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Fix CVE-2017-8379:
https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2017-8379
Patch copied from upstream source repository:
http://git.qemu.org/?p=qemu.git;a=commitdiff;h=fa18f36a461984eae50ab957e47ec78dae3c14fc
From fa18f36a461984eae50ab957e47ec78dae3c14fc Mon Sep 17 00:00:00 2001
From: Gerd Hoffmann <kraxel@redhat.com>
Date: Fri, 28 Apr 2017 10:42:37 +0200
Subject: [PATCH] input: limit kbd queue depth
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 <ppandit@redhat.com>
Cc: Huawei PSIRT <PSIRT@huawei.com>
Reported-by: jiangxin1@huawei.com
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Message-id: 20170428084237.23960-1-kraxel@redhat.com
---
ui/input.c | 14 +++++++++++---
1 file changed, 11 insertions(+), 3 deletions(-)
diff --git a/ui/input.c b/ui/input.c
index ed88cda6d6..fb1f404095 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)
--
2.13.0
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