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 38E9BC77B7C for ; Sun, 28 May 2023 19:20:14 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229895AbjE1TUN (ORCPT ); Sun, 28 May 2023 15:20:13 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:38664 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229893AbjE1TUM (ORCPT ); Sun, 28 May 2023 15:20:12 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 9AE1EA6 for ; Sun, 28 May 2023 12:20:11 -0700 (PDT) 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 dfw.source.kernel.org (Postfix) with ESMTPS id 2C1B261AA6 for ; Sun, 28 May 2023 19:20:11 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 48900C433D2; Sun, 28 May 2023 19:20:10 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1685301610; bh=+LCOnBj3keaLcR+E+3OYLG9rfTfm8+9kpyV63StUHrc=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=pxE21etgeFXl2sN6C9b/opDbFB2t06Mq0O1cl+0btHBv7AagG8+YxYnO3loyMADad ra+71WD096gxqhr7nLDiYEI1BvILsm/pxIHZbNUfkRwYx10y8L8J6qM4cii4iAG9sE I3MCUlBeDD1R5sgchQHN33qw8atwzH8BAU3H/BHc= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, =?UTF-8?q?Konrad=20Gr=C3=A4fe?= , Sasha Levin Subject: [PATCH 4.19 098/132] usb: gadget: u_ether: Fix host MAC address case Date: Sun, 28 May 2023 20:10:37 +0100 Message-Id: <20230528190836.651384328@linuxfoundation.org> X-Mailer: git-send-email 2.40.1 In-Reply-To: <20230528190833.565872088@linuxfoundation.org> References: <20230528190833.565872088@linuxfoundation.org> User-Agent: quilt/0.67 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Konrad Gräfe [ Upstream commit 3c0f4f09c063e143822393d99cb2b19a85451c07 ] The CDC-ECM specification [1] requires to send the host MAC address as an uppercase hexadecimal string in chapter "5.4 Ethernet Networking Functional Descriptor": The Unicode character is chosen from the set of values 30h through 39h and 41h through 46h (0-9 and A-F). However, snprintf(.., "%pm", ..) generates a lowercase MAC address string. While most host drivers are tolerant to this, UsbNcm.sys on Windows 10 is not. Instead it uses a different MAC address with all bytes set to zero including and after the first byte containing a lowercase letter. On Windows 11 Microsoft fixed it, but apparently they did not backport the fix. This change fixes the issue by upper-casing the MAC to comply with the specification. [1]: https://www.usb.org/document-library/class-definitions-communication-devices-12, file ECM120.pdf Fixes: bcd4a1c40bee ("usb: gadget: u_ether: construct with default values and add setters/getters") Cc: stable@vger.kernel.org Signed-off-by: Konrad Gräfe Link: https://lore.kernel.org/r/20230505143640.443014-1-k.graefe@gateware.de Signed-off-by: Greg Kroah-Hartman Signed-off-by: Sasha Levin --- drivers/usb/gadget/function/u_ether.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/drivers/usb/gadget/function/u_ether.c b/drivers/usb/gadget/function/u_ether.c index 561a090ced6de..7d9a551c47f98 100644 --- 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 #include "u_ether.h" @@ -940,6 +941,8 @@ int gether_get_host_addr_cdc(struct net_device *net, char *host_addr, int len) dev = netdev_priv(net); snprintf(host_addr, len, "%pm", dev->host_mac); + string_upper(host_addr, host_addr); + return strlen(host_addr); } EXPORT_SYMBOL_GPL(gether_get_host_addr_cdc); -- 2.39.2