From patchwork Fri Jul 14 14:02:03 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Peter Korsgaard X-Patchwork-Id: 788530 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Received: from silver.osuosl.org (smtp3.osuosl.org [140.211.166.136]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by ozlabs.org (Postfix) with ESMTPS id 3x8DsC6CKnz9s65 for ; Sat, 15 Jul 2017 00:02:23 +1000 (AEST) Authentication-Results: ozlabs.org; dkim=fail reason="signature verification failed" (2048-bit key; unprotected) header.d=gmail.com header.i=@gmail.com header.b="kWV1k3uD"; dkim-atps=neutral Received: from localhost (localhost [127.0.0.1]) by silver.osuosl.org (Postfix) with ESMTP id E529130B01; Fri, 14 Jul 2017 14:02:18 +0000 (UTC) X-Virus-Scanned: amavisd-new at osuosl.org Received: from silver.osuosl.org ([127.0.0.1]) by localhost (.osuosl.org [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id z2roLViA9QOJ; Fri, 14 Jul 2017 14:02:16 +0000 (UTC) Received: from ash.osuosl.org (ash.osuosl.org [140.211.166.34]) by silver.osuosl.org (Postfix) with ESMTP id 9E1B02F52E; Fri, 14 Jul 2017 14:02:16 +0000 (UTC) X-Original-To: buildroot@lists.busybox.net Delivered-To: buildroot@osuosl.org Received: from whitealder.osuosl.org (smtp1.osuosl.org [140.211.166.138]) by ash.osuosl.org (Postfix) with ESMTP id E34D01C40B0 for ; Fri, 14 Jul 2017 14:02:14 +0000 (UTC) Received: from localhost (localhost [127.0.0.1]) by whitealder.osuosl.org (Postfix) with ESMTP id DD5BB890E5 for ; Fri, 14 Jul 2017 14:02:14 +0000 (UTC) X-Virus-Scanned: amavisd-new at osuosl.org Received: from whitealder.osuosl.org ([127.0.0.1]) by localhost (.osuosl.org [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id ESNXyr76mGNv for ; Fri, 14 Jul 2017 14:02:14 +0000 (UTC) X-Greylist: domain auto-whitelisted by SQLgrey-1.7.6 Received: from mail-wr0-f194.google.com (mail-wr0-f194.google.com [209.85.128.194]) by whitealder.osuosl.org (Postfix) with ESMTPS id DADD8890DD for ; Fri, 14 Jul 2017 14:02:13 +0000 (UTC) Received: by mail-wr0-f194.google.com with SMTP id v60so265154wrc.2 for ; Fri, 14 Jul 2017 07:02:13 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=sender:from:to:cc:subject:date:message-id; bh=b53TELMaJEzhX+bB/PERizKqM5ueH9Aq2FzbDjVN1dw=; b=kWV1k3uD8H5IzNCnpoWVlqLK7BVH3UZz9uvlreilX8SKPfe0Yvln27cZNcY2UzclZt kHhvgYIgbRXrPO+NQHej8wydzP4ClRxjVO2HaQ4FTdlcBDIem7gUqvnDiQ/bp6nuMmpN 7voqSUsNjC8s8F0S1IE1zOTDmEfXHD0f/sqlG53Z7C/+7T0m3oMWhtiaiaeVQGwTymLI DH+OWzeXKyWL6XBJ7CFgzLtou0VWi4PrCP1OpfvMV9kPYnFJX6mq8U0/6s76DascULYW A86R7XiKMuKhYFdMi2oE1a1BiU905RFs6s5O4XUh14YK1o132AKP8tKhvAkoBO/ouw/+ vxoA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:sender:from:to:cc:subject:date:message-id; bh=b53TELMaJEzhX+bB/PERizKqM5ueH9Aq2FzbDjVN1dw=; b=K7oJrAtnQoFSKtHhqZaedTex9wcJKEcjtzRxCGf/mTV63ssHwhXvWaUrRSJQ96ep1i XxAQCRhDZt11PcOwqF3YrvCmwUPzZORGJMUrfdH25f7hZ5LZJ6QbR1lWcX1DAn6ior3E MSpmiooiiYiXqHQeZJ4w5m4udsOsYojcnDF9BTXxcXHyWm/BiWev7o9E15A4hWQJYXpr g8wCjXO6BvyNyuV3ywXu1r6jHbJ5zvm5intlilV/qiUpDF5jz/nR1RqB7TkA2dD+eRIY TuLqnux0KzzwRqypiMaDbN16AlsUAMWIMcMFGDR2s+T0nWNuRf2pQiOOimqYyKQgT+zG MwiQ== X-Gm-Message-State: AIVw113mNAkycKKZ7MJD9jMetTfkyXhjOLutAhvSr0JsFatwffydzBg1 cmPO9emlvmNKQ+I8TbQ= X-Received: by 10.223.160.111 with SMTP id l44mr5381399wrl.31.1500040931642; Fri, 14 Jul 2017 07:02:11 -0700 (PDT) Received: from dell.be.48ers.dk ([91.183.172.93]) by smtp.gmail.com with ESMTPSA id p27sm2879641wmf.23.2017.07.14.07.02.10 (version=TLS1_2 cipher=ECDHE-RSA-CHACHA20-POLY1305 bits=256/256); Fri, 14 Jul 2017 07:02:10 -0700 (PDT) Received: from peko by dell.be.48ers.dk with local (Exim 4.88) (envelope-from ) id 1dW1AX-00051b-Vx; Fri, 14 Jul 2017 16:02:10 +0200 From: Peter Korsgaard To: buildroot@buildroot.org, yann.morin.1998@free.fr Date: Fri, 14 Jul 2017 16:02:03 +0200 Message-Id: <20170714140203.19234-1-peter@korsgaard.com> X-Mailer: git-send-email 2.11.0 