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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id A43ACC433FE for ; Mon, 31 Jan 2022 11:35:28 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S244845AbiAaLfZ (ORCPT ); Mon, 31 Jan 2022 06:35:25 -0500 Received: from ams.source.kernel.org ([145.40.68.75]:41558 "EHLO ams.source.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1377945AbiAaLXe (ORCPT ); Mon, 31 Jan 2022 06:23:34 -0500 Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ams.source.kernel.org (Postfix) with ESMTPS id 410BAB82A75; Mon, 31 Jan 2022 11:23:33 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 645CAC340E8; Mon, 31 Jan 2022 11:23:31 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1643628212; bh=d4NMCRYFez7Dv/xaGO0VoOIytB742aa78WOrxB63pdc=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=yxhw+/VFjmrn+Nikg+LkKXTBuN67skWNCqBz3pxDR+0xzjbPjxvCpHkEcNgnAOYcD +YXPdlULN7IPAgNI7Dk/m/TIcCXZUr7sgMPpRrjNSUyQO/NypBPNT44+mv/f/v3uGb xGbH7ai2YKDnLy+P6np8ka37JlEv/o0zBBOgtFec= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Dan Carpenter , Guenter Roeck , Sasha Levin Subject: [PATCH 5.16 159/200] hwmon: (adt7470) Prevent divide by zero in adt7470_fan_write() Date: Mon, 31 Jan 2022 11:57:02 +0100 Message-Id: <20220131105238.901810839@linuxfoundation.org> X-Mailer: git-send-email 2.35.1 In-Reply-To: <20220131105233.561926043@linuxfoundation.org> References: <20220131105233.561926043@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Dan Carpenter [ Upstream commit c1ec0cabc36718efc7fe8b4157d41b82d08ec1d2 ] The "val" variable is controlled by the user and comes from hwmon_attr_store(). The FAN_RPM_TO_PERIOD() macro divides by "val" so a zero will crash the system. Check for that and return -EINVAL. Negatives are also invalid so return -EINVAL for those too. Fixes: fc958a61ff6d ("hwmon: (adt7470) Convert to devm_hwmon_device_register_with_info API") Signed-off-by: Dan Carpenter Signed-off-by: Guenter Roeck Signed-off-by: Sasha Levin --- drivers/hwmon/adt7470.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/drivers/hwmon/adt7470.c b/drivers/hwmon/adt7470.c index d519aca4a9d64..fb6d14d213a18 100644 --- a/drivers/hwmon/adt7470.c +++ b/drivers/hwmon/adt7470.c @@ -662,6 +662,9 @@ static int adt7470_fan_write(struct device *dev, u32 attr, int channel, long val struct adt7470_data *data = dev_get_drvdata(dev); int err; + if (val <= 0) + return -EINVAL; + val = FAN_RPM_TO_PERIOD(val); val = clamp_val(val, 1, 65534); -- 2.34.1