From e6908bfe8e07f2b452e78e677da1b45b1c0f6829 Mon Sep 17 00:00:00 2001 From: Petr Matousek Date: Mon, 27 Oct 2014 12:41:44 +0100 Subject: vnc: sanitize bits_per_pixel from the client bits_per_pixel that are less than 8 could result in accessing non-initialized buffers later in the code due to the expectation that bytes_per_pixel value that is used to initialize these buffers is never zero. To fix this check that bits_per_pixel from the client is one of the values that the rfb protocol specification allows. This is CVE-2014-7815. Signed-off-by: Petr Matousek [ kraxel: apply codestyle fix ] Signed-off-by: Gerd Hoffmann --- ui/vnc.c | 10 ++++++++++ 1 file changed, 10 insertions(+) (limited to 'ui') diff --git a/ui/vnc.c b/ui/vnc.c index 0fe6eff..8bca597 100644 --- a/ui/vnc.c +++ b/ui/vnc.c @@ -2026,6 +2026,16 @@ static void set_pixel_format(VncState *vs, return; } + switch (bits_per_pixel) { + case 8: + case 16: + case 32: + break; + default: + vnc_client_error(vs); + return; + } + vs->client_pf.rmax = red_max; vs->client_pf.rbits = hweight_long(red_max); vs->client_pf.rshift = red_shift; -- cgit v1.1 From 9d6b20704734fe1ab789400806ebd54f579d50a2 Mon Sep 17 00:00:00 2001 From: ChenLiang Date: Mon, 29 Sep 2014 15:00:40 +0800 Subject: vnc: return directly if no vnc client connected graphic_hw_update and vnc_refresh_server_surface aren't need to do when no vnc client connected. It can reduce lock contention, because vnc_refresh will hold global big lock two millisecond every three seconds. Signed-off-by: ChenLiang Signed-off-by: Gonglei Signed-off-by: Gerd Hoffmann --- ui/vnc.c | 10 +++++----- 1 file changed, 5 insertions(+), 5 deletions(-) (limited to 'ui') diff --git a/ui/vnc.c b/ui/vnc.c index 8bca597..5707015 100644 --- a/ui/vnc.c +++ b/ui/vnc.c @@ -2778,6 +2778,11 @@ static void vnc_refresh(DisplayChangeListener *dcl) VncState *vs, *vn; int has_dirty, rects = 0; + if (QTAILQ_EMPTY(&vd->clients)) { + update_displaychangelistener(&vd->dcl, VNC_REFRESH_INTERVAL_MAX); + return; + } + graphic_hw_update(NULL); if (vnc_trylock_display(vd)) { @@ -2793,11 +2798,6 @@ static void vnc_refresh(DisplayChangeListener *dcl) /* vs might be free()ed here */ } - if (QTAILQ_EMPTY(&vd->clients)) { - update_displaychangelistener(&vd->dcl, VNC_REFRESH_INTERVAL_MAX); - return; - } - if (has_dirty && rects) { vd->dcl.update_interval /= 2; if (vd->dcl.update_interval < VNC_REFRESH_INTERVAL_BASE) { -- cgit v1.1