From: Chengguang Xu <cgxu519@icloud.com>
Date: Wed, 7 Feb 2018 10:27:06 +0800
Subject: ceph: keep consistent semantic in fscache related option combination
Git-commit: 7ae7a828d9ac249b175f1b6d1c21c77720cd6098
Patch-mainline: v4.17-rc1
References: bsc#1089115

When specifying multiple fscache related options, the result isn't always
the same as option order, this fix will keep strict consistent meaning
by order.

Signed-off-by: Chengguang Xu <cgxu519@icloud.com>
Reviewed-by: "Yan, Zheng" <zyan@redhat.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Acked-by: Luis Henriques <lhenriques@suse.com>
---
 fs/ceph/super.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/fs/ceph/super.c b/fs/ceph/super.c
index fb32379cd42c..ca8a830c07ad 100644
--- a/fs/ceph/super.c
+++ b/fs/ceph/super.c
@@ -314,9 +314,13 @@ static int parse_fsopt_token(char *c, void *private)
 		break;
 	case Opt_fscache:
 		fsopt->flags |= CEPH_MOUNT_OPT_FSCACHE;
+		kfree(fsopt->fscache_uniq);
+		fsopt->fscache_uniq = NULL;
 		break;
 	case Opt_nofscache:
 		fsopt->flags &= ~CEPH_MOUNT_OPT_FSCACHE;
+		kfree(fsopt->fscache_uniq);
+		fsopt->fscache_uniq = NULL;
 		break;
 	case Opt_poolperm:
 		fsopt->flags &= ~CEPH_MOUNT_OPT_NOPOOLPERM;