[PATCH 5.10 206/406] media: dvb-usb: m920x: Fix a potential memory leak in m920x_i2c_xfer()

Greg Kroah-Hartman
2023-09-17T19:32:10Z

From: Christophe JAILLET <christophe.jaillet@wanadoo.fr>

[ 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>
---
drivers/media/usb/dvb-usb/m920x.c | 5 +++--
1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/drivers/media/usb/dvb-usb/m920x.c b/drivers/media/usb/dvb-usb/m920x.c
index 691e05833db19..da81fa189b5d5 100644
--- a/drivers/media/usb/dvb-usb/m920x.c
+++ b/drivers/media/usb/dvb-usb/m920x.c
@@ -277,7 +277,6 @@ 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;
}

@@ -288,8 +287,10 @@ 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];
}

--
2.40.1