On Fri, 08 May 2015 10:16:23 +1000, NeilBrown <ne...@suse.de> wrote:
> The "fh_len" passed to ->fh_to_* is not guaranteed to be that same as
> that returned by encode_fh - it may be larger.
> 
> With NFSv2, the filehandle is fixed length, so it may appear longer
> than expected and be zero-padded.
> 
> So we must test that fh_len is at least some value, not exactly equal
> to it.
> 
> Signed-off-by: NeilBrown <ne...@suse.de>
> ---
>  fs/nilfs2/namei.c |    6 +++---
>  1 file changed, 3 insertions(+), 3 deletions(-)
> 
> diff --git a/fs/nilfs2/namei.c b/fs/nilfs2/namei.c
> index 22180836ec22..b65fb79d16fd 100644
> --- a/fs/nilfs2/namei.c
> +++ b/fs/nilfs2/namei.c
> @@ -496,8 +496,8 @@ static struct dentry *nilfs_fh_to_dentry(struct 
> super_block *sb, struct fid *fh,
>  {
>       struct nilfs_fid *fid = (struct nilfs_fid *)fh;
>  
> -     if ((fh_len != NILFS_FID_SIZE_NON_CONNECTABLE &&
> -          fh_len != NILFS_FID_SIZE_CONNECTABLE) ||

> +     if ((fh_len < NILFS_FID_SIZE_NON_CONNECTABLE &&
> +          fh_len < NILFS_FID_SIZE_CONNECTABLE) ||
>           (fh_type != FILEID_NILFS_WITH_PARENT &&
>            fh_type != FILEID_NILFS_WITHOUT_PARENT))
>               return NULL;

A bit weird.  "fh_len < NILFS_FID_SIZE_CONNECTABLE" implies "fh_len <
NILFS_FID_SIZE_NON_CONNECTABLE".

How about the following fix ?

        if ((fh_type != FILEID_NILFS_WITH_PARENT ||
             fh_len < NILFS_FID_SIZE_CONNECTABLE) &&
            (fh_type != FILEID_NILFS_WITHOUT_PARENT ||
             fh_len < NILFS_FID_SIZE_NON_CONNECTABLE))
                return NULL;

Regards,
Ryusuke Konishi

> @@ -510,7 +510,7 @@ static struct dentry *nilfs_fh_to_parent(struct 
> super_block *sb, struct fid *fh,
>  {
>       struct nilfs_fid *fid = (struct nilfs_fid *)fh;
>  
> -     if (fh_len != NILFS_FID_SIZE_CONNECTABLE ||
> +     if (fh_len < NILFS_FID_SIZE_CONNECTABLE ||
>           fh_type != FILEID_NILFS_WITH_PARENT)
>               return NULL;
>  
> 
> 
> --
> To unsubscribe from this list: send the line "unsubscribe linux-nilfs" in
> the body of a message to majord...@vger.kernel.org
> More majordomo info at  http://vger.kernel.org/majordomo-info.html
--
To unsubscribe from this list: send the line "unsubscribe linux-nilfs" in
the body of a message to majord...@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html

Reply via email to