From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id C3AA4267B89; Tue, 8 Apr 2025 12:07:29 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1744114049; cv=none; b=C0eFIbmVNECah+Li6Uh0g0QCVcUPOpbfJOeWyDCSsPV72scAH4M5hklLft4XpzWKdblH8wDKy7C5fsgkUqdFUAXLQ8LH1tp79wILivxudqVu+PkFfDh7NESW4dFMUuyodEHRIzek+YWIG0Tk05ri5mHNUe5uh5kDnPwTjk+peBU= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1744114049; c=relaxed/simple; bh=n83DTev8TuKt8atIN7FBVUFAgLo4ACIevw1ZyvUyv0Q=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=rfCCkPUK5+Ael0thW7MJPVbYT4p/fEbGB2LzmAOqCiLVqRfh6gEyhUSDPda8VOeY/LinfJbTUfmmqVUC4jgNTm0r+K5/LOnF8x/8o1uhfY0MPKGZdy0pYVbuYbmn6tqca0g20DFGhWMreCKLA6tLjtSAYD6tgsuDmSFq5d9MLCc= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=y3X+/ev2; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="y3X+/ev2" Received: by smtp.kernel.org (Postfix) with ESMTPSA id E151AC4CEE5; Tue, 8 Apr 2025 12:07:28 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1744114049; bh=n83DTev8TuKt8atIN7FBVUFAgLo4ACIevw1ZyvUyv0Q=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=y3X+/ev2eqAAVyq1UI7mhU3FN/iAmYptU2ICA1SBU17jEPkF+qNaXxxDE42ld2Oce Ahvr1M2o8cOvbEpuMksSEItWIs0owvAlLO/2JTc11vB0tv6NSJpJyD6YAXBlESx+ZA 1mUMN7/pA2o4dRzFCwoZypCXgCKxFv5rN6Xvxcoo= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Ahmed Naseef , Dominique Martinet , Oliver Neukum , Jakub Kicinski Subject: [PATCH 5.4 077/154] net: usb: usbnet: restore usb%d name exception for local mac addresses Date: Tue, 8 Apr 2025 12:50:18 +0200 Message-ID: <20250408104817.778850790@linuxfoundation.org> X-Mailer: git-send-email 2.49.0 In-Reply-To: <20250408104815.295196624@linuxfoundation.org> References: <20250408104815.295196624@linuxfoundation.org> User-Agent: quilt/0.68 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 5.4-stable review patch. If anyone has any objections, please let me know. ------------------ From: Dominique Martinet commit 2ea396448f26d0d7d66224cb56500a6789c7ed07 upstream. commit 8a7d12d674ac ("net: usb: usbnet: fix name regression") 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. (some USB LTE modems are known to hand out a stable mac from the locally administered range; that mac appears to be random (different for mulitple devices) and can be reset with device-specific commands, so while such devices would benefit from getting a OUI reserved, we have to deal with these and might as well preserve the existing behavior to avoid breaking fragile openwrt configurations and such on upgrade.) Link: https://lkml.kernel.org/r/20241203130457.904325-1-asmadeus@codewreck.org Fixes: 8a7d12d674ac ("net: usb: usbnet: fix name regression") Cc: stable@vger.kernel.org Tested-by: Ahmed Naseef Signed-off-by: Dominique Martinet Acked-by: Oliver Neukum Link: https://patch.msgid.link/20250326-usbnet_rename-v2-1-57eb21fcff26@atmark-techno.com Signed-off-by: Jakub Kicinski Signed-off-by: Greg Kroah-Hartman --- drivers/net/usb/usbnet.c | 21 +++++++++++++++------ 1 file changed, 15 insertions(+), 6 deletions(-) --- a/drivers/net/usb/usbnet.c +++ b/drivers/net/usb/usbnet.c @@ -167,6 +167,17 @@ 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; @@ -1730,13 +1741,11 @@ 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)