From: Dan Williams <dan.j.williams@intel.com>
Date: Tue, 26 Sep 2017 18:21:24 +0000 (-0700)
Subject: libnvdimm, namespace: make 'resource' attribute only readable by root
X-Git-Tag: v4.15-rc1~71^2~21
X-Git-Url: https://asedeno.scripts.mit.edu/gitweb/?a=commitdiff_plain;h=c1fb3542074fd0c4d901d778bd52455111e4eb6f;p=linux.git

libnvdimm, namespace: make 'resource' attribute only readable by root

For the same reason that /proc/iomem returns 0's for non-root readers
and acpi tables are root-only, make the 'resource' attribute for
namespace devices only readable by root. Otherwise we disclose physical
address information.

Fixes: bf9bccc14c05 ("libnvdimm: pmem label sets and namespace instantiation")
Cc: <stable@vger.kernel.org>
Reported-by: Dave Hansen <dave.hansen@linux.intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
---

diff --git a/drivers/nvdimm/namespace_devs.c b/drivers/nvdimm/namespace_devs.c
index 3e4d1e7998da..0af988739a06 100644
--- a/drivers/nvdimm/namespace_devs.c
+++ b/drivers/nvdimm/namespace_devs.c
@@ -1620,7 +1620,7 @@ static umode_t namespace_visible(struct kobject *kobj,
 	if (a == &dev_attr_resource.attr) {
 		if (is_namespace_blk(dev))
 			return 0;
-		return a->mode;
+		return 0400;
 	}
 
 	if (is_namespace_pmem(dev) || is_namespace_blk(dev)) {