Return-Path: Received: from mga17.intel.com (mga17.intel.com [192.55.52.151]) by galois.linutronix.de (Postfix) with ESMTPS id 24DC040D2D for ; Tue, 14 Jul 2020 02:09:36 +0200 (CEST) Date: Mon, 13 Jul 2020 17:03:44 -0700 From: Pawan Gupta Subject: [MODERATED] [PATCH] Raffle 0 Message-ID: =?utf-8?q?=3C747d3dfb86532bf0548a7251515d2a0e989fb5e7=2E159468?= =?utf-8?q?4594=2Egit=2Epawan=2Ekumar=2Egupta=40linux=2Eintel=2Ecom=3E?= MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit To: speck@linutronix.de List-ID: From: Pawan Gupta Subject: [PATCH] powercap: restrict energy meter to root access From: Len Brown Remove non-privileged user access to power data contained in /sys/class/powercap/intel_rapl/*/energy_uj Non-privileged users currently have read access to power data and can use this data to form a security attack. Some privileged drivers/applications need read access to this data but don't expose it to non-privileged users. For example, thermald uses this data to ensure that power management works correctly. Thus removing non-privileged access is preferred over completely disabling this power reporting capability with CONFIG_INTEL_RAPL=n. Fixes: 95677a9a3847 ("PowerCap: Fix mode for energy counter") Signed-off-by: Len Brown --- drivers/powercap/powercap_sys.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/powercap/powercap_sys.c b/drivers/powercap/powercap_sys.c index f808c5fa9838..3f0b8e2ef3d4 100644 --- a/drivers/powercap/powercap_sys.c +++ b/drivers/powercap/powercap_sys.c @@ -367,9 +367,9 @@ static void create_power_zone_common_attributes( &dev_attr_max_energy_range_uj.attr; if (power_zone->ops->get_energy_uj) { if (power_zone->ops->reset_energy_uj) - dev_attr_energy_uj.attr.mode = S_IWUSR | S_IRUGO; + dev_attr_energy_uj.attr.mode = S_IWUSR | S_IRUSR; else - dev_attr_energy_uj.attr.mode = S_IRUGO; + dev_attr_energy_uj.attr.mode = S_IRUSR; power_zone->zone_dev_attrs[count++] = &dev_attr_energy_uj.attr; } -- 2.21.3