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 X-Spam-Level: X-Spam-Status: No, score=-12.7 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 10C5DC433FE for ; Wed, 9 Dec 2020 00:37:22 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id DB32323AA8 for ; Wed, 9 Dec 2020 00:37:21 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730940AbgLIAg7 (ORCPT ); Tue, 8 Dec 2020 19:36:59 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:49620 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725906AbgLIAg7 (ORCPT ); Tue, 8 Dec 2020 19:36:59 -0500 Received: from mail-ej1-x641.google.com (mail-ej1-x641.google.com [IPv6:2a00:1450:4864:20::641]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id E40B0C0613CF; Tue, 8 Dec 2020 16:36:18 -0800 (PST) Received: by mail-ej1-x641.google.com with SMTP id x16so483609ejj.7; Tue, 08 Dec 2020 16:36:18 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=mkMFIqftA6fOka00URf8NhOMR4eJXlK1B5kNwAoNQh4=; b=EuOPJQJeFYNRtbLszFRpPb7sdtooqzYIpAVUXtaqw+jHTS2+NHM8R84f6d1gEB3y2e 7/OVlPqVbbJnifASDQ6N/cfq5IGHfkK6PeZ3nGQ9/h+MC3w0P7sX3PsqywykDVk80bP0 PA+JzIElgGXUpjAYvE5wA2rZoHTRwyZnABXL0WjcN+3N8paLtbE0bhubpLYriWwThMxg T4z6BziUr3UByTbWtFm7uiMqUFRfG+1iWNZcRlFs2z7Wtc+TSbohgSEKfPHCyKlIpAFs fWfwKMf0bFFkk4P++vhkwgnB0gR9IBFr0VAIJkmjL4lEJqYF+AxnBfrhC3BuA4eK5HrQ Wbig== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=mkMFIqftA6fOka00URf8NhOMR4eJXlK1B5kNwAoNQh4=; b=fG7fqTzXypiLCzKQlvJLvldLbGU0iXACuPpZX5mk2TO1qWGhRgGdykzSMKlqSLIqlA 75tV1BQ8gkqVAjHXG37cSuObWOPh32ztQUaJISwFzSR3E4fp1QRQZRP1NbKRXUYv3dae UP73LKhM3UZ0OPRUZS4youKC9qJ8gP2EcUmAx1BjA60TkaP8l+pGgZnDX/MR8gfsTHj9 K/e9ENulNGx6nCMPHvtZyPb/UMBfIIc2ch4OJNC72wHABMkDOkvXwPtGr2cbcXG1Nk+z YjH/bCp/2d9FAd5okjJCGVXxq0OwHs+nZPzMsFhhwgPkn6BzQ1Ah2yRLDdUfE7u3axku bZYg== X-Gm-Message-State: AOAM530T5OXRUUerMubKOs7rc+qxNCljHCBtlJkLrNVvSpGYV+hJWA9B G9kq3gj3aePPby/manJG2k/GStdLvU1e7TAJTI0= X-Google-Smtp-Source: ABdhPJxf5Ixnqs9paYGQBJNuLiyZHP+oImATrwLI0x1RD6F7YlOikrK9B5P/b4ND1Mim0+OfALId61aQlJ3k7JosiNo= X-Received: by 2002:a17:906:298c:: with SMTP id x12mr268679eje.244.1607474177673; Tue, 08 Dec 2020 16:36:17 -0800 (PST) MIME-Version: 1.0 References: <20201208124523.8169-1-ruc_zhangxiaohui@163.com> In-Reply-To: <20201208124523.8169-1-ruc_zhangxiaohui@163.com> From: Julian Calaby Date: Wed, 9 Dec 2020 11:36:05 +1100 Message-ID: Subject: Re: [PATCH 1/1] mwifiex: Fix possible buffer overflows in mwifiex_config_scan To: Xiaohui Zhang Cc: Amitkumar Karwar , Ganapathi Bhat , Xinming Hu , Kalle Valo , "David S. Miller" , Jakub Kicinski , linux-wireless@vger.kernel.org, netdev@vger.kernel.org, LKML Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: linux-wireless@vger.kernel.org Hi Xiaohui, On Wed, Dec 9, 2020 at 12:07 AM Xiaohui Zhang wrote: > > From: Zhang Xiaohui > > mwifiex_config_scan() calls memcpy() without checking > the destination size may trigger a buffer overflower, > which a local user could use to cause denial of service > or the execution of arbitrary code. > Fix it by putting the length check before calling memcpy(). > > Signed-off-by: Zhang Xiaohui > --- > drivers/net/wireless/marvell/mwifiex/scan.c | 2 ++ > 1 file changed, 2 insertions(+) > > diff --git a/drivers/net/wireless/marvell/mwifiex/scan.c b/drivers/net/wireless/marvell/mwifiex/scan.c > index c2a685f63..b1d90678f 100644 > --- a/drivers/net/wireless/marvell/mwifiex/scan.c > +++ b/drivers/net/wireless/marvell/mwifiex/scan.c > @@ -930,6 +930,8 @@ mwifiex_config_scan(struct mwifiex_private *priv, > "DIRECT-", 7)) > wildcard_ssid_tlv->max_ssid_length = 0xfe; > > + if (ssid_len > 1) > + ssid_len = 1; > memcpy(wildcard_ssid_tlv->ssid, > user_scan_in->ssid_list[i].ssid, ssid_len); Can ssid_len ever be 0 here? If it can't, should we just set ssid_len to 1 unconditionally? If it can, should we just skip the memcpy as it won't do anything? Thanks, -- Julian Calaby Email: julian.calaby@gmail.com Profile: http://www.google.com/profiles/julian.calaby/