From 1ca0e710f8115e1bc0406a8799de71fb0b3def13 Mon Sep 17 00:00:00 2001 From: Marc-André Lureau Date: Tue, 17 Jul 2012 19:09:18 +0200 Subject: Run-time check monitor per display count <= 256 Limit range of monitors, to avoid potential crashes lead by invalid received MonitorConfig values (could be misconfigured or misbehaving guest) This is a a client-side implementation limitation. Eventually, the range could be inscreased (or unlimited == 0) in the future... --- gtk/channel-display.c | 16 +++++++++++++++- 1 file changed, 15 insertions(+), 1 deletion(-) diff --git a/gtk/channel-display.c b/gtk/channel-display.c index d77447a..72d2c12 100644 --- a/gtk/channel-display.c +++ b/gtk/channel-display.c @@ -59,6 +59,8 @@ #define SPICE_DISPLAY_CHANNEL_GET_PRIVATE(obj) \ (G_TYPE_INSTANCE_GET_PRIVATE((obj), SPICE_TYPE_DISPLAY_CHANNEL, SpiceDisplayChannelPrivate)) +#define MONITORS_MAX 256 + struct _SpiceDisplayChannelPrivate { Ring surfaces; display_cache *images; @@ -275,7 +277,7 @@ static void spice_display_channel_class_init(SpiceDisplayChannelClass *klass) g_param_spec_uint("monitors-max", "Max display monitors", "The current maximum number of monitors", - 1, G_MAXINT16, 1, + 1, MONITORS_MAX, 1, G_PARAM_READABLE | G_PARAM_STATIC_STRINGS)); @@ -1493,6 +1495,8 @@ static void display_handle_surface_destroy(SpiceChannel *channel, SpiceMsgIn *in free(surface); } +#define CLAMP_CHECK(x, low, high) (((x) > (high)) ? TRUE : (((x) < (low)) ? TRUE : FALSE)) + /* coroutine context */ static void display_handle_monitors_config(SpiceChannel *channel, SpiceMsgIn *in) { @@ -1506,6 +1510,16 @@ static void display_handle_monitors_config(SpiceChannel *channel, SpiceMsgIn *in SPICE_DEBUG("monitors config: n: %d/%d", config->count, config->max_allowed); c->monitors_max = config->max_allowed; + if (CLAMP_CHECK(c->monitors_max, 1, MONITORS_MAX)) { + g_warning("MonitorConfig max_allowed is not within permitted range, clamping"); + c->monitors_max = CLAMP(c->monitors_max, 1, MONITORS_MAX); + } + + if (CLAMP_CHECK(config->count, 1, c->monitors_max)) { + g_warning("MonitorConfig count is not within permitted range, clamping"); + config->count = CLAMP(config->count, 1, c->monitors_max); + } + c->monitors = g_array_set_size(c->monitors, config->count); for (i = 0; i < config->count; i++) { -- cgit v1.2.3