Re: [Qemu-devel] [PATCH v3 4/4] vga: Fix divide-by-zero in vga_update_text

[Paolo Bonzini]

Il 12/06/2014 12:43, Gerd Hoffmann ha scritto:
> That doesn't fix the reported issue.  It's "width" which Coverity thinks
> might be zero, not cursor_offset.  And cursor_offset being zero is
> perfectly fine, happens when the cursor is in the upper left corner.
>
> I have no idea why Coverity thinks width can be zero there.  Line 2047:
>
>         width = (s->cr[VGA_CRTC_H_DISP] + 1);
>
> (where cr is uint8_t).  Hmm, maybe for the wraparound case (i.e.
> s->cr[VGA_CRTC_H_DISP] == 0xff)?

Not even that, the result is 0x100, math is done on the "int" data type.

In fact I don't even see this defect on scan.coverity.com.

Paolo