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*From*: 	P J P

*Subject*: 	[Qemu-devel] [PATCH] display: vga: add check to limit

display width

*Date*: 	Tue, 26 Apr 2016 13:37:38 +0530

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From: Prasad J Pandit <address@hidden>

In vga_draw_graphic, display width could exceed the maximum

range of VBE_DISPI_MAX_XRES(16000). This could lead to possible

integer overflows. Add check to avoid it.

Reported-by: Zuozhi Fzz <address@hidden>

Signed-off-by: Prasad J Pandit <address@hidden>

---

 tools/qemu-xen/hw/display/vga.c | 3 +++

 1 file changed, 3 insertions(+)

diff --git a/tools/qemu-xen/hw/display/vga.c b/tools/qemu-xen/hw/display/vga.c

index 9f68394..1a66291 100644

--- a/tools/qemu-xen/hw/display/vga.c

+++ b/tools/qemu-xen/hw/display/vga.c

@@ -1478,6 +1478,9 @@ static void vga_draw_graphic(VGACommonState *s, int full_update)

             disp_width <<= 1;

         }

     }

+    if (disp_width > VBE_DISPI_MAX_XRES) {

+        disp_width = VBE_DISPI_MAX_XRES;

+    }

     depth = s->get_bpp(s);

-- 

2.5.5