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 8B837C4332F for ; Thu, 20 Oct 2022 08:39:23 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230082AbiJTIjV (ORCPT ); Thu, 20 Oct 2022 04:39:21 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:55016 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229794AbiJTIjT (ORCPT ); Thu, 20 Oct 2022 04:39:19 -0400 Received: from mail-wr1-x42e.google.com (mail-wr1-x42e.google.com [IPv6:2a00:1450:4864:20::42e]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id A41E818C96B for ; Thu, 20 Oct 2022 01:39:17 -0700 (PDT) Received: by mail-wr1-x42e.google.com with SMTP id b4so33133227wrs.1 for ; Thu, 20 Oct 2022 01:39:17 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=content-transfer-encoding:in-reply-to:from:references:cc:to :content-language:subject:user-agent:mime-version:date:message-id :from:to:cc:subject:date:message-id:reply-to; bh=MYiaRsw3d498ajPipBA6kI+35MHXcbys3QG+Erur9Ew=; b=LUK6bvoalZarG4/10cYHOZVvkyeNt2lEqUWhowXbLcD+qkR3buH7JhF5yXgOoCVdBp O7OXVaFRdd4eOy/68sUTshux6qDWvyS/aGhCNkl/WOh4rmEr5KUVje9avyZkK125rG+V 9Z8Gg27p8EeCJWVHvOfGNHxCqvRTKbPJvx+jT1y1f5nFBiw0s8vHuw+cS+2jturqdUpq qcA5aUtiWY/6Mv67KNy8Xnxo27MpcB5VavrSk0QmUPf3LiWtAng66627xFQD9+lDAZVu s7TsegWqJoTM17tKQ1enaiBmypeI52CwuresDKCbQBbTv/NyLCzn3CzLtV+QUJnl03oB pfuQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=content-transfer-encoding:in-reply-to:from:references:cc:to :content-language:subject:user-agent:mime-version:date:message-id :x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=MYiaRsw3d498ajPipBA6kI+35MHXcbys3QG+Erur9Ew=; b=bLRhTsjRUae82mZtuag4D64XwI9b9AVUFbIyA6pTihMN3AzojBUd8QydRLAjwWuqxs FOZBI3cUs8eTaCTEcMhq1kImCj4mLCXbwu6cHDNei+pI+TpqPuTQTwT4bxvi5xJ6/5Ef URJpqZfA5lwNLPQb3Ge1O9bKzwE7vspEUnvlNEQ6wUsT6rXKD9WcHrW9rPz5T+ZFS4hF sMSOYJXyG1+axJg5t1OVBvQLDXzSF+pNXftcpwr9t7G7fNW/zh+Ue1c9k0lyi+52qrF3 jRx2aYFnal16iTxJ//lRpzU+OT5uhOcTJueEK4r2rE85Fqm+t5Z9sPSdNB2p5YKCzSKN 906A== X-Gm-Message-State: ACrzQf13dyeK5KQWfMVcjIPNr2JF/yVRp9eZIIGTHW5c6fKGXugoZZhl ivEj6weQvA6kLpH+xIn4D4XkbfXWfyqAoUXb X-Google-Smtp-Source: AMsMyM7jZWw7vWX/+/eoA9x8P2bxtDrEuqS7UMYLzznoyZoJS7iPnhqACqXDq+aEm8Hrq04fjOECIw== X-Received: by 2002:adf:c601:0:b0:230:7cfa:b3fe with SMTP id n1-20020adfc601000000b002307cfab3femr7725303wrg.344.1666255155871; Thu, 20 Oct 2022 01:39:15 -0700 (PDT) Received: from [10.176.68.61] ([192.19.148.250]) by smtp.gmail.com with ESMTPSA id q10-20020adff94a000000b00225307f43fbsm15987886wrr.44.2022.10.20.01.39.15 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Thu, 20 Oct 2022 01:39:15 -0700 (PDT) Message-ID: <649de84e-6f9a-5c6b-9a94-a7c6462abd1f@gmail.com> Date: Thu, 20 Oct 2022 10:39:14 +0200 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:91.0) Gecko/20100101 Thunderbird/91.13.1 Subject: Re: [PATCH] brcmfmac: Fixes potential buffer overflow in 'brcmf_fweh_event_worker' Content-Language: en-US To: Dokyung Song , linux-wireless@vger.kernel.org Cc: Jisoo Jang , Minsuk Kang References: <20221020014907.GA338234@laguna> From: Arend Van Spriel In-Reply-To: <20221020014907.GA338234@laguna> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-wireless@vger.kernel.org On 10/20/2022 3:49 AM, Dokyung Song wrote: > This patch fixes an intra-object buffer overflow in brcmfmac that occurs > when the device provides a 'bsscfgidx' equal to or greater than the > buffer size. The patch adds a check that leads to a safe failure if that > is the case. > > Found by a modified version of syzkaller. > > UBSAN: array-index-out-of-bounds in drivers/net/wireless/broadcom/brcm80211/brcmfmac/fweh.c > index 52 is out of range for type 'brcmf_if *[16]' > CPU: 0 PID: 1898 Comm: kworker/0:2 Tainted: G O 5.14.0+ #132 [...] > Kernel panic - not syncing: Fatal exception > > Reported-by: Dokyung Song > Reported-by: Jisoo Jang > Reported-by: Minsuk Kang Not sure what the rules are for using 'Reported-by' tag, but it looks a bit odd. I leave it to the wireless maintainer. Reviewed-by: Arend van Spriel > Signed-off-by: Dokyung Song > --- > drivers/net/wireless/broadcom/brcm80211/brcmfmac/fweh.c | 9 +++++++-- > 1 file changed, 7 insertions(+), 2 deletions(-) > > diff --git a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/fweh.c b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/fweh.c > index bc3f4e4edcdf..e035e9c5a1fa 100644 > --- a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/fweh.c > +++ b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/fweh.c > @@ -255,10 +255,15 @@ static void brcmf_fweh_event_worker(struct work_struct *work) > goto event_free; > } > > - if (event->code == BRCMF_E_TDLS_PEER_EVENT) > + if (event->code == BRCMF_E_TDLS_PEER_EVENT) { > ifp = drvr->iflist[0]; > - else > + } else { > + if (emsg.bsscfgidx >= BRCMF_MAX_IFS) { > + bphy_err(drvr, "invalid bsscfg index: %u\n", emsg.bsscfgidx); > + goto event_free; > + } probably better to do the validation before any other handling. So right after converting the event message at line 245 https://elixir.bootlin.com/linux/latest/source/drivers/net/wireless/broadcom/brcm80211/brcmfmac/fweh.c#L245 > ifp = drvr->iflist[emsg.bsscfgidx]; > + } > err = brcmf_fweh_call_event_handler(drvr, ifp, event->code, > &emsg, event->data); > if (err) {