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 205ECC433EF for ; Mon, 24 Jan 2022 19:22:42 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1347646AbiAXTWh (ORCPT ); Mon, 24 Jan 2022 14:22:37 -0500 Received: from dfw.source.kernel.org ([139.178.84.217]:44216 "EHLO dfw.source.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1347648AbiAXTRB (ORCPT ); Mon, 24 Jan 2022 14:17:01 -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 dfw.source.kernel.org (Postfix) with ESMTPS id E920260917; Mon, 24 Jan 2022 19:17:00 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id B7865C340E5; Mon, 24 Jan 2022 19:16:59 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1643051820; bh=gUBygmoEBQDPFQekCp2li5xY7NKosJ7ZgGesRhBIraQ=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=SPRna9w79WLkd2jSwZBHZ5yA5EdfPbtr1bM3jd3rrE9iO7R8V0FhG/yf7y+GA0mHf iUGT/4uP6lj+yFSNQsybHiAWzK2TZ8HRcOjpc9X//DZdJghZUmXcndmouiiTXHpHfc ygLCwgvUVASEmje6E1NEmFAUylAAanIC7CNu18Hs= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Pavel Skripkin , Arnd Bergmann , Jakub Kicinski , Sasha Levin , syzbot+003c0a286b9af5412510@syzkaller.appspotmail.com Subject: [PATCH 4.19 097/239] net: mcs7830: handle usb read errors properly Date: Mon, 24 Jan 2022 19:42:15 +0100 Message-Id: <20220124183946.190555778@linuxfoundation.org> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20220124183943.102762895@linuxfoundation.org> References: <20220124183943.102762895@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: stable@vger.kernel.org From: Pavel Skripkin [ Upstream commit d668769eb9c52b150753f1653f7f5a0aeb8239d2 ] Syzbot reported uninit value in mcs7830_bind(). The problem was in missing validation check for bytes read via usbnet_read_cmd(). usbnet_read_cmd() internally calls usb_control_msg(), that returns number of bytes read. Code should validate that requested number of bytes was actually read. So, this patch adds missing size validation check inside mcs7830_get_reg() to prevent uninit value bugs Reported-and-tested-by: syzbot+003c0a286b9af5412510@syzkaller.appspotmail.com Fixes: 2a36d7083438 ("USB: driver for mcs7830 (aka DeLOCK) USB ethernet adapter") Signed-off-by: Pavel Skripkin Reviewed-by: Arnd Bergmann Link: https://lore.kernel.org/r/20220106225716.7425-1-paskripkin@gmail.com Signed-off-by: Jakub Kicinski Signed-off-by: Sasha Levin --- drivers/net/usb/mcs7830.c | 12 ++++++++++-- 1 file changed, 10 insertions(+), 2 deletions(-) diff --git a/drivers/net/usb/mcs7830.c b/drivers/net/usb/mcs7830.c index 5a47e5510ca82..c0f52a622964f 100644 --- a/drivers/net/usb/mcs7830.c +++ b/drivers/net/usb/mcs7830.c @@ -121,8 +121,16 @@ static const char driver_name[] = "MOSCHIP usb-ethernet driver"; static int mcs7830_get_reg(struct usbnet *dev, u16 index, u16 size, void *data) { - return usbnet_read_cmd(dev, MCS7830_RD_BREQ, MCS7830_RD_BMREQ, - 0x0000, index, data, size); + int ret; + + ret = usbnet_read_cmd(dev, MCS7830_RD_BREQ, MCS7830_RD_BMREQ, + 0x0000, index, data, size); + if (ret < 0) + return ret; + else if (ret < size) + return -ENODATA; + + return ret; } static int mcs7830_set_reg(struct usbnet *dev, u16 index, u16 size, const void *data) -- 2.34.1