[PATCH 5.12 018/700] media: dvb-usb: fix wrong definition

From: Greg Kroah-Hartman
Date: Mon Jul 12 2021 - 03:19:15 EST


From: Pavel Skripkin <paskripkin@xxxxxxxxx>

commit c680ed46e418e9c785d76cf44eb33bfd1e8cf3f6 upstream.

syzbot reported WARNING in vmalloc. The problem
was in zero size passed to vmalloc.

The root case was in wrong cxusb_bluebird_lgz201_properties
definition. adapter array has only 1 entry, but num_adapters was
2.

Call Trace:
__vmalloc_node mm/vmalloc.c:2963 [inline]
vmalloc+0x67/0x80 mm/vmalloc.c:2996
dvb_dmx_init+0xe4/0xb90 drivers/media/dvb-core/dvb_demux.c:1251
dvb_usb_adapter_dvb_init+0x564/0x860 drivers/media/usb/dvb-usb/dvb-usb-dvb.c:184
dvb_usb_adapter_init drivers/media/usb/dvb-usb/dvb-usb-init.c:86 [inline]
dvb_usb_init drivers/media/usb/dvb-usb/dvb-usb-init.c:184 [inline]
dvb_usb_device_init.cold+0xc94/0x146e drivers/media/usb/dvb-usb/dvb-usb-init.c:308
cxusb_probe+0x159/0x5e0 drivers/media/usb/dvb-usb/cxusb.c:1634

Fixes: 4d43e13f723e ("V4L/DVB (4643): Multi-input patch for DVB-USB device")
Cc: stable@xxxxxxxxxxxxxxx
Reported-by: syzbot+7336195c02c1bd2f64e1@xxxxxxxxxxxxxxxxxxxxxxxxx
Signed-off-by: Pavel Skripkin <paskripkin@xxxxxxxxx>
Signed-off-by: Sean Young <sean@xxxxxxxx>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
drivers/media/usb/dvb-usb/cxusb.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

--- a/drivers/media/usb/dvb-usb/cxusb.c
+++ b/drivers/media/usb/dvb-usb/cxusb.c
@@ -1947,7 +1947,7 @@ static struct dvb_usb_device_properties

.size_of_priv = sizeof(struct cxusb_state),

- .num_adapters = 2,
+ .num_adapters = 1,
.adapter = {
{
.num_frontends = 1,