From 517a281338322ff8293f988771c98aaa7205e457 Mon Sep 17 00:00:00 2001
From: Hyunwoo Kim <imv4bel@gmail.com>
Date: Thu, 17 Nov 2022 04:59:25 +0000
Subject: [PATCH] media: ttusb-dec: fix memory leak in ttusb_dec_exit_dvb()
Git-commit: 517a281338322ff8293f988771c98aaa7205e457
Patch-mainline: v6.4-rc3
References: CVE-2022-45887 bsc#1205762

Since dvb_frontend_detach() is not called in ttusb_dec_exit_dvb(),
which is called when the device is disconnected, dvb_frontend_free()
is not finally called.

This causes a memory leak just by repeatedly plugging and
unplugging the device.

Fix this issue by adding dvb_frontend_detach() to ttusb_dec_exit_dvb().

Link: https://lore.kernel.org/linux-media/20221117045925.14297-5-imv4bel@gmail.com
Signed-off-by: Hyunwoo Kim <imv4bel@gmail.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@kernel.org>
Acked-by: Takashi Iwai <tiwai@suse.de>

---
 drivers/media/usb/ttusb-dec/ttusb_dec.c | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/drivers/media/usb/ttusb-dec/ttusb_dec.c b/drivers/media/usb/ttusb-dec/ttusb_dec.c
index 38822cedd93a..c4474d4c44e2 100644
--- a/drivers/media/usb/ttusb-dec/ttusb_dec.c
+++ b/drivers/media/usb/ttusb-dec/ttusb_dec.c
@@ -1544,8 +1544,7 @@ static void ttusb_dec_exit_dvb(struct ttusb_dec *dec)
 	dvb_dmx_release(&dec->demux);
 	if (dec->fe) {
 		dvb_unregister_frontend(dec->fe);
-		if (dec->fe->ops.release)
-			dec->fe->ops.release(dec->fe);
+		dvb_frontend_detach(dec->fe);
 	}
 	dvb_unregister_adapter(&dec->adapter);
 }
-- 
2.35.3