debian/patches/extra/CVE-2016-7170-vmsvga-correct-bitmap-and-pixmap-size-checks.patch

   1 From 167d97a3def77ee2dbf6e908b0ecbfe2103977db Mon Sep 17 00:00:00 2001
   2 From: Prasad J Pandit <pjp@fedoraproject.org>
   3 Date: Thu, 8 Sep 2016 18:15:54 +0530
   4 Subject: [PATCH] vmsvga: correct bitmap and pixmap size checks
   5
   6 When processing svga command DEFINE_CURSOR in vmsvga_fifo_run,
   7 the computed BITMAP and PIXMAP size are checked against the
   8 'cursor.mask[]' and 'cursor.image[]' array sizes in bytes.
   9 Correct these checks to avoid OOB memory access.
  10
  11 Reported-by: Qinghao Tang <luodalongde@gmail.com>
  12 Reported-by: Li Qiang <liqiang6-s@360.cn>
  13 Signed-off-by: Prasad J Pandit <pjp@fedoraproject.org>
  14 Message-id: 1473338754-15430-1-git-send-email-ppandit@redhat.com
  15 Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
  16 ---
  17  hw/display/vmware_vga.c | 12 +++++++-----
  18  1 file changed, 7 insertions(+), 5 deletions(-)
  19
  20 diff --git a/hw/display/vmware_vga.c b/hw/display/vmware_vga.c
  21 index e51a05e..6599cf0 100644
  22 --- a/hw/display/vmware_vga.c
  23 +++ b/hw/display/vmware_vga.c
  24 @@ -676,11 +676,13 @@ static void vmsvga_fifo_run(struct vmsvga_state_s *s)
  25              cursor.bpp = vmsvga_fifo_read(s);
  26
  27              args = SVGA_BITMAP_SIZE(x, y) + SVGA_PIXMAP_SIZE(x, y, cursor.bpp);
  28 -            if (cursor.width > 256 ||
  29 -                cursor.height > 256 ||
  30 -                cursor.bpp > 32 ||
  31 -                SVGA_BITMAP_SIZE(x, y) > sizeof cursor.mask ||
  32 -                SVGA_PIXMAP_SIZE(x, y, cursor.bpp) > sizeof cursor.image) {
  33 +            if (cursor.width > 256
  34 +                || cursor.height > 256
  35 +                || cursor.bpp > 32
  36 +                || SVGA_BITMAP_SIZE(x, y)
  37 +                    > sizeof(cursor.mask) / sizeof(cursor.mask[0])
  38 +                || SVGA_PIXMAP_SIZE(x, y, cursor.bpp)
  39 +                    > sizeof(cursor.image) / sizeof(cursor.image[0])) {
  40                      goto badcmd;
  41              }
  42
  43 --
  44 2.1.4
  45