From:   Sasha Levin <sashal@kernel.org>
To:     linux-kernel@vger.kernel.org, stable@vger.kernel.org
Cc:     Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        Jiri Slaby <jirislaby@kernel.org>,
        Sasha Levin <sashal@kernel.org>, linux-serial@vger.kernel.org
Subject: [PATCH AUTOSEL 6.2 50/64] tty: pcn_uart: fix memory leak with using debugfs_lookup()
Date:   Fri,  3 Mar 2023 16:40:52 -0500
Message-Id: <20230303214106.1446460-50-sashal@kernel.org>
In-Reply-To: <20230303214106.1446460-1-sashal@kernel.org>
References: <20230303214106.1446460-1-sashal@kernel.org>
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From: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

[ Upstream commit 04a189c720aa2b6091442113ce9b9bc93552dff8 ]

When calling debugfs_lookup() the result must have dput() called on it,
otherwise the memory will leak over time.  To make things simpler, just
call debugfs_lookup_and_remove() instead which handles all of the logic
at once.

Cc: Jiri Slaby <jirislaby@kernel.org>
Link: https://lore.kernel.org/r/20230202141221.2293012-1-gregkh@linuxfoundation.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/tty/serial/pch_uart.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/tty/serial/pch_uart.c b/drivers/tty/serial/pch_uart.c
index 9576ba8bbc40e..cc83b772b7ca9 100644
--- a/drivers/tty/serial/pch_uart.c
+++ b/drivers/tty/serial/pch_uart.c
@@ -1775,7 +1775,7 @@ static void pch_uart_exit_port(struct eg20t_port *priv)
 	char name[32];
 
 	snprintf(name, sizeof(name), "uart%d_regs", priv->port.line);
-	debugfs_remove(debugfs_lookup(name, NULL));
+	debugfs_lookup_and_remove(name, NULL);
 	uart_remove_one_port(&pch_uart_driver, &priv->port);
 	free_page((unsigned long)priv->rxbuf.buf);
 }
-- 
2.39.2