From patchwork Tue Nov 22 18:46:05 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Stefano Stabellini X-Patchwork-Id: 9441927 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id B51AF600BA for ; Tue, 22 Nov 2016 18:48:30 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id A99C8285B4 for ; Tue, 22 Nov 2016 18:48:30 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 9D8DB284AE; Tue, 22 Nov 2016 18:48:30 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-4.2 required=2.0 tests=BAYES_00, RCVD_IN_DNSWL_MED autolearn=ham version=3.3.1 Received: from lists.xenproject.org (lists.xenproject.org [192.237.175.120]) (using TLSv1.2 with cipher AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.wl.linuxfoundation.org (Postfix) with ESMTPS id 262EE284AE for ; Tue, 22 Nov 2016 18:48:30 +0000 (UTC) Received: from localhost ([127.0.0.1] helo=lists.xenproject.org) by lists.xenproject.org with esmtp (Exim 4.84_2) (envelope-from ) id 1c9G5F-00024l-Hj; Tue, 22 Nov 2016 18:46:21 +0000 Received: from mail6.bemta6.messagelabs.com ([193.109.254.103]) by lists.xenproject.org with esmtp (Exim 4.84_2) (envelope-from ) id 1c9G5E-00024Y-Cq for xen-devel@lists.xenproject.org; Tue, 22 Nov 2016 18:46:20 +0000 Received: from [193.109.254.147] by server-4.bemta-6.messagelabs.com id 9E/4B-28568-B7294385; Tue, 22 Nov 2016 18:46:19 +0000 X-Brightmail-Tracker: H4sIAAAAAAAAA+NgFvrDLMWRWlGSWpSXmKPExsVybKJsh271JJM Ig1cz+S2+b5nM5MDocfjDFZYAxijWzLyk/IoE1oyrNzpZC7qEKq4cf83YwDift4uRi0NIYCqj xNRZl5ghnO1MEqen3WTvYuTkYBMwlPj7ZBMbiC0iICZxevc0JpAiZoEnjBKtffMZQRLCAtoSH b8ms4DYLAKqEr9fHQJr4BVwkzjx8TqYLSEgJ3Hy2GRWEJtTwEeia8IKMFtIwFvi0fp2VoiaDI l5PXOgbC+JRTcuQdlqElfPbWKewMi3gJFhFaNGcWpRWWqRrqG5XlJRZnpGSW5iZo6uoYGZXm5 qcXFiempOYlKxXnJ+7iZGYKgwAMEOxtsbAw4xSnIwKYnyHl5qFCHEl5SfUpmRWJwRX1Sak1p8 iFGGg0NJgvfFBJMIIcGi1PTUirTMHGDQwqQlOHiURHgnTgRK8xYXJOYWZ6ZDpE4xKkqJ864HS QiAJDJK8+DaYJFyiVFWSpiXEegQIZ6C1KLczBJU+VeM4hyMSsK880Cm8GTmlcBNfwW0mAlose Q3Y5DFJYkIKakGxqbgCdOFVhy8ZnX2v9azGZ55D9ZyWbamu2dalDA5Vpk4C1clHUhSXcnNrS9 57se012lXjp9WU1H6+GuLwY9FLDtfBJxeddygvOUqtxCTpVrgRrloPjVefeta2ak7X/8oF8hX nb72YN/6jw/js0W3XG8vcZjMOFVvo/innlMXfC6+XhUx2dFlpRJLcUaioRZzUXEiAGGtNLuPA gAA X-Env-Sender: sstabellini@kernel.org X-Msg-Ref: server-6.tower-27.messagelabs.com!1479840378!73550294!1 X-Originating-IP: [198.145.29.136] X-SpamReason: No, hits=0.0 required=7.0 tests= X-StarScan-Received: X-StarScan-Version: 9.0.16; banners=-,-,- X-VirusChecked: Checked Received: (qmail 3864 invoked from network); 22 Nov 2016 18:46:19 -0000 Received: from mail.kernel.org (HELO mail.kernel.org) (198.145.29.136) by server-6.tower-27.messagelabs.com with DHE-RSA-AES256-GCM-SHA384 encrypted SMTP; 22 Nov 2016 18:46:19 -0000 Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id D493820148; Tue, 22 Nov 2016 18:46:16 +0000 (UTC) Received: