On 20-10-11 11:33:00, Joe Perches wrote: > On Sun, 2020-10-11 at 10:59 -0700, Jakub Kicinski wrote: > > On Sun, 11 Oct 2020 23:00:30 +0530 Anant Thazhemadam wrote: > > > In set_ethernet_addr(), if get_registers() succeeds, the ethernet address > > > that was read must be copied over. Otherwise, a random ethernet address > > > must be assigned. > > > > > > get_registers() returns 0 if successful, and negative error number > > > otherwise. However, in set_ethernet_addr(), this return value is > > > incorrectly checked. > > > > > > Since this return value will never be equal to sizeof(node_id), a > > > random MAC address will always be generated and assigned to the > > > device; even in cases when get_registers() is successful. > > > > > > Correctly modifying the condition that checks if get_registers() was > > > successful or not fixes this problem, and copies the ethernet address > > > appropriately. > > There are many unchecked uses of set_registers and get_registers > in this file. > > If failures are really expected, then it might be better to fix > them up too. Checking the return value of each get/set_registers() is going to be a PITA and not very helpful. Doing so when setting the MAC address _does_ make sense as in that case it is not a hard error. In almost all other occasions if usb_control_msg_send/recv() return an error i'd rather dump an error message (from within get/set_registers()) and let the user decide whether to get rid of this adapter or start debugging it. cheers, Petko > $ git grep -w '[gs]et_registers' drivers/net/usb/rtl8150.c > drivers/net/usb/rtl8150.c:static int get_registers(rtl8150_t * dev, u16 indx, u16 size, void *data) > drivers/net/usb/rtl8150.c:static int set_registers(rtl8150_t * dev, u16 indx, u16 size, const void *data) > drivers/net/usb/rtl8150.c: set_registers(dev, PHYADD, sizeof(data), data); > drivers/net/usb/rtl8150.c: set_registers(dev, PHYCNT, 1, &tmp); > drivers/net/usb/rtl8150.c: get_registers(dev, PHYCNT, 1, data); > drivers/net/usb/rtl8150.c: get_registers(dev, PHYDAT, 2, data); > drivers/net/usb/rtl8150.c: set_registers(dev, PHYADD, sizeof(data), data); > drivers/net/usb/rtl8150.c: set_registers(dev, PHYCNT, 1, &tmp); > drivers/net/usb/rtl8150.c: get_registers(dev, PHYCNT, 1, data); > drivers/net/usb/rtl8150.c: ret = get_registers(dev, IDR, sizeof(node_id), node_id); > drivers/net/usb/rtl8150.c: set_registers(dev, IDR, netdev->addr_len, netdev->dev_addr); > drivers/net/usb/rtl8150.c: get_registers(dev, CR, 1, &cr); > drivers/net/usb/rtl8150.c: set_registers(dev, CR, 1, &cr); > drivers/net/usb/rtl8150.c: set_registers(dev, IDR_EEPROM + (i * 2), 2, > drivers/net/usb/rtl8150.c: set_registers(dev, CR, 1, &cr); > drivers/net/usb/rtl8150.c: set_registers(dev, CR, 1, &data); > drivers/net/usb/rtl8150.c: get_registers(dev, CR, 1, &data); > drivers/net/usb/rtl8150.c: set_registers(dev, RCR, 1, &rcr); > drivers/net/usb/rtl8150.c: set_registers(dev, TCR, 1, &tcr); > drivers/net/usb/rtl8150.c: set_registers(dev, CR, 1, &cr); > drivers/net/usb/rtl8150.c: get_registers(dev, MSR, 1, &msr); > drivers/net/usb/rtl8150.c: get_registers(dev, CR, 1, &cr); > drivers/net/usb/rtl8150.c: set_registers(dev, CR, 1, &cr); > drivers/net/usb/rtl8150.c: get_registers(dev, CSCR, 2, &tmp); > drivers/net/usb/rtl8150.c: set_registers(dev, IDR, 6, netdev->dev_addr); > drivers/net/usb/rtl8150.c: get_registers(dev, BMCR, 2, &bmcr); > drivers/net/usb/rtl8150.c: get_registers(dev, ANLP, 2, &lpa); > > >
