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 X-Spam-Level: X-Spam-Status: No, score=-9.1 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 62FB7C282D7 for ; Tue, 5 Feb 2019 16:01:28 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 32D002080F for ; Tue, 5 Feb 2019 16:01:28 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="b8INj1l5" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729905AbfBEQBW (ORCPT ); Tue, 5 Feb 2019 11:01:22 -0500 Received: from mail-it1-f193.google.com ([209.85.166.193]:54808 "EHLO mail-it1-f193.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727397AbfBEQBW (ORCPT ); Tue, 5 Feb 2019 11:01:22 -0500 Received: by mail-it1-f193.google.com with SMTP id i145so9560476ita.4; Tue, 05 Feb 2019 08:01:22 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=from:to:cc:subject:date:message-id; bh=0gC8NlSJs+7zlaU+/3qAU9IlYl1p9D7dYB3zpo1O8G0=; b=b8INj1l5QFr3kZhOux9Wf41c3PcoHpBVhbET1R+T6GBPMtc21WUHhyoNofOtjG7drd QGs9qUH4oN8epgY41bhbPueXHuHn14d79P8C0a4MNmKQDut2t5GUcLs5VBkfLqhUztJ9 5NesVDuhLna5uY0h3DmZybiVaGccE/r3VpNc5Y7XnyvW8mhZt0WRS2jbA6XYus6GUsDn RsHNgQqx3vDwaH5uNVzUCg731PClkhmrYvPam0Fq1z4Y0h6I/f8S5xwR9vrOGTaYK3yU proeNOQ1mNyx8lmUVvNTRO91gpj2JIEaBTc6YQw+N8ZFz9ZEiLJAC9Q/7dUeOrXKIEbM ykxw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id; bh=0gC8NlSJs+7zlaU+/3qAU9IlYl1p9D7dYB3zpo1O8G0=; b=OhDCEsnwVRIA3MVYtPPQ7bjSxEwyMTtO8mzi32nv+FhyCDgwxnGhs3ANOJnX0sXaaX sgf8EvKUfwqVmXe+Slwds92/SwnzLbwV/FWsSbowGPJsaRervu3mqJ12V56+U9t5h0gh EfgV2+M4RiBkL2O+phYyhtvajHPBwlvIQfoAecuS0yDrEplHqgX22rHHVOHkmEgomq4o p80pxeVfqsOLsvNkYCbYGJAOZx37vhA7ATvf/Trd56pMhKpimkwYlyN3xIyuNrr3BU4r CC3v40R3md5a+FUinNeqNONk1CsZgZCUGE8iO1Rxqz0FXqR9QZ9xbMSWSIlL7rjFt5jv Ju7g== X-Gm-Message-State: AHQUAuaxSTlOMyc+s+7/6JLm5Us8TqDdc22j11uAgeTohyIGtvqlqjho JTNIsbvdVelR27zUzQWicfA= X-Google-Smtp-Source: AHgI3Ib1lUeNWKlvEVKZHoqbNvPK2K2H+F773Y7uya2XV28rQscuMrxUmcmCpfpPfQX9f+Q1YIq1IA== X-Received: by 2002:a02:6:: with SMTP id 6mr2910857jaa.19.1549382481635; Tue, 05 Feb 2019 08:01:21 -0800 (PST) Received: from svens-asus.arcx.com ([184.94.50.30]) by smtp.gmail.com with ESMTPSA id a79sm1887447ita.11.2019.02.05.08.01.20 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Tue, 05 Feb 2019 08:01:20 -0800 (PST) From: Sven Van Asbroeck X-Google-Original-From: Sven Van Asbroeck To: Samuel Ortiz Cc: linux-wireless@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [RFC v1] NFC: port100: prevent use-after-free on disconnect Date: Tue, 5 Feb 2019 11:01:18 -0500 Message-Id: <20190205160118.27491-1-TheSven73@googlemail.com> X-Mailer: git-send-email 2.17.1 Sender: linux-wireless-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-wireless@vger.kernel.org Problem: The cmd_complete_work work could potentially run after resources are freed in disconnect(). This could cause user-after-free issues. Solution: Reorder disconnect() calls, and explicitly cancel the work using cancel_work_sync(). Signed-off-by: Sven Van Asbroeck --- Samuel, I'm unfamiliar with this driver, and I don't have the h/w, so I cannot test it. This is just a suggestion on how to fix a potential issue. Sven drivers/nfc/port100.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) diff --git a/drivers/nfc/port100.c b/drivers/nfc/port100.c index bb43cebda9dc..66d1bda9208c 100644 --- a/drivers/nfc/port100.c +++ b/drivers/nfc/port100.c @@ -1630,19 +1630,19 @@ static void port100_disconnect(struct usb_interface *interface) struct port100 *dev; dev = usb_get_intfdata(interface); - usb_set_intfdata(interface, NULL); nfc_digital_unregister_device(dev->nfc_digital_dev); - nfc_digital_free_device(dev->nfc_digital_dev); - usb_kill_urb(dev->in_urb); usb_kill_urb(dev->out_urb); + cancel_work_sync(&dev->cmd_complete_work); + usb_free_urb(dev->in_urb); usb_free_urb(dev->out_urb); usb_put_dev(dev->udev); - + nfc_digital_free_device(dev->nfc_digital_dev); kfree(dev->cmd); + usb_set_intfdata(interface, NULL); nfc_info(&interface->dev, "Sony Port-100 NFC device disconnected\n"); } -- 2.17.1