media: usb: dvd-usb: fix uninit-value bug in dibusb_read_eeprom_byte()

BugLink: https://bugs.launchpad.net/bugs/1951822
[ 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>
Signed-off-by: Paolo Pisati <paolo.pisati@canonical.com>

diff --git a/drivers/media/usb/dvb-usb/dibusb-common.c b/drivers/media/usb/dvb-usb/dibusb-common.c
index 02b51d1a1b67c9fb3eda5a9dd84faf5ecd6f08f0..aff60c10cb0b2c9e92c899c8504538a97012d615 100644 (file)
--- 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;