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=-6.1 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT 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 628D5C677D4 for ; Mon, 8 Oct 2018 18:47:56 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 1E359214C4 for ; Mon, 8 Oct 2018 18:47:56 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=kernel.org header.i=@kernel.org header.b="SK+MHcPM" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 1E359214C4 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=linuxfoundation.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731547AbeJICBA (ORCPT ); Mon, 8 Oct 2018 22:01:00 -0400 Received: from mail.kernel.org ([198.145.29.99]:49876 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728239AbeJICA7 (ORCPT ); Mon, 8 Oct 2018 22:00:59 -0400 Received: from localhost (ip-213-127-77-176.ip.prioritytelecom.net [213.127.77.176]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 3F68D204FD; Mon, 8 Oct 2018 18:47:52 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1539024472; bh=2FHM7imDNLwTlUppCa6ZvIYx3O+BSlvO5RCQt+Ly+F4=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=SK+MHcPMv4r+NowG2FWQc3IyhggkGvx/kLqsVD3mdpL+uJAdJ1jciEYZxxmRCV7zc rl3ztdCgJSWXrybZCROL+/vJGJerTep0iIOdhMYAUVlxH1A/XlZGiIBh/QHgyUVhQx u8Cuv26TmM2WDSDeEdugor5LuuGKD8TSA/2nIzcE= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Tushar Dave , Daniel Borkmann , Sasha Levin Subject: [PATCH 4.18 051/168] bpf: Fix bpf_msg_pull_data() Date: Mon, 8 Oct 2018 20:30:31 +0200 Message-Id: <20181008175621.993081117@linuxfoundation.org> X-Mailer: git-send-email 2.19.0 In-Reply-To: <20181008175620.043587728@linuxfoundation.org> References: <20181008175620.043587728@linuxfoundation.org> User-Agent: quilt/0.65 X-stable: review MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 4.18-stable review patch. If anyone has any objections, please let me know. ------------------ From: Tushar Dave [ Upstream commit 9db39f4d4f94b61e4b64b077f6ddb2bdfb533a88 ] Helper bpf_msg_pull_data() mistakenly reuses variable 'offset' while linearizing multiple scatterlist elements. Variable 'offset' is used to find first starting scatterlist element i.e. msg->data = sg_virt(&sg[first_sg]) + start - offset" Use different variable name while linearizing multiple scatterlist elements so that value contained in variable 'offset' won't get overwritten. Fixes: 015632bb30da ("bpf: sk_msg program helper bpf_sk_msg_pull_data") Signed-off-by: Tushar Dave Signed-off-by: Daniel Borkmann Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman --- net/core/filter.c | 7 +++---- 1 file changed, 3 insertions(+), 4 deletions(-) --- a/net/core/filter.c +++ b/net/core/filter.c @@ -2282,7 +2282,7 @@ static const struct bpf_func_proto bpf_m BPF_CALL_4(bpf_msg_pull_data, struct sk_msg_buff *, msg, u32, start, u32, end, u64, flags) { - unsigned int len = 0, offset = 0, copy = 0; + unsigned int len = 0, offset = 0, copy = 0, poffset = 0; int bytes = end - start, bytes_sg_total; struct scatterlist *sg = msg->sg_data; int first_sg, last_sg, i, shift; @@ -2338,16 +2338,15 @@ BPF_CALL_4(bpf_msg_pull_data, if (unlikely(!page)) return -ENOMEM; p = page_address(page); - offset = 0; i = first_sg; do { from = sg_virt(&sg[i]); len = sg[i].length; - to = p + offset; + to = p + poffset; memcpy(to, from, len); - offset += len; + poffset += len; sg[i].length = 0; put_page(sg_page(&sg[i]));