From 22be5a10d0b24eec9e45decd15d7e6112b25f080 Mon Sep 17 00:00:00 2001
From: Dongliang Mu <mudongliangabcd@gmail.com>
Date: Mon, 1 Nov 2021 09:55:39 +0000
Subject: [PATCH] media: em28xx: fix memory leak in em28xx_init_dev
Git-commit: 22be5a10d0b24eec9e45decd15d7e6112b25f080
References: git-fixes
Patch-mainline: v5.17-rc1

In the em28xx_init_rev, if em28xx_audio_setup fails, this function fails
to deallocate the media_dev allocated in the em28xx_media_device_init.

Fix this by adding em28xx_unregister_media_device to free media_dev.

BTW, this patch is tested in my local syzkaller instance, and it can
prevent the memory leak from occurring again.

CC: Pavel Skripkin <paskripkin@gmail.com>
Fixes: 37ecc7b1278f ("[media] em28xx: add media controller support")
Signed-off-by: Dongliang Mu <mudongliangabcd@gmail.com>
Reported-by: syzkaller <syzkaller@googlegroups.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Signed-off-by: Oliver Neukum <oneukum@suse.com>
---
 drivers/media/usb/em28xx/em28xx-cards.c |   18 ++++++++++++------
 1 file changed, 12 insertions(+), 6 deletions(-)

--- a/drivers/media/usb/em28xx/em28xx-cards.c
+++ b/drivers/media/usb/em28xx/em28xx-cards.c
@@ -3399,8 +3399,10 @@ static int em28xx_init_dev(struct em28xx
 
 	if (dev->is_audio_only) {
 		retval = em28xx_audio_setup(dev);
-		if (retval)
-			return -ENODEV;
+		if (retval) {
+			retval = -ENODEV;
+			goto err_deinit_media;
+		}
 		em28xx_init_extension(dev);
 
 		return 0;
@@ -3430,7 +3432,7 @@ static int em28xx_init_dev(struct em28xx
 		dev_err(&dev->intf->dev,
 			"%s: em28xx_i2c_register bus 0 - error [%d]!\n",
 		       __func__, retval);
-		return retval;
+		goto err_deinit_media;
 	}
 
 	/* register i2c bus 1 */
@@ -3446,9 +3448,7 @@ static int em28xx_init_dev(struct em28xx
 			       "%s: em28xx_i2c_register bus 1 - error [%d]!\n",
 			       __func__, retval);
 
-			em28xx_i2c_unregister(dev, 0);
-
-			return retval;
+			goto err_unreg_i2c;
 		}
 	}
 
@@ -3456,6 +3456,12 @@ static int em28xx_init_dev(struct em28xx
 	em28xx_card_setup(dev);
 
 	return 0;
+
+err_unreg_i2c:
+	em28xx_i2c_unregister(dev, 0);
+err_deinit_media:
+	em28xx_unregister_media_device(dev);
+	return retval;
 }
 
 /* high bandwidth multiplier, as encoded in highspeed endpoint descriptors */