diff --git a/target/linux/generic/pending-6.6/155-usbnet-restore-usb%d-name-exception-for-local-mac-addresses.patch b/target/linux/generic/pending-6.6/155-usbnet-restore-usb%d-name-exception-for-local-mac-addresses.patch new file mode 100644 index 00000000000..0d32800cbc9 --- /dev/null +++ b/target/linux/generic/pending-6.6/155-usbnet-restore-usb%d-name-exception-for-local-mac-addresses.patch @@ -0,0 +1,63 @@ +From linux-netdev Tue Dec 03 13:04:55 2024 +From: Dominique Martinet +Date: Tue, 03 Dec 2024 13:04:55 +0000 +To: linux-netdev +Subject: [PATCH] net: usb: usbnet: restore usb%d name exception for local mac addresses +Message-Id: <20241203130457.904325-1-asmadeus () codewreck ! org> +X-MARC-Message: https://marc.info/?l=linux-netdev&m=173323431631309 + +From: Dominique Martinet + +The previous commit assumed that local addresses always came from the +kernel, but some devices hand out local mac addresses so we ended up +with point-to-point devices with a mac set by the driver, renaming to +eth%d when they used to be named usb%d. + +Userspace should not rely on device name, but for the sake of stability +restore the local mac address check portion of the naming exception: +point to point devices which either have no mac set by the driver or +have a local mac handed out by the driver will keep the usb%d name. + +Fixes: 8a7d12d674ac ("net: usb: usbnet: fix name regression") +Signed-off-by: Dominique Martinet +--- + drivers/net/usb/usbnet.c | 20 ++++++++++++++------ + 1 file changed, 14 insertions(+), 6 deletions(-) + +--- a/drivers/net/usb/usbnet.c ++++ b/drivers/net/usb/usbnet.c +@@ -178,6 +178,17 @@ int usbnet_get_ethernet_addr(struct usbn + } + EXPORT_SYMBOL_GPL(usbnet_get_ethernet_addr); + ++static bool usbnet_needs_usb_name_format(struct usbnet *dev, struct net_device *net) ++{ ++ /* Point to point devices which don't have a real MAC address ++ * (or report a fake local one) have historically used the usb%d ++ * naming. Preserve this.. ++ */ ++ return (dev->driver_info->flags & FLAG_POINTTOPOINT) != 0 && ++ (is_zero_ether_addr(net->dev_addr) || ++ is_local_ether_addr(net->dev_addr)); ++} ++ + static void intr_complete (struct urb *urb) + { + struct usbnet *dev = urb->context; +@@ -1766,13 +1777,10 @@ usbnet_probe (struct usb_interface *udev + if (status < 0) + goto out1; + +- // heuristic: "usb%d" for links we know are two-host, +- // else "eth%d" when there's reasonable doubt. userspace +- // can rename the link if it knows better. ++ /* heuristic: rename to "eth%d" if we are not sure this link ++ * is two-host (these links keep "usb%d") */ + if ((dev->driver_info->flags & FLAG_ETHER) != 0 && +- ((dev->driver_info->flags & FLAG_POINTTOPOINT) == 0 || +- /* somebody touched it*/ +- !is_zero_ether_addr(net->dev_addr))) ++ !usbnet_needs_usb_name_format(dev, net)) + strscpy(net->name, "eth%d", sizeof(net->name)); + /* WLAN devices should always be named "wlan%d" */ + if ((dev->driver_info->flags & FLAG_WLAN) != 0)