Re: [PATCH] xc_inflate_buffer fix

[David Lively <dlively@virtualiron.com>]

Oops, forgot:

Signed-off-by: David Lively <dlively@virtualiron.com>

Dave

David Lively wrote:
> Hi -
>   I notice some of my initrds are failing to gunzip:
> ERROR: inflate failed, sts -5
>   These same initrds work fine with Ben Thomas' original
> patch introducing xc_{linux,hvm}_build_mem.  The checked-in
> version changed some declarations from unsigned char * to
> char *, breaking the output length computation in xc_inflate_buffer.
>   This patch assumes you want to keep using the signed char *
> for the interface, so it simply inserts a few casts to unsigned.
> Tested lightly, but the bug is pretty obvious once you notice
> the signedness change ...
> 
> Dave
> 
> 
> ------------------------------------------------------------------------
> 
> diff -r 1d741a415927 tools/libxc/xg_private.c
> --- a/tools/libxc/xg_private.c	Wed Mar 15 11:48:33 2006 -0500
> +++ b/tools/libxc/xg_private.c	Wed Mar 15 12:28:05 2006 -0500
> @@ -77,10 +77,11 @@ char *xc_inflate_buffer(const char *in_b
>          return (char *)in_buf;
>      }
>  
> -    out_len = in_buf[in_size-4] +
> -        (256 * (in_buf[in_size-3] +
> -                (256 * (in_buf[in_size-2] +
> -                        (256 * in_buf[in_size-1])))));
> +    out_len = (unsigned char)in_buf[in_size-4] +
> +        (256 * ((unsigned char)in_buf[in_size-3] +
> +                (256 * ((unsigned char)in_buf[in_size-2] +
> +                        (256 * (unsigned char)in_buf[in_size-1])))));
> +
>      bzero(&zStream, sizeof(zStream));
>      out_buf = malloc(out_len + 16);        /* Leave a little extra space */
>      if ( out_buf == NULL )