From patchwork Fri Jul 22 10:23:30 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Archie Pusaka X-Patchwork-Id: 12926234 X-Patchwork-Delegate: kuba@kernel.org 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 39410C433EF for ; Fri, 22 Jul 2022 10:23:43 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234467AbiGVKXl (ORCPT ); Fri, 22 Jul 2022 06:23:41 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:56712 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234443AbiGVKXj (ORCPT ); Fri, 22 Jul 2022 06:23:39 -0400 Received: from mail-pg1-x549.google.com (mail-pg1-x549.google.com [IPv6:2607:f8b0:4864:20::549]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id AECA78E4D0 for ; Fri, 22 Jul 2022 03:23:38 -0700 (PDT) Received: by mail-pg1-x549.google.com with SMTP id x17-20020a631711000000b0041240801d34so2222040pgl.17 for ; Fri, 22 Jul 2022 03:23:38 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20210112; h=date:message-id:mime-version:subject:from:to:cc; bh=hBY0IJGvt2jUk2Z9CmQ7C6mkhe5vlF82u2blKwho5Mw=; b=KibTanT7hOnEd+7E4Vg8YmsyhYwS2LYcPHC595oEHzyTeOsx9D/IvnI1qfQ4dKui0z 68cdSTR2hWoGbXfwHzZzwcxy7K6G87aRWlHR89SX15NeBH4oCgKd5nLz3VSLXXad1xdR SVIQEbIhp4u3jrpwoIfq80J1RSb4nC/5A+jrfIhQ1MjIldWmx28U7LHMg2ktroWgMnK5 iiFjDSNCAl6rjjXAiYG594fy6I/jy2t/w+a4qb8AeMW9+rEyZBKx7KOXUJipMdJg9Vcx yF3/oANduwV1UvIctvAtBPDRrU0NXLoBa6kGuBZK+9umy0hottJBhlPPivg81qwfhrJr v6Pg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:date:message-id:mime-version:subject:from:to:cc; bh=hBY0IJGvt2jUk2Z9CmQ7C6mkhe5vlF82u2blKwho5Mw=; b=x1UQGS9Qp5OtKc+1Yx8T4hSUv/qObom1zXmeexhV1wYnmqkWYDaEpoWZpzp9EUGhxu dltxDo3Hjy+4H72OsNUYPtr3hNLaxQwsHIHv0G7fBKom+FWHFH9frTiJQkGeoMFeD+ir 5EqS2z5XLPoFN/L9EtV3JLJMM7rhOZSZohIcCDak+0Qw3kigHrMiIVXagqeu+x1gSU4A oRKzAOugcuc15bHy0AuGJXGA7eV9tfpydi8gzbUhat2wvWiaoXyjXioK5VWGGKJRX4d1 4x6uc3piDODkrXJ5/uqfvXBdjrFrSTwji7g3pC/BHWi1+dn1SbXie9daIbFfrn0FVAsx FZdg== X-Gm-Message-State: AJIora/UPdj0qV8CF8egqJOC1upbXQTRfJe2q2qPzU26FrqxhGcnSJUf iQHJkAxkueOxgq1xw8dU32LKRhcrPfUD X-Google-Smtp-Source: AGRyM1usGPR5zIG3GM+0W7vlI1ncHH6VPG7LalUXm1vbL88XAZTxlmvluhzpJyRCRTJJ8AYQrXhBEElHFLjM X-Received: from apusaka-p920.tpe.corp.google.com ([2401:fa00:1:17:4ceb:6376:128b:2c25]) (user=apusaka job=sendgmr) by 2002:a05:6a00:1a44:b0:528:6af7:ff4a with SMTP id h4-20020a056a001a4400b005286af7ff4amr2806413pfv.78.1658485418118; Fri, 22 Jul 2022 03:23:38 -0700 (PDT) Date: Fri, 22 Jul 2022 18:23:30 +0800 Message-Id: <20220722182248.1.I20e96c839200bb75cd6af80384f16c8c01498f57@changeid> Mime-Version: 1.0 X-Mailer: git-send-email 2.37.1.359.gd136c6c3e2-goog Subject: [PATCH] Bluetooth: hci_sync: Use safe loop when adding accept list From: Archie Pusaka To: linux-bluetooth , Luiz Augusto von Dentz , Marcel Holtmann Cc: CrosBT Upstreaming , Archie Pusaka , Zhengping Jiang , Michael Sun , "David S. Miller" , Eric