From patchwork Tue Dec 12 02:50:37 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jia-Ju Bai X-Patchwork-Id: 10106147 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id 247CA602B3 for ; Tue, 12 Dec 2017 02:48:53 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 1767B29945 for ; Tue, 12 Dec 2017 02:48:53 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 0BFB729950; Tue, 12 Dec 2017 02:48:53 +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=-7.0 required=2.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID, DKIM_VALID_AU, FREEMAIL_FROM, RCVD_IN_DNSWL_HI autolearn=unavailable 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 AE67B29945 for ; Tue, 12 Dec 2017 02:48:52 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752375AbdLLCsl (ORCPT ); Mon, 11 Dec 2017 21:48:41 -0500 Received: from m12-17.163.com ([220.181.12.17]:58910 "EHLO m12-17.163.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752134AbdLLCsf (ORCPT ); Mon, 11 Dec 2017 21:48:35 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=163.com; s=s110527; h=From:Subject:Date:Message-Id; bh=0/9cDP+3CAIp6/fLht n5LTmUAg44yHsbSUAoZJiJYqk=; b=M8IDBbik69xLPKIohZMK+h9aXpdkjFdUF2 ykBavVaoKnlu1Lj9yWmmlrhbC5ok3qe5G1VI4SR5VJJ9dbnGDY1QfdotAMZTtXDg 0Yg9ASRIuAl0jBw7wKWz9AJjtSGOyjH9MHFrNjnTi2bTOUli/bTb7DPRNdQYR4Cj UV4bzd1Ag= Received: from bai-oslab.tsinghua.edu.cn (unknown [166.111.70.15]) by smtp13 (Coremail) with SMTP id EcCowABXipRvQy9aa0AhDQ--.62424S2; Tue, 12 Dec 2017 10:48:18 +0800 (CST) From: Jia-Ju Bai To: schmitzmic@gmail.com, fthain@telegraphics.com.au, jejb@linux.vnet.ibm.com, martin.petersen@oracle.com Cc: linux-scsi@vger.kernel.org, linux-kernel@vger.kernel.org, Jia-Ju Bai Subject: [PATCH] NCR5380: Fix a possible sleep-in-atomic bug in NCR5380_poll_politely2 Date: Tue, 12 Dec 2017 10:50:37 +0800 Message-Id: <1513047037-18102-1-git-send-email-baijiaju1990@163.com> X-Mailer: git-send-email 1.7.9.5 X-CM-TRANSID: EcCowABXipRvQy9aa0AhDQ--.62424S2 X-Coremail-Antispam: 1Uf129KBjvJXoWrKFWfJr1DKFykKF1UWryrtFb_yoW8JrW3pr WxWas2vr1DGrW0kw1UAF4UtryYg3WxJ34UGan7C3yDWF4ktFnYkF4SyFyUZFWxXFyrAr1f WFyvyrW7CFs8t3DanT9S1TB71UUUUUUqnTZGkaVYY2UrUUUUjbIjqfuFe4nvWSU5nxnvy2 9KBjDUYxBIdaVFxhVjvjDU0xZFpf9x07jkl1kUUUUU= X-Originating-IP: [166.111.70.15] X-CM-SenderInfo: xedlyx5dmximizq6il2tof0z/1tbiZRKselWBXtrTpgAAsE Sender: linux-scsi-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-scsi@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP From: Jia-Ju Bai The kernel module may sleep under a spinlock. The function call paths are: NCR5380_select (acquire the spinlock) NCR5380_reselect NCR5380_poll_politely NCR5380_poll_politely2 schedule_timeout_uninterruptible --> may sleep NCR5380_abort (acquire the spinlock) do_abort NCR5380_poll_politely NCR5380_poll_politely2 schedule_timeout_uninterruptible --> may sleep To fix it, schedule_timeout_uninterruptible is replaced with mdelay. This bug is found by my static analysis tool(DSAC) and checked by my code review. Signed-off-by: Jia-Ju Bai --- drivers/scsi/NCR5380.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/scsi/NCR5380.c b/drivers/scsi/NCR5380.c index 90ea0f5..4176aca 100644 --- a/drivers/scsi/NCR5380.c +++ b/drivers/scsi/NCR5380.c @@ -202,7 +202,7 @@ static int NCR5380_poll_politely2(struct NCR5380_hostdata *hostdata, /* Repeatedly sleep for 1 ms until deadline */ while (time_is_after_jiffies(deadline)) { - schedule_timeout_uninterruptible(1); + mdelay(1); if ((NCR5380_read(reg1) & bit1) == val1) return 0; if ((NCR5380_read(reg2) & bit2) == val2)