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=-6.0 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=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 2A919C10F0E for ; Mon, 15 Apr 2019 19:15:34 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id E11852073F for ; Mon, 15 Apr 2019 19:15:33 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1555355734; bh=e2tOFBoU5wYtkPRHkaxNc1B5wnVXy5OOuGbYz/kMnbU=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=2kmjvHj1hyrX52k/tRi4ZNdF6Dp7TVIxUd45M5hC3UMQqr6378yo8FL136EoKT6// 074P+i0URphxkSYOIDjLDwqqyg5q2wSaE7/hlJSLKdcXxsqt5b0P0mikMksp1byaN5 zlnOZRX4l+m5Cpd48DKEFRuJ25PA95gWrmAO1nTM= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731678AbfDOTOB (ORCPT ); Mon, 15 Apr 2019 15:14:01 -0400 Received: from mail.kernel.org ([198.145.29.99]:52058 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1731673AbfDOTOB (ORCPT ); Mon, 15 Apr 2019 15:14:01 -0400 Received: from localhost (83-86-89-107.cable.dynamic.v4.ziggo.nl [83.86.89.107]) (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 1233E218A1; Mon, 15 Apr 2019 19:13:59 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1555355640; bh=e2tOFBoU5wYtkPRHkaxNc1B5wnVXy5OOuGbYz/kMnbU=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=VUQtctVGFVCQweIzf1yveyWSe1CvtDQDW7cNX6LaCUp7Oi9cMWne64qy6Iyh0XrjP d/7DOx6U3DfR7UvmXcQxxAhtYvMRJy/Z446cvmGWYwd67OrxreNX93AsNJsTZ2uYBs NNjfUrgVajEGEhCyeu7a9uRfmqU2jFp8FxFrSISI= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Dan Carpenter , Boris Ostrovsky , Juergen Gross Subject: [PATCH 5.0 097/117] xen: Prevent buffer overflow in privcmd ioctl Date: Mon, 15 Apr 2019 21:01:07 +0200 Message-Id: <20190415183749.748211194@linuxfoundation.org> X-Mailer: git-send-email 2.21.0 In-Reply-To: <20190415183744.887851196@linuxfoundation.org> References: <20190415183744.887851196@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: stable-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Dan Carpenter commit 42d8644bd77dd2d747e004e367cb0c895a606f39 upstream. The "call" variable comes from the user in privcmd_ioctl_hypercall(). It's an offset into the hypercall_page[] which has (PAGE_SIZE / 32) elements. We need to put an upper bound on it to prevent an out of bounds access. Cc: stable@vger.kernel.org Fixes: 1246ae0bb992 ("xen: add variable hypercall caller") Signed-off-by: Dan Carpenter Reviewed-by: Boris Ostrovsky Signed-off-by: Juergen Gross Signed-off-by: Greg Kroah-Hartman --- arch/x86/include/asm/xen/hypercall.h | 3 +++ 1 file changed, 3 insertions(+) --- a/arch/x86/include/asm/xen/hypercall.h +++ b/arch/x86/include/asm/xen/hypercall.h @@ -206,6 +206,9 @@ xen_single_call(unsigned int call, __HYPERCALL_DECLS; __HYPERCALL_5ARG(a1, a2, a3, a4, a5); + if (call >= PAGE_SIZE / sizeof(hypercall_page[0])) + return -EINVAL; + asm volatile(CALL_NOSPEC : __HYPERCALL_5PARAM : [thunk_target] "a" (&hypercall_page[call])