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=-9.9 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,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 EA3A9C4360C for ; Fri, 4 Oct 2019 14:26:19 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id BEB2021D81 for ; Fri, 4 Oct 2019 14:26:19 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=chromium.org header.i=@chromium.org header.b="ky6yHwsm" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731030AbfJDO0S (ORCPT ); Fri, 4 Oct 2019 10:26:18 -0400 Received: from mail-io1-f66.google.com ([209.85.166.66]:43005 "EHLO mail-io1-f66.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730803AbfJDO0R (ORCPT ); Fri, 4 Oct 2019 10:26:17 -0400 Received: by mail-io1-f66.google.com with SMTP id n197so13879325iod.9 for ; Fri, 04 Oct 2019 07:26:17 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=chromium.org; s=google; h=from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=2bQyhaQUr8TvOSgV5QjfNzwDgjUaiOuNFWU91AgXyWA=; b=ky6yHwsmLad6oYcifbJnyYwi8x8dg05hUkc7KgOHwOY6muINbt53lNl3IPP1KLIQNH g81LxwTrAToPheSYCWkHZk79aT7a+JNFLaEuyQfzX3bxw65IDLdifs/nx7xI/wEwn5sy 5rWeH4FAzVk9mircHyal717eMoMGTEw+0ib1U= 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:mime-version :content-transfer-encoding; bh=2bQyhaQUr8TvOSgV5QjfNzwDgjUaiOuNFWU91AgXyWA=; b=mmE7ZnMTDCcFMh7CU9RUi0TcuYSOHKuk4JXon4oV+0Vm2MCTX2OTHMtozJ5pxemK7G eKuGE8MNvpQ3WD7QMT/U53cim5B+ArCVcWsmB4H7LyUU+DzyaLIGPOmVoSnoGyI7/Ao5 Xk0Z8hIHghA2YTaYZRuRbTLKjLDvWiqfsSbW52Yq1dC76oljXNkHWfw/7ndE6vZQDb+q /OO6QHgs8gT882xCX0tDjAGucAEduCwhY0sHI7SCahNgiOt5BvkmBJ89IhHHGwM/6qPR NQb21G2Dpzt238dlSs2L56wHfuGB7fZp2R7EsPmuQeSrB3gl3moim2g0H5F3UvxQGh1k e3MA== X-Gm-Message-State: APjAAAVaSPjga2MogVZPDTsvXS0Edu0b/XUIgL2CHRADBcHjPPpnsAkP aOU2hNJ9Draaw26LKgqzTGMNdw== X-Google-Smtp-Source: APXvYqxtzAP/55XHsBk7FFZ7dGRUurYxb76/Kg8H3ULp2f/RY39bFYHe97CoJz39nk1we5lAnTIT/A== X-Received: by 2002:a92:9198:: with SMTP id e24mr15795776ill.195.1570199176595; Fri, 04 Oct 2019 07:26:16 -0700 (PDT) Received: from ncrews2.bld.corp.google.com ([2620:15c:183:200:cb43:2cd4:65f5:5c84]) by smtp.gmail.com with ESMTPSA id d6sm2041379iop.34.2019.10.04.07.26.15 (version=TLS1_2 cipher=ECDHE-RSA-AES128-SHA bits=128/128); Fri, 04 Oct 2019 07:26:15 -0700 (PDT) From: Nick Crews To: Alexandre Belloni , Alessandro Zummo Cc: linux-rtc@vger.kernel.org, linux-kernel@vger.kernel.org, Pavel Machek , enric.balletbo@collabora.com, bleung@chromium.org, dlaurie@chromium.org, djkurtz@chromium.org, dtor@google.com, campello@chromium.org, Nick Crews Subject: [PATCH v4] rtc: wilco-ec: Handle reading invalid times Date: Fri, 4 Oct 2019 08:26:08 -0600 Message-Id: <20191004142608.170159-1-ncrews@chromium.org> X-Mailer: git-send-email 2.21.0 MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org If the RTC HW returns an invalid time, the rtc_year_days() call would crash. This patch adds error logging in this situation, and removes the tm_yday and tm_wday calculations. These fields should not be relied upon by userspace according to man rtc, and thus we don't need to calculate them. Signed-off-by: Nick Crews --- drivers/rtc/rtc-wilco-ec.c | 8 +++++--- 1 file changed, 5 insertions(+), 3 deletions(-) diff --git a/drivers/rtc/rtc-wilco-ec.c b/drivers/rtc/rtc-wilco-ec.c index 8ad4c4e6d557..ff46066a68a4 100644 --- a/drivers/rtc/rtc-wilco-ec.c +++ b/drivers/rtc/rtc-wilco-ec.c @@ -110,10 +110,12 @@ static int wilco_ec_rtc_read(struct device *dev, struct rtc_time *tm) tm->tm_mday = rtc.day; tm->tm_mon = rtc.month - 1; tm->tm_year = rtc.year + (rtc.century * 100) - 1900; - tm->tm_yday = rtc_year_days(tm->tm_mday, tm->tm_mon, tm->tm_year); + /* Ignore other tm fields, man rtc says userspace shouldn't use them. */ - /* Don't compute day of week, we don't need it. */ - tm->tm_wday = -1; + if (rtc_valid_tm(tm)) { + dev_err(dev, "Time from RTC is invalid: %ptRr\n", tm); + return -EIO; + } return 0; } -- 2.21.0