DKFp3LQ/M+HiMrGZ0ISK56z1K2mOD4MfRKV4= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1704369433; x=1704974233; h=content-transfer-encoding:mime-version:message-id:date:subject:cc :to:from:x-gm-message-state:from:to:cc:subject:date:message-id :reply-to; bh=AaeihiujCSNV/IpYyiqh1GWzfHkk93j+fBxfYGSZUOs=; b=UDzeN3DXz23ktIz4xJu+uU/9kIFPv/SLOoQdJrVVaFE74FztGV0P7GsCn6v77xrUND bzme3EvxGYk+/q+K+IIsvfFByYIHn5/BO4QvzVq8jIECIL5RctxRgE3qIihegOeM6pnQ dotLfesmWBwwIqf6sM2yWd57sHrL+Y3HPYG+Tg4Ubn9o+ni4M3gmDrh3k3OvAXRnd9ks gupyVFZhWEXurGf37KaShAD3PMFyPeJRSHVVTu36mKDUEvaEZTFFVQ8KxSxcMvWVnPRN 80utCaZu5hokc4KYBbuhRrhrWCaSNxLHQhQXGgTyA5SWNRoPVCXVF6Fx8zefyWzgVnGo tGJg== X-Gm-Message-State: AOJu0YwW4Fmbu/UjiSeUJXuuqU627iMKxzl099WCA76IX7LoVglhHPWR BgkWLgSNYTBhpbykOm62UIvWp9cRCaZSwOE2h341RG3U1A== X-Google-Smtp-Source: AGHT+IHXkr/lgGawhP6uKQwmf9t+Yv57Xaq8+wG8HiAtDS/7poRekELI+OR7MUJW3fS+iC7hR4Rn2g== X-Received: by 2002:a05:6a20:be1f:b0:197:33ea:f45 with SMTP id ge31-20020a056a20be1f00b0019733ea0f45mr423598pzb.60.1704369432702; Thu, 04 Jan 2024 03:57:12 -0800 (PST) Received: from localhost (231.137.80.34.bc.googleusercontent.com. [34.80.137.231]) by smtp.gmail.com with UTF8SMTPSA id fn1-20020a056a002fc100b006d9a0902934sm20668062pfb.70.2024.01.04.03.57.11 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Thu, 04 Jan 2024 03:57:12 -0800 (PST) From: Ying Hsu To: linux-bluetooth@vger.kernel.org Cc: luiz.dentz@gmail.com, linux-kernel@vger.kernel.org, chromeos-bluetooth-upstreaming@chromium.org, Ying Hsu Subject: [PATCH] Bluetooth: Avoid potential use-after-free in hci_error_reset Date: Thu, 4 Jan 2024 11:56:32 +0000 Message-ID: <20240104115453.1.Iaa08c695d3dcf819910ea723c3eb502935638172@changeid> X-Mailer: git-send-email 2.43.0.472.g3155946c3a-goog Precedence: bulk X-Mailing-List: linux-bluetooth@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 While handling the HCI_EV_HARDWARE_ERROR event, if the underlying BT controller is not responding, the GPIO reset mechanism would free the hci_dev and lead to a use-after-free in hci_error_reset. Here's the call trace observed on a ChromeOS device with Intel AX201: queue_work_on+0x3e/0x6c __hci_cmd_sync_sk+0x2ee/0x4c0 [bluetooth ] ? init_wait_entry+0x31/0x31 __hci_cmd_sync+0x16/0x20 [bluetooth ] hci_error_reset+0x4f/0xa4 [bluetooth ] process_one_work+0x1d8/0x33f worker_thread+0x21b/0x373 kthread+0x13a/0x152 ? pr_cont_work+0x54/0x54 ? kthread_blkcg+0x31/0x31 ret_from_fork+0x1f/0x30 This patch holds the reference count on the hci_dev while processing a HCI_EV_HARDWARE_ERROR event to avoid potential crash. Signed-off-by: Ying Hsu --- Tested this commit on a chromebook with Intel BT controller. net/bluetooth/hci_core.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/net/bluetooth/hci_core.c b/net/bluetooth/hci_core.c index 65601aa52e0d..a42417926028 100644 --- a/net/bluetooth/hci_core.c +++ b/net/bluetooth/hci_core.c @@ -1049,6 +1049,7 @@ static void hci_error_reset(struct work_struct *work) { struct hci_dev *hdev = container_of(work, struct hci_dev, error_reset); + hci_dev_hold(hdev); BT_DBG("%s", hdev->name); if (hdev->hw_error) @@ -1060,6 +1061,7 @@ static void hci_error_reset(struct work_struct *work) return; hci_dev_do_open(hdev); + hci_dev_put(hdev); } void hci_uuids_clear(struct hci_dev *hdev)