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Thu, 2 Feb 2023 14:20:26 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 83694C433EF; Thu, 2 Feb 2023 14:20:25 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1675347626; bh=rjlTumiEDosDf3VoaNyjrPYahbG/tYcj2ovz/+QCuKE=; h=From:To:Cc:Subject:Date:From; b=rjM27dZLm9HA3HJZC6HsZUCqtjXY0zcHHm3bC/m3aQeX55ynmjzNkB6H3m3MSj0Tu mjM8RM4/mSLc9uMImlmdmaFXB96F1YWHkAKNco8snQq2m6OXbqdVade/yiYh0wbwjV 2hDkVBHlm9PilA0HcUkUjM8kqdjdjYWSdEmYVrB0= From: Greg Kroah-Hartman To: linux-mm@kvack.org Cc: Greg Kroah-Hartman , Christoph Lameter , Pekka Enberg , David Rientjes , Joonsoo Kim , Andrew Morton , Vlastimil Babka , Roman Gushchin , Hyeonggon Yoo <42.hyeyoo@gmail.com>, linux-kernel@vger.kernel.org Subject: [PATCH] mm/slub: fix memory leak with using debugfs_lookup() Date: Thu, 2 Feb 2023 15:20:22 +0100 Message-Id: <20230202142022.2300096-1-gregkh@linuxfoundation.org> X-Mailer: git-send-email 2.39.1 MIME-Version: 1.0 X-Developer-Signature: v=1; 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To make things simpler, just call debugfs_lookup_and_remove() instead which handles all of the logic at once. Cc: Christoph Lameter Cc: Pekka Enberg Cc: David Rientjes Cc: Joonsoo Kim Cc: Andrew Morton Cc: Vlastimil Babka Cc: Roman Gushchin Cc: Hyeonggon Yoo <42.hyeyoo@gmail.com> Cc: linux-mm@kvack.org Cc: linux-kernel@vger.kernel.org Signed-off-by: Greg Kroah-Hartman Reviewed-by: Hyeonggon Yoo <42.hyeyoo@gmail.com> Acked-by: Roman Gushchin Acked-by: David Rientjes --- mm/slub.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/mm/slub.c b/mm/slub.c index 13459c69095a..4880e461fcc5 100644 --- a/mm/slub.c +++ b/mm/slub.c @@ -6449,7 +6449,7 @@ static void debugfs_slab_add(struct kmem_cache *s) void debugfs_slab_release(struct kmem_cache *s) { - debugfs_remove_recursive(debugfs_lookup(s->name, slab_debugfs_root)); + debugfs_lookup_and_remove(s->name, slab_debugfs_root); } static int __init slab_debugfs_init(void)