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From:   Xin Hao <xhao@linux.alibaba.com>
To:     cl@linux.com
Cc:     penberg@kernel.org, rientjes@google.com, iamjoonsoo.kim@lge.com,
        akpm@linux-foundation.org, vbabka@suse.cz,
        roman.gushchin@linux.dev, linux-mm@kvack.org,
        linux-kernel@vger.kernel.org
Subject: [PATCH] mm/slub: release kobject if kobject_init_and_add failed in sysfs_slab_add
Date:   Thu, 11 Aug 2022 10:52:58 +0800
Message-Id: <20220811025258.68684-1-xhao@linux.alibaba.com>
MIME-Version: 1.0
Content-Transfer-Encoding: 8bit
Precedence: bulk

In kobject_init_and_add() function, the refcount is setted by calling
kobject_init() function, regardless of whether the return value is zero
or not, therefore, we must call kobject_del(&s->kobj) to prevent memory
of s->kobj is leaked.

Signed-off-by: Xin Hao <xhao@linux.alibaba.com>
---
 mm/slub.c | 7 +++----
 1 file changed, 3 insertions(+), 4 deletions(-)

diff --git a/mm/slub.c b/mm/slub.c
index b1281b8654bd..63b0a8a3a71f 100644
--- a/mm/slub.c
+++ b/mm/slub.c
@@ -5981,19 +5981,18 @@ static int sysfs_slab_add(struct kmem_cache *s)
 
 	err = sysfs_create_group(&s->kobj, &slab_attr_group);
 	if (err)
-		goto out_del_kobj;
+		goto out;
 
 	if (!unmergeable) {
 		/* Setup first alias */
 		sysfs_slab_alias(s, s->name);
 	}
+	return err;
 out:
 	if (!unmergeable)
 		kfree(name);
-	return err;
-out_del_kobj:
 	kobject_del(&s->kobj);
-	goto out;
+	return err;
 }
 
 void sysfs_slab_unlink(struct kmem_cache *s)
-- 
2.31.0