On 20-10-12 12:11:18, Joe Perches wrote:
> On Mon, 2020-10-12 at 15:02 -0400, Sasha Levin wrote:
> > From: Anant Thazhemadam <anant.thazhema...@gmail.com>
> >
> > [ Upstream commit f45a4248ea4cc13ed50618ff066849f9587226b2 ]
> >
> > When get_registers() fails in set_ethernet_addr(),the uninitialized
> > value of node_id gets copied over as the address.
> > So, check the return value of get_registers().
> >
> > If get_registers() executed successfully (i.e., it returns
> > sizeof(node_id)), copy over the MAC address using ether_addr_copy()
> > (instead of using memcpy()).
> >
> > Else, if get_registers() failed instead, a randomly generated MAC
> > address is set as the MAC address instead.
>
> This autosel is premature.
>
> This patch always sets a random MAC.
> See the follow on patch: https://lkml.org/lkml/2020/10/11/131
> To my knowledge, this follow-ob has yet to be applied:
ACK, the follow-on patch has got the correct semantics.
Petko
> > diff --git a/drivers/net/usb/rtl8150.c b/drivers/net/usb/rtl8150.c
> []
> > @@ -274,12 +274,20 @@ static int write_mii_word(rtl8150_t * dev, u8 phy,
> > __u8 indx, u16 reg)
> > return 1;
> > }
> >
> > -static inline void set_ethernet_addr(rtl8150_t * dev)
> > +static void set_ethernet_addr(rtl8150_t *dev)
> > {
> > - u8 node_id[6];
> > + u8 node_id[ETH_ALEN];
> > + int ret;
> > +
> > + ret = get_registers(dev, IDR, sizeof(node_id), node_id);
> >
> > - get_registers(dev, IDR, sizeof(node_id), node_id);
> > - memcpy(dev->netdev->dev_addr, node_id, sizeof(node_id));
> > + if (ret == sizeof(node_id)) {
>
> So this needs to use
> if (!ret) {
>
> or
> if (ret < 0)
>
> and reversed code blocks
>
> > + ether_addr_copy(dev->netdev->dev_addr, node_id);
> > + } else {
> > + eth_hw_addr_random(dev->netdev);
> > + netdev_notice(dev->netdev, "Assigned a random MAC address:
> > %pM\n",
> > + dev->netdev->dev_addr);
> > + }
> > }
> >
> > static int rtl8150_set_mac_address(struct net_device *netdev, void *p)
>
>
