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=-15.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=ham 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 EB3DEC2B9F4 for ; Mon, 14 Jun 2021 15:58:56 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id BD9DC61245 for ; Mon, 14 Jun 2021 15:58:56 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233135AbhFNQA6 (ORCPT ); Mon, 14 Jun 2021 12:00:58 -0400 Received: from mail-oi1-f171.google.com ([209.85.167.171]:36699 "EHLO mail-oi1-f171.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233006AbhFNQA6 (ORCPT ); Mon, 14 Jun 2021 12:00:58 -0400 Received: by mail-oi1-f171.google.com with SMTP id r16so14443852oiw.3 for ; Mon, 14 Jun 2021 08:58:47 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to; bh=94iIJWdnufdLWAXQdWLP9tyvdsiAcGYzNeNNwgwJVDg=; b=IqTXgIT+Cl8Wo9ps3519Xaw5nP9M00zvUCAESiMwX2JltCyvmClzopQPyd/gV29uYU AJgedo2DeLfn5nx9CzA4y/kbAtunlZgY1BjhfVljwo74gbDn4JxvRLFLMLgZ3hdatGLG QZmBMuqmSDIvKsmaDy9i4xx4pSHccwXsHrWZPbol306BOxH2iV6qgRLIEoMHSalJ7KM2 J6mB8jxB9tWItV6w9t7QsTnWQy9is97/eaCy2kbWhE6esMZx/PmnnHamYfcDh0aOzUjk d/PRWj0+VPRespIVqfRDKmIQxAyEgdwEL+Qil9EoLlOy/gQuazuROa7qaJO/kFebP+LD qpRw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to; bh=94iIJWdnufdLWAXQdWLP9tyvdsiAcGYzNeNNwgwJVDg=; b=jX2AfxHIvi6f6zBLJgCzbJgj0g/l4LN9GrjpzcMa+Nhnul/P/hzII5rPPzTTH2ruSj A/l6lHVVCisoXNenFzUgQ1m/SVYCVnUFkM0dRIuRt4ekbbcqGTSGqLvWDJk3Tm9cneFC fd9Rw70k14jFBNhJm8u14FnxUcXH340+WjGx9Y6EsQMP5Nk0O/g8XaAzPbe2RYwwD+Nx DKc/Cxsa7mBGaIOYy6zGJvkOd/bIP1dP3+JUXNCiTqBns6MZz3HaBSc8WNcSjAOGdI/p vXY4zDUpsjk0oUO4NsoLSXQf3qeP9H6bA+j3g8nnB51VDX40Mz9fzavmvK8t5VNQrLJi ATpQ== X-Gm-Message-State: AOAM530cD8XI1xgUm4dMFJDydgSeq6msC7hplKXihlE9Hm5JQ7LkvNl0 KtrSybUp8M3D0iUO36HZbVleQw== X-Google-Smtp-Source: ABdhPJxl00X8N39+K/fL/lQtc3Y9cNUIlK/sTxo5x7SmvJMEDgs+x/NARXztwoamyE8n6s/bhqicGA== X-Received: by 2002:aca:b609:: with SMTP id g9mr22032540oif.141.1623686267640; Mon, 14 Jun 2021 08:57:47 -0700 (PDT) Received: from yoga (104-57-184-186.lightspeed.austtx.sbcglobal.net. [104.57.184.186]) by smtp.gmail.com with ESMTPSA id c205sm3137575oob.38.2021.06.14.08.57.46 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 14 Jun 2021 08:57:47 -0700 (PDT) Date: Mon, 14 Jun 2021 10:57:45 -0500 From: Bjorn Andersson To: Pavel Skripkin Cc: mani@kernel.org, davem@davemloft.net, linux-arm-msm@vger.kernel.org, netdev@vger.kernel.org, linux-kernel@vger.kernel.org, syzbot+1917d778024161609247@syzkaller.appspotmail.com Subject: Re: [PATCH] net: qrtr: fix OOB Read in qrtr_endpoint_post Message-ID: References: <20210614120650.2731-1-paskripkin@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20210614120650.2731-1-paskripkin@gmail.com> Precedence: bulk List-ID: X-Mailing-List: linux-arm-msm@vger.kernel.org On Mon 14 Jun 07:06 CDT 2021, Pavel Skripkin wrote: > Syzbot reported slab-out-of-bounds Read in > qrtr_endpoint_post. The problem was in wrong > _size_ type: > > if (len != ALIGN(size, 4) + hdrlen) > goto err; > > If size from qrtr_hdr is 4294967293 (0xfffffffd), the result of > ALIGN(size, 4) will be 0. In case of len == hdrlen and size == 4294967293 > in header this check won't fail and > > skb_put_data(skb, data + hdrlen, size); > > will read out of bound from data, which is hdrlen allocated block. > > Fixes: 194ccc88297a ("net: qrtr: Support decoding incoming v2 packets") > Reported-and-tested-by: syzbot+1917d778024161609247@syzkaller.appspotmail.com > Signed-off-by: Pavel Skripkin Reviewed-by: Bjorn Andersson Regards, Bjorn > --- > net/qrtr/qrtr.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/net/qrtr/qrtr.c b/net/qrtr/qrtr.c > index c0477bec09bd..f2efaa4225f9 100644 > --- a/net/qrtr/qrtr.c > +++ b/net/qrtr/qrtr.c > @@ -436,7 +436,7 @@ int qrtr_endpoint_post(struct qrtr_endpoint *ep, const void *data, size_t len) > struct qrtr_sock *ipc; > struct sk_buff *skb; > struct qrtr_cb *cb; > - unsigned int size; > + size_t size; > unsigned int ver; > size_t hdrlen; > > -- > 2.32.0 >