Subject: [Buildroot] [PATCH] spice: add upstream security fixes for CVE-2017-7506 X-BeenThere: buildroot@busybox.net X-Mailman-Version: 2.1.18-1 Precedence: list List-Id: Discussion and development of buildroot List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Errors-To: buildroot-bounces@busybox.net Sender: "buildroot" Fixes CVE-2017-7506 - Possible buffer overflow via invalid monitor configurations. For more details, see: https://marc.info/?l=oss-security&m=150001782924095 Signed-off-by: Peter Korsgaard --- ...nect-when-receiving-overly-big-ClientMoni.patch | 75 ++++++++++++++++++++++ ...integer-overflows-handling-monitor-config.patch | 31 +++++++++ ...buffer-overflows-handling-monitor-configu.patch | 48 ++++++++++++++ 3 files changed, 154 insertions(+) create mode 100644 package/spice/0004-reds-Disconnect-when-receiving-overly-big-ClientMoni.patch create mode 100644 package/spice/0005-reds-Avoid-integer-overflows-handling-monitor-config.patch create mode 100644 package/spice/0006-reds-Avoid-buffer-overflows-handling-monitor-configu.patch diff --git a/package/spice/0004-reds-Disconnect-when-receiving-overly-big-ClientMoni.patch b/package/spice/0004-reds-Disconnect-when-receiving-overly-big-ClientMoni.patch new file mode 100644 index 0000000000..e454a30100 --- /dev/null +++ b/package/spice/0004-reds-Disconnect-when-receiving-overly-big-ClientMoni.patch @@ -0,0 +1,75 @@ +From f1e7ec03e26ab6b8ca9b7ec060846a5b706a963d Mon Sep 17 00:00:00 2001 +From: Frediano Ziglio +Date: Mon, 15 May 2017 15:57:28 +0100 +Subject: [PATCH 4/6] reds: Disconnect when receiving overly big + ClientMonitorsConfig + +Total message size received from the client was unlimited. There is +a 2kiB size check on individual agent messages, but the MonitorsConfig +message can be split in multiple chunks, and the size of the +non-chunked MonitorsConfig message was never checked. This could easily +lead to memory exhaustion on the host. + +Signed-off-by: Frediano Ziglio +Signed-off-by: Peter Korsgaard +--- + server/reds.c | 25 +++++++++++++++++++++++-- + 1 file changed, 23 insertions(+), 2 deletions(-) + +diff --git a/server/reds.c b/server/reds.c +index f439a366..7be85fdf 100644 +--- a/server/reds.c ++++ b/server/reds.c +@@ -993,19 +993,34 @@ static void reds_client_monitors_config_cleanup(void) + static void reds_on_main_agent_monitors_config( + MainChannelClient *mcc, void *message, size_t size) + { ++ const unsigned int MAX_MONITORS = 256; ++ const unsigned int MAX_MONITOR_CONFIG_SIZE = ++ sizeof(VDAgentMonitorsConfig) + MAX_MONITORS * sizeof(VDAgentMonConfig); ++ + VDAgentMessage *msg_header; + VDAgentMonitorsConfig *monitors_config; + RedsClientMonitorsConfig *cmc = &reds->client_monitors_config; + ++ // limit size of message sent by the client as this can cause a DoS through ++ // memory exhaustion, or potentially some integer overflows ++ if (sizeof(VDAgentMessage) + MAX_MONITOR_CONFIG_SIZE - cmc->buffer_size < size) { ++ goto overflow; ++ } + cmc->buffer_size += size; + cmc->buffer = realloc(cmc->buffer, cmc->buffer_size); + spice_assert(cmc->buffer); + cmc->mcc = mcc; + memcpy(cmc->buffer + cmc->buffer_pos, message, size); + cmc->buffer_pos += size; ++ if (sizeof(VDAgentMessage) > cmc->buffer_size) { ++ spice_debug("not enough data yet. %d", cmc->buffer_size); ++ return; ++ } + msg_header = (VDAgentMessage *)cmc->buffer; +- if (sizeof(VDAgentMessage) > cmc->buffer_size || +- msg_header->size > cmc->buffer_size - sizeof(VDAgentMessage)) { ++ if (msg_header->size > MAX_MONITOR_CONFIG_SIZE) { ++ goto overflow; ++ } ++ if (msg_header->size > cmc->buffer_size - sizeof(VDAgentMessage)) { + spice_debug("not enough data yet. %d", cmc->buffer_size); + return; + } +@@ -1013,6 +1028,12 @@ static void reds_on_main_agent_monitors_config( + spice_debug("%s: %d", __func__, monitors_config->num_of_monitors); + red_dispatcher_client_monitors_config(monitors_config); + reds_client_monitors_config_cleanup(); ++ return; ++ ++overflow: ++ spice_warning("received invalid MonitorsConfig request from client, disconnecting"); ++ red_channel_client_disconnect(main_channel_client_get_base(mcc)); ++ reds_client_monitors_config_cleanup(); + } + + void reds_on_main_agent_data(MainChannelClient *mcc, void *message, size_t size) +-- +2.11.0 + diff --git a/package/spice/0005-reds-Avoid-integer-overflows-handling-monitor-config.patch b/package/spice/0005-reds-Avoid-integer-overflows-handling-monitor-config.patch new file mode 100644 index 0000000000..a4e5a3fa6d --- /dev/null +++ b/package/spice/0005-reds-Avoid-integer-overflows-handling-monitor-config.patch @@ -0,0 +1,31 @@ +From ec6229c79abe05d731953df5f7e9a05ec9f6df79 Mon Sep 17 00:00:00 2001 +From: Frediano Ziglio +Date: Mon, 15 May 2017 15:57:28 +0100 +Subject: [PATCH 5/6] reds: Avoid integer overflows handling monitor + configuration + +Avoid VDAgentMessage::size integer overflows. + +Signed-off-by: Frediano Ziglio +Signed-off-by: Peter Korsgaard +--- + server/reds.c | 3 +++ + 1 file changed, 3 insertions(+) + +diff --git a/server/reds.c b/server/reds.c +index 7be85fdf..e1c8c108 100644 +--- a/server/reds.c ++++ b/server/reds.c +@@ -1024,6 +1024,9 @@ static void reds_on_main_agent_monitors_config( + spice_debug("not enough data yet. %d", cmc->buffer_size); + return; + } ++ if (msg_header->size < sizeof(VDAgentMonitorsConfig)) { ++ goto overflow; ++ } + monitors_config = (VDAgentMonitorsConfig *)(cmc->buffer + sizeof(*msg_header)); + spice_debug("%s: %d", __func__, monitors_config->num_of_monitors); + red_dispatcher_client_monitors_config(monitors_config); +-- +2.11.0 + diff --git a/package/spice/0006-reds-Avoid-buffer-overflows-handling-monitor-configu.patch b/package/spice/0006-reds-Avoid-buffer-overflows-handling-monitor-configu.patch new file mode 100644 index 0000000000..0789fdfb08 --- /dev/null +++ b/package/spice/0006-reds-Avoid-buffer-overflows-handling-monitor-configu.patch @@ -0,0 +1,48 @@ +From a957a90baf2c62d31f3547e56bba7d0e812d2331 Mon Sep 17 00:00:00 2001 +From: Frediano Ziglio +Date: Mon, 15 May 2017 15:57:28 +0100 +Subject: [PATCH 6/6] reds: Avoid buffer overflows handling monitor + configuration + +It was also possible for a malicious client to set +VDAgentMonitorsConfig::num_of_monitors to a number larger +than the actual size of VDAgentMOnitorsConfig::monitors. +This would lead to buffer overflows, which could allow the guest to +read part of the host memory. This might cause write overflows in the +host as well, but controlling the content of such buffers seems +complicated. + +Signed-off-by: Frediano Ziglio +Signed-off-by: Peter Korsgaard +--- + server/reds.c | 7 +++++++ + 1 file changed, 7 insertions(+) + +diff --git a/server/reds.c b/server/reds.c +index e1c8c108..3a42c375 100644 +--- a/server/reds.c ++++ b/server/reds.c +@@ -1000,6 +1000,7 @@ static void reds_on_main_agent_monitors_config( + VDAgentMessage *msg_header; + VDAgentMonitorsConfig *monitors_config; + RedsClientMonitorsConfig *cmc = &reds->client_monitors_config; ++ uint32_t max_monitors; + + // limit size of message sent by the client as this can cause a DoS through + // memory exhaustion, or potentially some integer overflows +@@ -1028,6 +1029,12 @@ static void reds_on_main_agent_monitors_config( + goto overflow; + } + monitors_config = (VDAgentMonitorsConfig *)(cmc->buffer + sizeof(*msg_header)); ++ // limit the monitor number to avoid buffer overflows ++ max_monitors = (msg_header->size - sizeof(VDAgentMonitorsConfig)) / ++ sizeof(VDAgentMonConfig); ++ if (monitors_config->num_of_monitors > max_monitors) { ++ goto overflow; ++ } + spice_debug("%s: %d", __func__, monitors_config->num_of_monitors); + red_dispatcher_client_monitors_config(monitors_config); + reds_client_monitors_config_cleanup(); +-- +2.11.0 +