Re: [PATCH 06/22] FIX: Initialize reshape structure

[NeilBrown <neilb@suse.de>]

On Thu, 02 Jun 2011 16:49:00 +0200 Krzysztof Wojcik
<krzysztof.wojcik@intel.com> wrote:

> From: Adam Kwolek <adam.kwolek@intel.com>
> 
> It can occurs that reshape structure can contain random values.
> Due to this fact analyse_change() can disallow for grow start
> without real cause (e.g. check of uninitialized new_chunk).
> 
> Signed-off-by: Adam Kwolek <adam.kwolek@intel.com>
> ---
>  Grow.c |    1 +
>  1 files changed, 1 insertions(+), 0 deletions(-)
> 
> diff --git a/Grow.c b/Grow.c
> index 7a8ffdb..11b2214 100644
> --- a/Grow.c
> +++ b/Grow.c
> @@ -1745,6 +1745,7 @@ static int reshape_array(char *container, int fd, char *devname,
>  		info->component_size = array_size / array.raid_disks;
>  	}
>  
> +	memset(&reshape, 0, sizeof(reshape));
>  	if (info->reshape_active) {
>  		int new_level = info->new_level;
>  		info->new_level = UnSet;


This doesn't make any sense to me.

I cannot see how any random numbers in 'reshape' can cause analyse_change to
do the wrong thing, and there is no "new_chunk" in 'reshape' that could be
"uninitialized"..

Please explain.

NeilBrown