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From:   Yaxiong Tian <iambestgod@outlook.com>
To:     michael.jamet@intel.com, gregkh@linuxfoundation.org,
        andreas.noever@gmail.com, mika.westerberg@linux.intel.com,
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Cc:     tianyaxiong@kylinos.cn, linux-usb@vger.kernel.org,
        linux-kernel@vger.kernel.org
Subject: [PATCH] thunderbolt:debugfs:Fix memory leak with using debugfs_lookup()
Date:   Wed, 22 Nov 2023 16:02:43 +0800
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From: Yaxiong Tian <tianyaxiong@kylinos.cn>

As Greg said,When calling debugfs_lookup() the result must have dput()
called on it,otherwise the memory will leak over time.
So just call debugfs_lookup_and_remove() instead.

Fixes: d0f1e0c2a699 ("thunderbolt: Add support for receiver lane margining")
Signed-off-by: Yaxiong Tian <tianyaxiong@kylinos.cn>
---
 drivers/thunderbolt/debugfs.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/thunderbolt/debugfs.c b/drivers/thunderbolt/debugfs.c
index c9ddd49138d8..e324cd899719 100644
--- a/drivers/thunderbolt/debugfs.c
+++ b/drivers/thunderbolt/debugfs.c
@@ -959,7 +959,7 @@ static void margining_port_remove(struct tb_port *port)
 	snprintf(dir_name, sizeof(dir_name), "port%d", port->port);
 	parent = debugfs_lookup(dir_name, port->sw->debugfs_dir);
 	if (parent)
-		debugfs_remove_recursive(debugfs_lookup("margining", parent));
+		debugfs_lookup_and_remove("margining", parent);
 
 	kfree(port->usb4->margining);
 	port->usb4->margining = NULL;
-- 
2.25.1