from sstabellini-ThinkPad-X260.hsd1.ca.comcast.net (96-82-76-110-static.hfc.comcastbusiness.net [96.82.76.110]) (using TLSv1.2 with cipher AES128-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 538492011B; Tue, 22 Nov 2016 18:46:13 +0000 (UTC) From: Stefano Stabellini To: stefanha@gmail.com Date: Tue, 22 Nov 2016 10:46:05 -0800 Message-Id: <1479840369-19503-1-git-send-email-sstabellini@kernel.org> X-Mailer: git-send-email 1.9.1 In-Reply-To: References: X-Virus-Scanned: ClamAV using ClamSMTP Cc: peter.maydell@linaro.org, sstabellini@kernel.org, Jan Beulich , qemu-devel@nongnu.org, stefanha@redhat.com, anthony.perard@citrix.com, xen-devel@lists.xenproject.org Subject: [Xen-devel] [PULL 1/5] xen: fix ioreq handling X-BeenThere: xen-devel@lists.xen.org X-Mailman-Version: 2.1.18 Precedence: list List-Id: Xen developer discussion List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Errors-To: xen-devel-bounces@lists.xen.org Sender: "Xen-devel" X-Virus-Scanned: ClamAV using ClamSMTP From: Jan Beulich Avoid double fetches and bounds check size to avoid overflowing internal variables. This is CVE-2016-9381 / XSA-197. Reported-by: yanghongke Signed-off-by: Jan Beulich Reviewed-by: Stefano Stabellini Signed-off-by: Stefano Stabellini --- xen-hvm.c | 16 +++++++++++++++- 1 file changed, 15 insertions(+), 1 deletion(-) diff --git a/xen-hvm.c b/xen-hvm.c index 150c7e7..99b8ee8 100644 --- a/xen-hvm.c +++ b/xen-hvm.c @@ -810,6 +810,10 @@ static void cpu_ioreq_pio(ioreq_t *req) trace_cpu_ioreq_pio(req, req->dir, req->df, req->data_is_ptr, req->addr, req->data, req->count, req->size); + if (req->size > sizeof(uint32_t)) { + hw_error("PIO: bad size (%u)", req->size); + } + if (req->dir == IOREQ_READ) { if (!req->data_is_ptr) { req->data = do_inp(req->addr, req->size); @@ -846,6 +850,10 @@ static void cpu_ioreq_move(ioreq_t *req) trace_cpu_ioreq_move(req, req->dir, req->df, req->data_is_ptr, req->addr, req->data, req->count, req->size); + if (req->size > sizeof(req->data)) { + hw_error("MMIO: bad size (%u)", req->size); + } + if (!req->data_is_ptr) { if (req->dir == IOREQ_READ) { for (i = 0; i < req->count; i++) { @@ -1010,11 +1018,13 @@ static int handle_buffered_iopage(XenIOState *state) req.df = 1; req.type = buf_req->type; req.data_is_ptr = 0; + xen_rmb(); qw = (req.size == 8); if (qw) { buf_req = &buf_page->buf_ioreq[(rdptr + 1) % IOREQ_BUFFER_SLOT_NUM]; req.data |= ((uint64_t)buf_req->data) << 32; + xen_rmb(); } handle_ioreq(state, &req); @@ -1045,7 +1055,11 @@ static void cpu_handle_ioreq(void *opaque) handle_buffered_iopage(state); if (req) { - handle_ioreq(state, req); + ioreq_t copy = *req; + + xen_rmb(); + handle_ioreq(state, ©); + req->data = copy.data; if (req->state != STATE_IOREQ_INPROCESS) { fprintf(stderr, "Badness in I/O request ... not in service?!: "