Dumazet , Jakub Kicinski , Johan Hedberg , Paolo Abeni , linux-kernel@vger.kernel.org, netdev@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org X-Patchwork-Delegate: kuba@kernel.org From: Archie Pusaka When in the middle of adding accept list, the userspace can still remove devices, therefore causing crash if the removed device is the one being processed. Use a safe loop mechanism to guard against deletion while iterating the pending items. Below is a sample btsnoop log when user enters wrong passkey when pairing a LE keyboard and the corresponding stacktrace. @ MGMT Event: Command Complete (0x0001) plen 10 Add Device (0x0033) plen 7 Status: Success (0x00) LE Address: CA:CA:BD:78:37:F9 (Static) < HCI Command: LE Add Device To Accept List (0x08|0x0011) plen 7 Address type: Random (0x01) Address: CA:CA:BD:78:37:F9 (Static) @ MGMT Event: Device Removed (0x001b) plen 7 LE Address: CA:CA:BD:78:37:F9 (Static) > HCI Event: Command Complete (0x0e) plen 4 LE Add Device To Accept List (0x08|0x0011) ncmd 1 Status: Success (0x00) [ 167.409813] Call trace: [ 167.409983] hci_le_add_accept_list_sync+0x64/0x26c [ 167.410150] hci_update_passive_scan_sync+0x5f0/0x6dc [ 167.410318] add_device_sync+0x18/0x24 [ 167.410486] hci_cmd_sync_work+0xe8/0x150 [ 167.410509] process_one_work+0x140/0x4d0 [ 167.410526] worker_thread+0x134/0x2e4 [ 167.410544] kthread+0x148/0x160 [ 167.410562] ret_from_fork+0x10/0x30 Signed-off-by: Archie Pusaka Reviewed-by: Zhengping Jiang Reviewed-by: Michael Sun --- net/bluetooth/hci_sync.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/net/bluetooth/hci_sync.c b/net/bluetooth/hci_sync.c index 3067d94e7a8e..8e843d34f7de 100644 --- a/net/bluetooth/hci_sync.c +++ b/net/bluetooth/hci_sync.c @@ -1863,7 +1863,7 @@ struct sk_buff *hci_read_local_oob_data_sync(struct hci_dev *hdev, */ static u8 hci_update_accept_list_sync(struct hci_dev *hdev) { - struct hci_conn_params *params; + struct hci_conn_params *params, *tmp; struct bdaddr_list *b, *t; u8 num_entries = 0; bool pend_conn, pend_report; @@ -1930,7 +1930,7 @@ static u8 hci_update_accept_list_sync(struct hci_dev *hdev) * just abort and return filer policy value to not use the * accept list. */ - list_for_each_entry(params, &hdev->pend_le_conns, action) { + list_for_each_entry_safe(params, tmp, &hdev->pend_le_conns, action) { err = hci_le_add_accept_list_sync(hdev, params, &num_entries); if (err) goto done; @@ -1940,7 +1940,7 @@ static u8 hci_update_accept_list_sync(struct hci_dev *hdev) * the list of pending reports and also add these to the * accept list if there is still space. Abort if space runs out. */ - list_for_each_entry(params, &hdev->pend_le_reports, action) { + list_for_each_entry_safe(params, tmp, &hdev->pend_le_reports, action) { err = hci_le_add_accept_list_sync(hdev, params, &num_entries); if (err) goto done;