From 9aeb00acc02f49c754f0bbde5894b45b41407f63 Mon Sep 17 00:00:00 2001 From: Gerd Hoffmann Date: Tue, 18 Nov 2014 11:58:56 +0100 Subject: [PATCH 33/41] vnc: sanitize bits_per_pixel from the client Message-id: <1416311936-5001-2-git-send-email-kraxel@redhat.com> Patchwork-id: 62424 O-Subject: [RHEL-7.1 qemu-kvm PATCH 1/1] vnc: sanitize bits_per_pixel from the client Bugzilla: 1157645 RH-Acked-by: Laszlo Ersek RH-Acked-by: Markus Armbruster RH-Acked-by: Dr. David Alan Gilbert (git) From: Petr Matousek 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 (cherry picked from commit e6908bfe8e07f2b452e78e677da1b45b1c0f6829) Signed-off-by: Miroslav Rezanina --- ui/vnc.c | 10 ++++++++++ 1 file changed, 10 insertions(+) diff --git a/ui/vnc.c b/ui/vnc.c index 3726352..a0e2d33 100644 --- a/ui/vnc.c +++ b/ui/vnc.c @@ -2024,6 +2024,16 @@ 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; -- 1.8.3.1