From patchwork Sat Sep 1 08:25:08 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jia-Ju Bai X-Patchwork-Id: 10584645 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 6EEAC5A4 for ; Sat, 1 Sep 2018 08:25:19 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 5DC742AF2C for ; Sat, 1 Sep 2018 08:25:19 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 513DF2AF48; Sat, 1 Sep 2018 08:25:19 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-8.0 required=2.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FROM,MAILING_LIST_MULTI,RCVD_IN_DNSWL_HI autolearn=ham version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id E3D142AF2C for ; Sat, 1 Sep 2018 08:25:18 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727261AbeIAMga (ORCPT ); Sat, 1 Sep 2018 08:36:30 -0400 Received: from mail-pl1-f194.google.com ([209.85.214.194]:33978 "EHLO mail-pl1-f194.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725973AbeIAMg3 (ORCPT ); Sat, 1 Sep 2018 08:36:29 -0400 Received: by mail-pl1-f194.google.com with SMTP id f6-v6so6495625plo.1; Sat, 01 Sep 2018 01:25:17 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=from:to:cc:subject:date:message-id; bh=sXqnVArd76Zgg0unGNLqHjvcOP53ZMNezD1eJsDUFA0=; b=ZZvLudJ4H57cdY/Uo2XUCN1vdke2mcsthqQV/+qFeH8ow/k4a813p3xSV2VQehYHtn NijB5roo0qhnqqqhbT9Ic06PjVIDSdaIwEEdZkQ9xd78/YjIEdO1puWavjl80U7FCtP0 QPROKBoqsIwsRqY6KQedqDCEmodICzzBHSZbk3gywAbHXREpV/oV6pBueadUCNtJoeYD 5FtoAihqhhx5JtPc4WqkGPyKxoOym/QFvgQX8/Yr0/nt8YfeOnGybsLor76zm/iHo178 3JFUku0QgMsIOhftbFW3bzoNlJzNSFirxBb2gOUjLExVcVQkeO1vQDBCO/hrSekn3M0g mONA== 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=sXqnVArd76Zgg0unGNLqHjvcOP53ZMNezD1eJsDUFA0=; b=jG8BVwD2cD8HsVIpUli6/mKuWUP21jprCslkEDmh3Q9KKeUFGUyaYxazb3i1YxJVCk ZvBjnkFNKuGR0A/ckwSEZ8cWW9iDqSuivo7aw/dpTQCc+QzyqqpHIZoyVbKT+sz3buGA mbEKPHyHP5ooJ2mjfM1AR7BVFav60F0orfco6EjB5khGhYdzwWdf2jfhK5pFoEglXnNZ z3TDvCuv5N8y6adiTJF6kQ/kF6rFlgqReOE+woc1MyOYVysCecBt9xTAmEHHuaBYzoeZ nXRF/UDLaGxp8qZ0NqcwvNqs3MIhXVBHlW9paCLFiNydgnG1rVJGeyjhNvUaQbWLaMJY fnAQ== X-Gm-Message-State: APzg51AqQrDO8taYTl7v3tdDVzWpBx/iYbgrrHNBwIJaGGF75XwBReD5 4et/c8a7U2gXGcHKrh9VNHg= X-Google-Smtp-Source: ANB0VdYi7EqNjHqFqKoHX5Nv1Ttrpy97qMD4JnOAnbuN1VjTys4FPUm3umObWElbChn+sI6nlAKeyw== X-Received: by 2002:a17:902:4124:: with SMTP id e33-v6mr19261558pld.48.1535790317609; Sat, 01 Sep 2018 01:25:17 -0700 (PDT) Received: from localhost.localdomain ([2402:f000:1:4414:4130:91db:5d72:621b]) by smtp.gmail.com with ESMTPSA id y69-v6sm22891422pfd.36.2018.09.01.01.25.15 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Sat, 01 Sep 2018 01:25:17 -0700 (PDT) From: Jia-Ju Bai To: gregkh@linuxfoundation.org, daniel@gimpelevich.san-francisco.ca.us, felipe.balbi@linux.intel.com, johan@kernel.org Cc: linux-usb@vger.kernel.org, linux-kernel@vger.kernel.org, Jia-Ju Bai Subject: [PATCH] usb: misc: uss720: Fix two sleep-in-atomic-context bugs Date: Sat, 1 Sep 2018 16:25:08 +0800 Message-Id: <20180901082508.16995-1-baijiaju1990@gmail.com> X-Mailer: git-send-email 2.17.0 Sender: linux-usb-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-usb@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP async_complete() in uss720.c is a completion handler function for the USB driver. So it should not sleep, but it is can sleep according to the function call paths (from bottom to top) in Linux-4.16. [FUNC] set_1284_register(GFP_KERNEL) drivers/usb/misc/uss720.c, 372: set_1284_register in parport_uss720_frob_control drivers/parport/ieee1284.c, 560: [FUNC_PTR]parport_uss720_frob_control in parport_ieee1284_ack_data_avail drivers/parport/ieee1284.c, 577: parport_ieee1284_ack_data_avail in parport_ieee1284_interrupt ./include/linux/parport.h, 474: parport_ieee1284_interrupt in parport_generic_irq drivers/usb/misc/uss720.c, 116: parport_generic_irq in async_complete [FUNC] get_1284_register(GFP_KERNEL) drivers/usb/misc/uss720.c, 382: get_1284_register in parport_uss720_read_status drivers/parport/ieee1284.c, 555: [FUNC_PTR]parport_uss720_read_status in parport_ieee1284_ack_data_avail drivers/parport/ieee1284.c, 577: parport_ieee1284_ack_data_avail in parport_ieee1284_interrupt ./include/linux/parport.h, 474: parport_ieee1284_interrupt in parport_generic_irq drivers/usb/misc/uss720.c, 116: parport_generic_irq in async_complete Note that [FUNC_PTR] means a function pointer call is used. To fix these bugs, GFP_KERNEL is replaced with GFP_ATOMIC. These bugs are found by my static analysis tool DSAC. Signed-off-by: Jia-Ju Bai --- drivers/usb/misc/uss720.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/usb/misc/uss720.c b/drivers/usb/misc/uss720.c index de9a502491c2..69822852888a 100644 --- a/drivers/usb/misc/uss720.c +++ b/drivers/usb/misc/uss720.c @@ -369,7 +369,7 @@ static unsigned char parport_uss720_frob_control(struct parport *pp, unsigned ch mask &= 0x0f; val &= 0x0f; d = (priv->reg[1] & (~mask)) ^ val; - if (set_1284_register(pp, 2, d, GFP_KERNEL)) + if (set_1284_register(pp, 2, d, GFP_ATOMIC)) return 0; priv->reg[1] = d; return d & 0xf; @@ -379,7 +379,7 @@ static unsigned char parport_uss720_read_status(struct parport *pp) { unsigned char ret; - if (get_1284_register(pp, 1, &ret, GFP_KERNEL)) + if (get_1284_register(pp, 1, &ret, GFP_ATOMIC)) return 0; return ret & 0xf8; }