[PATCH 5.14 265/849] media: usb: dvd-usb: fix uninit-value bug in dibusb_read_eeprom_byte()

Greg Kroah-Hartman
2021-11-16T01:33:58Z

From: Anant Thazhemadam <anant.thazhemadam@gmail.com>

[ Upstream commit 899a61a3305d49e8a712e9ab20d0db94bde5929f ]

In dibusb_read_eeprom_byte(), if dibusb_i2c_msg() fails, val gets
assigned an value that's not properly initialized.
Using kzalloc() in place of kmalloc() for the buffer fixes this issue,
as the val can now be set to 0 in the event dibusb_i2c_msg() fails.

Reported-by: syzbot+e27b4fd589762b0b9329@syzkaller.appspotmail.com
Tested-by: syzbot+e27b4fd589762b0b9329@syzkaller.appspotmail.com
Signed-off-by: Anant Thazhemadam <anant.thazhemadam@gmail.com>
Signed-off-by: Sean Young <sean@mess.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/media/usb/dvb-usb/dibusb-common.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/media/usb/dvb-usb/dibusb-common.c b/drivers/media/usb/dvb-usb/dibusb-common.c
index 02b51d1a1b67c..aff60c10cb0b2 100644
--- a/drivers/media/usb/dvb-usb/dibusb-common.c
+++ b/drivers/media/usb/dvb-usb/dibusb-common.c
@@ -223,7 +223,7 @@ int dibusb_read_eeprom_byte(struct dvb_usb_device *d, u8 offs, u8 *val)
u8 *buf;
int rc;

- buf = kmalloc(2, GFP_KERNEL);
+ buf = kzalloc(2, GFP_KERNEL);
if (!buf)
return -ENOMEM;

--
2.33.0