From: Chao Yu <yuchao0@huawei.com>
Date: Fri, 23 Jun 2017 05:08:22 +0000 (-0400)
Subject: ext4: check return value of kstrtoull correctly in reserved_clusters_store
X-Git-Tag: v4.4.77~3
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=ad5a88c54cd299f3bb2bf53810dd5bb5805369c3;p=thirdparty%2Fkernel%2Fstable.git

ext4: check return value of kstrtoull correctly in reserved_clusters_store

commit 1ea1516fbbab2b30bf98c534ecaacba579a35208 upstream.

kstrtoull returns 0 on success, however, in reserved_clusters_store we
will return -EINVAL if kstrtoull returns 0, it makes us fail to update
reserved_clusters value through sysfs.

Fixes: 76d33bca5581b1dd5c3157fa168db849a784ada4
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Miao Xie <miaoxie@huawei.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---

diff --git a/fs/ext4/sysfs.c b/fs/ext4/sysfs.c
index 5d09ea585840a..c2ee23acf3594 100644
--- a/fs/ext4/sysfs.c
+++ b/fs/ext4/sysfs.c
@@ -100,7 +100,7 @@ static ssize_t reserved_clusters_store(struct ext4_attr *a,
 	int ret;
 
 	ret = kstrtoull(skip_spaces(buf), 0, &val);
-	if (!ret || val >= clusters)
+	if (ret || val >= clusters)
 		return -EINVAL;
 
 	atomic64_set(&sbi->s_resv_clusters, val);