From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 9014730CD89 for ; Wed, 31 Dec 2025 20:41:40 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1767213700; cv=none; b=KPvHIgTpyO0jExzSCxTKFKy9q7p5VO4zNaq6gw6ygIKp5SlqTVWR5RpxbddZarPdOFpY1CnPn5mDlQhKVUqyleuhrZoS/0+aGIjSVD1NTrksMjkcUzJkXJNedjPikuQ6oIOAhLpAOrm0qPKS50h/Rvrun/eLnzoNlb1KMGUyw7E= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1767213700; c=relaxed/simple; bh=R0ow8dD/P8ulOCfIDijOdDNl7DfPUma69rac658ykZI=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=kUtdCtTlIIN9XsVDqbvlfc7xB0DkPs9dIlN7RmfRJpuYOLiO+nYriG9GptdDOpfuU4uz8flrrNRrbrP+Z7hQTafzpSnxMOTT4uqA4uAXS+JULQnWGnTy+uv5iG3WJcse1lySIgpPR2v9DSCwOTI+q5NDl/VrijcJ5MFcgF+Qirg= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=m3wW215g; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="m3wW215g" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 9B75BC19422; Wed, 31 Dec 2025 20:41:39 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1767213700; bh=R0ow8dD/P8ulOCfIDijOdDNl7DfPUma69rac658ykZI=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=m3wW215gNezponODch1x4IyPsWl4qSX/ctwV7jRNpr41SOcuI031RRRw0tMZFOPJQ V9ZPUBLvD4yectd+bNra1NFJHCfLvS3D4M/WMzzgQSp0Fh8EZrVm4ASZWAPTYvefhs i0YpffFXKB3fNrH9h3QcC5Cd9rf9d6UAD4KwT0FTgQ8JNze7cEdVF7eLQBgN/lw1au I5faeQV+5hx6K5u7eXWCQf8xy9ulgBlKY7VZ2sjHJVnLejE6DTuZla1OoWIKJvKr3u hVdF+WvaTsiD2QTgkDyjA95Vz7+fsjEB4B5PVtpc7OYEsGYdOXzDAOUuDYl/VSWeho gMWFGJsDAxgIA== From: Sasha Levin To: stable@vger.kernel.org Cc: Gui-Dong Han , Guenter Roeck , Sasha Levin Subject: [PATCH 5.10.y 2/2] hwmon: (max16065) Use local variable to avoid TOCTOU Date: Wed, 31 Dec 2025 15:41:36 -0500 Message-ID: <20251231204136.3475586-2-sashal@kernel.org> X-Mailer: git-send-email 2.51.0 In-Reply-To: <20251231204136.3475586-1-sashal@kernel.org> References: <2025122905-unstable-smuggling-c1a3@gregkh> <20251231204136.3475586-1-sashal@kernel.org> Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit From: Gui-Dong Han [ Upstream commit b8d5acdcf525f44e521ca4ef51dce4dac403dab4 ] In max16065_current_show, data->curr_sense is read twice: once for the error check and again for the calculation. Since i2c_smbus_read_byte_data returns negative error codes on failure, if the data changes to an error code between the check and the use, ADC_TO_CURR results in an incorrect calculation. Read data->curr_sense into a local variable to ensure consistency. Note that data->curr_gain is constant and safe to access directly. This aligns max16065_current_show with max16065_input_show, which already uses a local variable for the same reason. Link: https://lore.kernel.org/all/CALbr=LYJ_ehtp53HXEVkSpYoub+XYSTU8Rg=o1xxMJ8=5z8B-g@mail.gmail.com/ Fixes: f5bae2642e3d ("hwmon: Driver for MAX16065 System Manager and compatibles") Cc: stable@vger.kernel.org Signed-off-by: Gui-Dong Han Link: https://lore.kernel.org/r/20251128124709.3876-1-hanguidong02@gmail.com Signed-off-by: Guenter Roeck Signed-off-by: Sasha Levin --- drivers/hwmon/max16065.c | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-) diff --git a/drivers/hwmon/max16065.c b/drivers/hwmon/max16065.c index 66d92f705136..5787db933fad 100644 --- a/drivers/hwmon/max16065.c +++ b/drivers/hwmon/max16065.c @@ -216,12 +216,13 @@ static ssize_t max16065_current_show(struct device *dev, struct device_attribute *da, char *buf) { struct max16065_data *data = max16065_update_device(dev); + int curr_sense = data->curr_sense; - if (unlikely(data->curr_sense < 0)) - return data->curr_sense; + if (unlikely(curr_sense < 0)) + return curr_sense; return sysfs_emit(buf, "%d\n", - ADC_TO_CURR(data->curr_sense, data->curr_gain)); + ADC_TO_CURR(curr_sense, data->curr_gain)); } static ssize_t max16065_limit_store(struct device *dev, -- 2.51.0