Re: [PATCH] jfs: Fix FITRIM argument handling

[Dave Kleikamp <dave.kleikamp@oracle.com>]

On 10/16/2012 04:38 AM, Lukas Czerner wrote:
> Currently when 'range->start' is beyond the end of file system
> nothing is done and that fact is ignored, where in fact we should return
> EINVAL. The same problem is when 'range.len' is smaller than file system
> block.
> 
> Fix this by adding check for such conditions and return EINVAL
> appropriately.
> 
> Signed-off-by: Lukas Czerner <lczerner@redhat.com>

Looks good. Pushed out to
git://github.com/kleikamp/linux-shaggy.git jfs-next

Should make the next linux-next build.

Thanks,
Shaggy

> ---
>  fs/jfs/jfs_discard.c |   16 ++++++++++------
>  1 files changed, 10 insertions(+), 6 deletions(-)
> 
> diff --git a/fs/jfs/jfs_discard.c b/fs/jfs/jfs_discard.c
> index 9947563..dfcd503 100644
> --- a/fs/jfs/jfs_discard.c
> +++ b/fs/jfs/jfs_discard.c
> @@ -83,7 +83,7 @@ int jfs_ioc_trim(struct inode *ip, struct fstrim_range *range)
>  	struct bmap *bmp = JFS_SBI(ip->i_sb)->bmap;
>  	struct super_block *sb = ipbmap->i_sb;
>  	int agno, agno_end;
> -	s64 start, end, minlen;
> +	u64 start, end, minlen;
>  	u64 trimmed = 0;
>  
>  	/**
> @@ -93,15 +93,19 @@ int jfs_ioc_trim(struct inode *ip, struct fstrim_range *range)
>  	 * minlen:	minimum extent length in Bytes
>  	 */
>  	start = range->start >> sb->s_blocksize_bits;
> -	if (start < 0)
> -		start = 0;
>  	end = start + (range->len >> sb->s_blocksize_bits) - 1;
> -	if (end >= bmp->db_mapsize)
> -		end = bmp->db_mapsize - 1;
>  	minlen = range->minlen >> sb->s_blocksize_bits;
> -	if (minlen <= 0)
> +	if (minlen == 0)
>  		minlen = 1;
>  
> +	if (minlen > bmp->db_agsize ||
> +	    start >= bmp->db_mapsize ||
> +	    range->len < sb->s_blocksize)
> +		return -EINVAL;
> +
> +	if (end >= bmp->db_mapsize)
> +		end = bmp->db_mapsize - 1;
> +
>  	/**
>  	 * we trim all ag's within the range
>  	 */
>