Re: [PATCH Bakeathon 1/2] NFSv4.1: allow zero fh array in filelayout decode layout

[Benny Halevy <bhalevy.lists@gmail.com>]

On 2011-06-13 16:11, andros@netapp.com wrote:
> From: Andy Adamson <andros@netapp.com>
> 
> Signed-off-by: Andy Adamson <andros@netapp.com>
> cc:stable@kernel.org [2.6.39]
> ---
>  fs/nfs/nfs4filelayout.c |   13 ++++++++-----
>  1 files changed, 8 insertions(+), 5 deletions(-)
> 
> diff --git a/fs/nfs/nfs4filelayout.c b/fs/nfs/nfs4filelayout.c
> index 2cfeaeb..3a8bd92 100644
> --- a/fs/nfs/nfs4filelayout.c
> +++ b/fs/nfs/nfs4filelayout.c
> @@ -551,13 +551,16 @@ filelayout_decode_layout(struct pnfs_layout_hdr *flo,
>  		__func__, nfl_util, fl->num_fh, fl->first_stripe_index,
>  		fl->pattern_offset);
>  
> -	if (!fl->num_fh)
> +	if (fl->num_fh < 0 || fl->num_fh >

num_fh is unsigned so checking for < 0 is not really needed.

Benny

> +	    max(NFS4_PNFS_MAX_STRIPE_CNT, NFS4_PNFS_MAX_MULTI_CNT))
>  		goto out_err;
>  
> -	fl->fh_array = kzalloc(fl->num_fh * sizeof(struct nfs_fh *),
> -			       gfp_flags);
> -	if (!fl->fh_array)
> -		goto out_err;
> +	if (fl->num_fh > 0) {
> +		fl->fh_array = kzalloc(fl->num_fh * sizeof(struct nfs_fh *),
> +				       gfp_flags);
> +		if (!fl->fh_array)
> +			goto out_err;
> +	}
>  
>  	for (i = 0; i < fl->num_fh; i++) {
>  		/* Do we want to use a mempool here? */