[ovs-dev] [Simple DB Stats 06/11] ovsdb-idlc: Fix sizeof calculation in generated code.

[Justin Pettit]

Nice catch!

--Justin


On Jun 10, 2010, at 5:14 PM, Ben Pfaff wrote:

> Generated <prefix>_<struct>_parse_<column> functions did not allocate
> enough memory for the "value" array, because code that should have said,
> e.g.:
>    row->value_options = xmalloc(datum->n * sizeof *row->value_options);
> actually said:
>    row->value_options = xmalloc(datum->n * sizeof row->value_options);
> 
> This fixes the problem.  I also checked that the same problem didn't occur
> elsewhere in the generated code.
> 
> (This would be a fairly serious bug fix, because without it reads and
> writes beyond the end of allocated memory would be almost inevitable,
> except that every existing map has string values, and sizeof(char*)
> == sizeof(char**) on any sane system.)
> ---
> ovsdb/ovsdb-idlc.in |    2 +-
> 1 files changed, 1 insertions(+), 1 deletions(-)
> 
> diff --git a/ovsdb/ovsdb-idlc.in b/ovsdb/ovsdb-idlc.in
> index c89048e..d545d64 100755
> --- a/ovsdb/ovsdb-idlc.in
> +++ b/ovsdb/ovsdb-idlc.in
> @@ -311,7 +311,7 @@ static void
>                 print "%sif (!row->n_%s) {" % (indent, columnName)
>                 print "%s    %s = xmalloc(%s * sizeof *%s);" % (indent, keyVar, nMax, keyVar)
>                 if valueVar:
> -                    print "%s    %s = xmalloc(%s * sizeof %s);" % (indent, valueVar, nMax, valueVar)
> +                    print "%s    %s = xmalloc(%s * sizeof *%s);" % (indent, valueVar, nMax, valueVar)
>                 print "%s}" % indent
>                 print "%s%s[row->n_%s] = %s;" % (indent, keyVar, columnName, keySrc)
>                 if valueVar:
> -- 
> 1.7.1
> 
> 
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