KMSAN reported an uninitialized value use in rtl8150_open(). Initialize rx_skb->data and intr_buff before submitting URBs to ensure memory is in a defined state. Reported-by: syzbot+b4d5d8faea6996fd@syzkaller.appspotmail.com Signed-off-by: Dharanitharan R --- drivers/net/usb/rtl8150.c | 21 ++++++++++++++------- 1 file changed, 14 insertions(+), 7 deletions(-) diff --git a/drivers/net/usb/rtl8150.c b/drivers/net/usb/rtl8150.c index 278e6cb6f4d9..f1a868f0032e 100644 --- a/drivers/net/usb/rtl8150.c +++ b/drivers/net/usb/rtl8150.c @@ -719,14 +719,15 @@ static netdev_tx_t rtl8150_start_xmit(struct sk_buff *skb, static void set_carrier(struct net_device *netdev) { - rtl8150_t *dev = netdev_priv(netdev); - short tmp; + rtl8150_t *dev = netdev_priv(netdev); + short tmp; - get_registers(dev, CSCR, 2, &tmp); - if (tmp & CSCR_LINK_STATUS) - netif_carrier_on(netdev); - else - netif_carrier_off(netdev); + /* Only use tmp if get_registers() succeeds */ + if (!get_registers(dev, CSCR, 2, &tmp) && + (tmp & CSCR_LINK_STATUS)) + netif_carrier_on(netdev); + else + netif_carrier_off(netdev); } static int rtl8150_open(struct net_device *netdev) @@ -741,6 +742,10 @@ static int rtl8150_open(struct net_device *netdev) set_registers(dev, IDR, 6, netdev->dev_addr); + /* Fix: initialize memory before using it (KMSAN uninit-value) */ + memset(dev->rx_skb->data, 0, RTL8150_MTU); + memset(dev->intr_buff, 0, INTBUFSIZE); + usb_fill_bulk_urb(dev->rx_urb, dev->udev, usb_rcvbulkpipe(dev->udev, 1), dev->rx_skb->data, RTL8150_MTU, read_bulk_callback, dev); if ((res = usb_submit_urb(dev->rx_urb, GFP_KERNEL))) { @@ -749,6 +754,7 @@ static int rtl8150_open(struct net_device *netdev) dev_warn(&netdev->dev, "rx_urb submit failed: %d\n", res); return res; } + usb_fill_int_urb(dev->intr_urb, dev->udev, usb_rcvintpipe(dev->udev, 3), dev->intr_buff, INTBUFSIZE, intr_callback, dev, dev->intr_interval); @@ -759,6 +765,7 @@ static int rtl8150_open(struct net_device *netdev) usb_kill_urb(dev->rx_urb); return res; } + enable_net_traffic(dev); set_carrier(netdev); netif_start_queue(netdev); -- 2.43.0