From: Anant Thazhemadam anant.thazhemadam@gmail.com
commit f45a4248ea4cc13ed50618ff066849f9587226b2 upstream.
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 Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- drivers/net/usb/rtl8150.c | 16 ++++++++++++---- 1 file changed, 12 insertions(+), 4 deletions(-)
--- a/drivers/net/usb/rtl8150.c +++ b/drivers/net/usb/rtl8150.c @@ -274,12 +274,20 @@ static int write_mii_word(rtl8150_t * de 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)