From: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Date: Mon, 29 May 2023 05:58:36 +0000 (+0200)
Subject: media: dvb-usb: m920x: Fix a potential memory leak in m920x_i2c_xfer()
X-Git-Tag: v4.14.326~112
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=809623fedc31f4e74039d93bb75a8993635d7534;p=thirdparty%2Fkernel%2Fstable.git

media: dvb-usb: m920x: Fix a potential memory leak in m920x_i2c_xfer()

[ Upstream commit ea9ef6c2e001c5dc94bee35ebd1c8a98621cf7b8 ]

'read' is freed when it is known to be NULL, but not when a read error
occurs.

Revert the logic to avoid a small leak, should a m920x_read() call fail.

Fixes: a2ab06d7c4d6 ("media: m920x: don't use stack on USB reads")
Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---

diff --git a/drivers/media/usb/dvb-usb/m920x.c b/drivers/media/usb/dvb-usb/m920x.c
index 8a43e2415686a..2a421bd9912bc 100644
--- a/drivers/media/usb/dvb-usb/m920x.c
+++ b/drivers/media/usb/dvb-usb/m920x.c
@@ -283,7 +283,6 @@ static int m920x_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg msg[], int nu
 			char *read = kmalloc(1, GFP_KERNEL);
 			if (!read) {
 				ret = -ENOMEM;
-				kfree(read);
 				goto unlock;
 			}
 
@@ -294,8 +293,10 @@ static int m920x_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg msg[], int nu
 
 				if ((ret = m920x_read(d->udev, M9206_I2C, 0x0,
 						      0x20 | stop,
-						      read, 1)) != 0)
+						      read, 1)) != 0) {
+					kfree(read);
 					goto unlock;
+				}
 				msg[i].buf[j] = read[0];
 			}