From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id F11ACC433EF for ; Mon, 20 Dec 2021 14:59:26 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S238980AbhLTO7Y (ORCPT ); Mon, 20 Dec 2021 09:59:24 -0500 Received: from ams.source.kernel.org ([145.40.68.75]:35682 "EHLO ams.source.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S238434AbhLTO5Q (ORCPT ); Mon, 20 Dec 2021 09:57:16 -0500 Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ams.source.kernel.org (Postfix) with ESMTPS id 983DEB80EE8; Mon, 20 Dec 2021 14:57:15 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id D0E78C36AE9; Mon, 20 Dec 2021 14:57:13 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1640012234; bh=OGlqTETs1vYezaM2/ni4+RhFN5/5/Ss3x4WiekJMUKU=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=kXw/gEnYDFUQ4OpHmEFdmeMazlX6gAcXmWxZvMKmynPq+T0Of6LbUqFnwVUodHJFQ ieI+1GeaucnBzefKqZngLL2PXFjkQAy1SBlmtEahXd3jthRmGWNAqCK2/AwF4idEhG TEGQk71iDaXFiTFCyR3indbbMIAXOgK34yqS033Y= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Marian Postevca Subject: [PATCH 5.15 128/177] usb: gadget: u_ether: fix race in setting MAC address in setup phase Date: Mon, 20 Dec 2021 15:34:38 +0100 Message-Id: <20211220143044.382652365@linuxfoundation.org> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20211220143040.058287525@linuxfoundation.org> References: <20211220143040.058287525@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Marian Postevca commit 890d5b40908bfd1a79be018d2d297cf9df60f4ee upstream. When listening for notifications through netlink of a new interface being registered, sporadically, it is possible for the MAC to be read as zero. The zero MAC address lasts a short period of time and then switches to a valid random MAC address. This causes problems for netd in Android, which assumes that the interface is malfunctioning and will not use it. In the good case we get this log: InterfaceController::getCfg() ifName usb0 hwAddr 92:a8:f0:73:79:5b ipv4Addr 0.0.0.0 flags 0x1002 In the error case we get these logs: InterfaceController::getCfg() ifName usb0 hwAddr 00:00:00:00:00:00 ipv4Addr 0.0.0.0 flags 0x1002 netd : interfaceGetCfg("usb0") netd : interfaceSetCfg() -> ServiceSpecificException (99, "[Cannot assign requested address] : ioctl() failed") The reason for the issue is the order in which the interface is setup, it is first registered through register_netdev() and after the MAC address is set. Fixed by first setting the MAC address of the net_device and after that calling register_netdev(). Fixes: bcd4a1c40bee885e ("usb: gadget: u_ether: construct with default values and add setters/getters") Cc: stable@vger.kernel.org Signed-off-by: Marian Postevca Link: https://lore.kernel.org/r/20211204214912.17627-1-posteuca@mutex.one Signed-off-by: Greg Kroah-Hartman --- drivers/usb/gadget/function/u_ether.c | 16 ++++++---------- 1 file changed, 6 insertions(+), 10 deletions(-) --- a/drivers/usb/gadget/function/u_ether.c +++ b/drivers/usb/gadget/function/u_ether.c @@ -17,6 +17,7 @@ #include #include #include +#include #include "u_ether.h" @@ -861,19 +862,23 @@ int gether_register_netdev(struct net_de { struct eth_dev *dev; struct usb_gadget *g; - struct sockaddr sa; int status; if (!net->dev.parent) return -EINVAL; dev = netdev_priv(net); g = dev->gadget; + + net->addr_assign_type = NET_ADDR_RANDOM; + eth_hw_addr_set(net, dev->dev_mac); + status = register_netdev(net); if (status < 0) { dev_dbg(&g->dev, "register_netdev failed, %d\n", status); return status; } else { INFO(dev, "HOST MAC %pM\n", dev->host_mac); + INFO(dev, "MAC %pM\n", dev->dev_mac); /* two kinds of host-initiated state changes: * - iff DATA transfer is active, carrier is "on" @@ -881,15 +886,6 @@ int gether_register_netdev(struct net_de */ netif_carrier_off(net); } - sa.sa_family = net->type; - memcpy(sa.sa_data, dev->dev_mac, ETH_ALEN); - rtnl_lock(); - status = dev_set_mac_address(net, &sa, NULL); - rtnl_unlock(); - if (status) - pr_warn("cannot set self ethernet address: %d\n", status); - else - INFO(dev, "MAC %pM\n", dev->dev_mac); return status; }