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=-19.1 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, USER_AGENT_GIT 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 94157C48BC2 for ; Mon, 21 Jun 2021 16:45:40 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 831646108E for ; Mon, 21 Jun 2021 16:45:40 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232631AbhFUQrx (ORCPT ); Mon, 21 Jun 2021 12:47:53 -0400 Received: from mail.kernel.org ([198.145.29.99]:33868 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233163AbhFUQnR (ORCPT ); Mon, 21 Jun 2021 12:43:17 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 3840D61445; Mon, 21 Jun 2021 16:31:29 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1624293089; bh=G6azULgzfCzqoGEWeSwpKyauIDsk5HwKoz6iDfwBgMs=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=f1pgO8nq0kykThVHWr4aW10Ve0CemcPqelg48oU8SD8dKyk2hmCBpYXsC6HlcOv+D pLiwkagI1LFV7y7X74J1c6mQkG9Epufhpejc/AF/NqUg3PQyIh+p0mvYA47/ChpRMX S8mggN3n3Q1Hji6Qcx8W7pQPrfo2P24xNe6faIK8= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Pavel Skripkin , Bjorn Andersson , "David S. Miller" , Sasha Levin , syzbot+1917d778024161609247@syzkaller.appspotmail.com Subject: [PATCH 5.12 061/178] net: qrtr: fix OOB Read in qrtr_endpoint_post Date: Mon, 21 Jun 2021 18:14:35 +0200 Message-Id: <20210621154924.560861055@linuxfoundation.org> X-Mailer: git-send-email 2.32.0 In-Reply-To: <20210621154921.212599475@linuxfoundation.org> References: <20210621154921.212599475@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: linux-kernel@vger.kernel.org From: Pavel Skripkin [ Upstream commit ad9d24c9429e2159d1e279dc3a83191ccb4daf1d ] 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 Signed-off-by: David S. Miller Signed-off-by: Sasha Levin --- 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 1e4fb568fa84..24f10bf7d8a3 100644 --- a/net/qrtr/qrtr.c +++ b/net/qrtr/qrtr.c @@ -435,7 +435,7 @@ 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; -- 2.30.2