From: Dan Williams <dan.j.williams@intel.com>
Date: Fri, 8 Apr 2016 02:59:27 +0000 (-0700)
Subject: libnvdimm, pfn: fix uuid validation
X-Git-Tag: v4.5.2~108
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=90ad05df5acc44fda7c8c315fdf9d758791ed376;p=thirdparty%2Fkernel%2Fstable.git

libnvdimm, pfn: fix uuid validation

commit e5670563f588ed1c0603819350c0f02cec23f5c5 upstream.

If we detect a namespace has a stale info block in the init path, we
should overwrite with the latest configuration.  In fact, we already
return -ENODEV when the parent uuid is invalid, the same should be done
for the 'self' uuid.  Otherwise we can get into a condition where
userspace is unable to reconfigure the pfn-device without directly /
manually invalidating the info block.

Reported-by: Jeff Moyer <jmoyer@redhat.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---

diff --git a/drivers/nvdimm/pfn_devs.c b/drivers/nvdimm/pfn_devs.c
index ae81a2f1da50b..f0b56b3aac4d6 100644
--- a/drivers/nvdimm/pfn_devs.c
+++ b/drivers/nvdimm/pfn_devs.c
@@ -315,7 +315,7 @@ int nd_pfn_validate(struct nd_pfn *nd_pfn)
 	} else {
 		/* from init we validate */
 		if (memcmp(nd_pfn->uuid, pfn_sb->uuid, 16) != 0)
-			return -EINVAL;
+			return -ENODEV;
 	}
 
 	if (nd_pfn->align > nvdimm_namespace_capacity(ndns)) {