From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:49079) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1dmUCx-0001u8-1M for qemu-devel@nongnu.org; Mon, 28 Aug 2017 20:16:44 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1dmUCt-0006JE-0f for qemu-devel@nongnu.org; Mon, 28 Aug 2017 20:16:43 -0400 Received: from mx0b-001b2d01.pphosted.com ([148.163.158.5]:35504 helo=mx0a-001b2d01.pphosted.com) by eggs.gnu.org with esmtps (TLS1.0:RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1dmUCs-0006Id-Q0 for qemu-devel@nongnu.org; Mon, 28 Aug 2017 20:16:38 -0400 Received: from pps.filterd (m0098413.ppops.net [127.0.0.1]) by mx0b-001b2d01.pphosted.com (8.16.0.21/8.16.0.21) with SMTP id v7T0E8DR017766 for ; Mon, 28 Aug 2017 20:16:38 -0400 Received: from e13.ny.us.ibm.com (e13.ny.us.ibm.com [129.33.205.203]) by mx0b-001b2d01.pphosted.com with ESMTP id 2cmub2wwdp-1 (version=TLSv1.2 cipher=AES256-SHA bits=256 verify=NOT) for ; Mon, 28 Aug 2017 20:16:38 -0400 Received: from localhost by e13.ny.us.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted for from ; Mon, 28 Aug 2017 20:16:37 -0400 From: Michael Roth Date: Mon, 28 Aug 2017 19:14:47 -0500 In-Reply-To: <1503965694-10794-1-git-send-email-mdroth@linux.vnet.ibm.com> References: <1503965694-10794-1-git-send-email-mdroth@linux.vnet.ibm.com> Message-Id: <1503965694-10794-73-git-send-email-mdroth@linux.vnet.ibm.com> Subject: [Qemu-devel] [PATCH 72/79] input: limit kbd queue depth List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-devel@nongnu.org Cc: qemu-stable@nongnu.org, Gerd Hoffmann , P J P , Huawei PSIRT From: Gerd Hoffmann Apply a limit to the number of items we accept into the keyboard queue. Impact: Without this limit vnc clients can exhaust host memory by sending keyboard events faster than qemu feeds them to the guest. Fixes: CVE-2017-8379 Cc: P J P Cc: Huawei PSIRT Reported-by: jiangxin1@huawei.com Signed-off-by: Gerd Hoffmann Message-id: 20170428084237.23960-1-kraxel@redhat.com (cherry picked from commit fa18f36a461984eae50ab957e47ec78dae3c14fc) Signed-off-by: Michael Roth --- ui/input.c | 14 +++++++++++--- 1 file changed, 11 insertions(+), 3 deletions(-) diff --git a/ui/input.c b/ui/input.c index ed88cda..fb1f404 100644 --- a/ui/input.c +++ b/ui/input.c @@ -41,6 +41,8 @@ static QTAILQ_HEAD(QemuInputEventQueueHead, QemuInputEventQueue) kbd_queue = QTAILQ_HEAD_INITIALIZER(kbd_queue); static QEMUTimer *kbd_timer; static uint32_t kbd_default_delay_ms = 10; +static uint32_t queue_count; +static uint32_t queue_limit = 1024; QemuInputHandlerState *qemu_input_handler_register(DeviceState *dev, QemuInputHandler *handler) @@ -268,6 +270,7 @@ static void qemu_input_queue_process(void *opaque) break; } QTAILQ_REMOVE(queue, item, node); + queue_count--; g_free(item); } } @@ -282,6 +285,7 @@ static void qemu_input_queue_delay(struct QemuInputEventQueueHead *queue, item->delay_ms = delay_ms; item->timer = timer; QTAILQ_INSERT_TAIL(queue, item, node); + queue_count++; if (start_timer) { timer_mod(item->timer, qemu_clock_get_ms(QEMU_CLOCK_VIRTUAL) @@ -298,6 +302,7 @@ static void qemu_input_queue_event(struct QemuInputEventQueueHead *queue, item->src = src; item->evt = evt; QTAILQ_INSERT_TAIL(queue, item, node); + queue_count++; } static void qemu_input_queue_sync(struct QemuInputEventQueueHead *queue) @@ -306,6 +311,7 @@ static void qemu_input_queue_sync(struct QemuInputEventQueueHead *queue) item->type = QEMU_INPUT_QUEUE_SYNC; QTAILQ_INSERT_TAIL(queue, item, node); + queue_count++; } void qemu_input_event_send_impl(QemuConsole *src, InputEvent *evt) @@ -381,7 +387,7 @@ void qemu_input_event_send_key(QemuConsole *src, KeyValue *key, bool down) qemu_input_event_send(src, evt); qemu_input_event_sync(); qapi_free_InputEvent(evt); - } else { + } else if (queue_count < queue_limit) { qemu_input_queue_event(&kbd_queue, src, evt); qemu_input_queue_sync(&kbd_queue); } @@ -409,8 +415,10 @@ void qemu_input_event_send_key_delay(uint32_t delay_ms) kbd_timer = timer_new_ms(QEMU_CLOCK_VIRTUAL, qemu_input_queue_process, &kbd_queue); } - qemu_input_queue_delay(&kbd_queue, kbd_timer, - delay_ms ? delay_ms : kbd_default_delay_ms); + if (queue_count < queue_limit) { + qemu_input_queue_delay(&kbd_queue, kbd_timer, + delay_ms ? delay_ms : kbd_default_delay_ms); + } } InputEvent *qemu_input_event_new_btn(InputButton btn, bool down) -- 2.7.4