net: usb: rtl8150: set random MAC address when set_ethernet_addr() fails

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.

Reported-by: syzbot+abbc768b560c84d92fd3@syzkaller.appspotmail.com
Tested-by: syzbot+abbc768b560c84d92fd3@syzkaller.appspotmail.com
Acked-by: Petko Manolov <petkan@nucleusys.com>
Signed-off-by: Anant Thazhemadam <anant.thazhemadam@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Anant Thazhemadam 2020-10-05 18:59:58 +05:30 committed by David S. Miller
parent 017512a07e
commit f45a4248ea

View File

@ -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;
get_registers(dev, IDR, sizeof(node_id), node_id);
memcpy(dev->netdev->dev_addr, node_id, sizeof(node_id));
ret = get_registers(dev, IDR, sizeof(node_id), node_id);
if (ret == sizeof(node_id)) {
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)