[SeaBIOS] [PATCH v2 3/6] acpi_extract: fix off-by-one

[Michael S. Tsirkin]

On Thu, Aug 02, 2012 at 03:07:23PM +0200, Paolo Bonzini wrote:
> Single-byte package length values do use bits 4-5, and this will
> happen with the PCI hotplug devices.  pkglenbytes has not yet been
> decremented, so multi-byte values are detected with pkglenbytes > 1.
> 
> Signed-off-by: Paolo Bonzini <pbonzini at redhat.com>

Acked-by: Michael S. Tsirkin <mst at redhat.com>

> ---
>  tools/acpi_extract.py |    2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/tools/acpi_extract.py b/tools/acpi_extract.py
> index 167a322..81fa4aa 100755
> --- a/tools/acpi_extract.py
> +++ b/tools/acpi_extract.py
> @@ -93,7 +93,7 @@ def aml_pkglen(offset):
>      pkglenbytes = aml_pkglen_bytes(offset)
>      pkglen = aml[offset] & 0x3F
>      # If multibyte, first nibble only uses bits 0-3
> -    if ((pkglenbytes > 0) and (pkglen & 0x30)):
> +    if ((pkglenbytes > 1) and (pkglen & 0x30)):
>          die("PkgLen bytes 0x%x but first nibble 0x%x expected 0x0X" %
>              (pkglen, pkglen))
>      offset += 1
> -- 
> 1.7.10.4
>