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 6E028C10F0E for ; Mon, 15 Apr 2019 18:48:25 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 3DDEA2087C for ; Mon, 15 Apr 2019 18:48:25 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1555354105; bh=SY+UyONV8wP7f3PvhZP+xucsYBGez/OGqrhjyq/DTAo=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=BavuzkEm5QQM58HLQS3tTwSxFmUNY5GoO0Uk18kZnTTEZZ1XZ4xNHvr8nZCcoOMDI tUu8Vft04ppwVrCYlew8h4/ytFWUqajlAyKbJ/f9IBPiBTFrI5LsqqLQb87ImSM3Qh MoWqLZCOIr1KDL/a3/Qbz6vkjdKM1EeeXO5IbM7s= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729101AbfDOSsS (ORCPT ); Mon, 15 Apr 2019 14:48:18 -0400 Received: from mail.kernel.org ([198.145.29.99]:52112 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729095AbfDOSsQ (ORCPT ); Mon, 15 Apr 2019 14:48:16 -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 13A91218A1; Mon, 15 Apr 2019 18:48:14 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1555354095; bh=SY+UyONV8wP7f3PvhZP+xucsYBGez/OGqrhjyq/DTAo=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=p4L/gzTGb2kvjCxMTT8MXbqFGGNiWzvOg6iWqviL6cTzrpqIwyg+aUlKtb+LtN0UI f4Vc61uPV2h2aJpNhVJ7nGUWdXjgwEDOcSSBZudfGnXkLuwrVK5G828qDe/toXXX0o 30hQtOQusUqxPYn3lgT3ENcQ1MKb10bgr6PTtldQ= 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 4.9 73/76] xen: Prevent buffer overflow in privcmd ioctl Date: Mon, 15 Apr 2019 20:44:37 +0200 Message-Id: <20190415183729.388192500@linuxfoundation.org> X-Mailer: git-send-email 2.21.0 In-Reply-To: <20190415183707.712011689@linuxfoundation.org> References: <20190415183707.712011689@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 @@ -216,6 +216,9 @@ privcmd_call(unsigned call, __HYPERCALL_DECLS; __HYPERCALL_5ARG(a1, a2, a3, a4, a5); + if (call >= PAGE_SIZE / sizeof(hypercall_page[0])) + return -EINVAL; + stac(); asm volatile(CALL_NOSPEC : __HYPERCALL_5PARAM