958e1b
From 9aeb00acc02f49c754f0bbde5894b45b41407f63 Mon Sep 17 00:00:00 2001
958e1b
From: Gerd Hoffmann <kraxel@redhat.com>
958e1b
Date: Tue, 18 Nov 2014 11:58:56 +0100
958e1b
Subject: [PATCH 33/41] vnc: sanitize bits_per_pixel from the client
958e1b
958e1b
Message-id: <1416311936-5001-2-git-send-email-kraxel@redhat.com>
958e1b
Patchwork-id: 62424
958e1b
O-Subject: [RHEL-7.1 qemu-kvm PATCH 1/1] vnc: sanitize bits_per_pixel from the client
958e1b
Bugzilla: 1157645
958e1b
RH-Acked-by: Laszlo Ersek <lersek@redhat.com>
958e1b
RH-Acked-by: Markus Armbruster <armbru@redhat.com>
958e1b
RH-Acked-by: Dr. David Alan Gilbert (git) <dgilbert@redhat.com>
958e1b
958e1b
From: Petr Matousek <pmatouse@redhat.com>
958e1b
958e1b
bits_per_pixel that are less than 8 could result in accessing
958e1b
non-initialized buffers later in the code due to the expectation
958e1b
that bytes_per_pixel value that is used to initialize these buffers is
958e1b
never zero.
958e1b
958e1b
To fix this check that bits_per_pixel from the client is one of the
958e1b
values that the rfb protocol specification allows.
958e1b
958e1b
This is CVE-2014-7815.
958e1b
958e1b
Signed-off-by: Petr Matousek <pmatouse@redhat.com>
958e1b
958e1b
[ kraxel: apply codestyle fix ]
958e1b
958e1b
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
958e1b
(cherry picked from commit e6908bfe8e07f2b452e78e677da1b45b1c0f6829)
958e1b
Signed-off-by: Miroslav Rezanina <mrezanin@redhat.com>
958e1b
---
958e1b
 ui/vnc.c | 10 ++++++++++
958e1b
 1 file changed, 10 insertions(+)
958e1b
958e1b
diff --git a/ui/vnc.c b/ui/vnc.c
958e1b
index 3726352..a0e2d33 100644
958e1b
--- a/ui/vnc.c
958e1b
+++ b/ui/vnc.c
958e1b
@@ -2024,6 +2024,16 @@ static void set_pixel_format(VncState *vs,
958e1b
         return;
958e1b
     }
958e1b
 
958e1b
+    switch (bits_per_pixel) {
958e1b
+    case 8:
958e1b
+    case 16:
958e1b
+    case 32:
958e1b
+        break;
958e1b
+    default:
958e1b
+        vnc_client_error(vs);
958e1b
+        return;
958e1b
+    }
958e1b
+
958e1b
     vs->client_pf.rmax = red_max;
958e1b
     vs->client_pf.rbits = hweight_long(red_max);
958e1b
     vs->client_pf.rshift = red_shift;
958e1b
-- 
958e1b
1.8.3.1
958e1b