Re: [PATCH 4/5] tcm_vhost: fix iov array offset

["Nicholas A. Bellinger" <nab@xxxxxxxxxxxxxxx>]

On Wed, 2012-04-18 at 15:06 +0800, zwu.kernel@xxxxxxxxx wrote:
> From: Zhi Yong Wu <wuzhy@xxxxxxxxxxxxxxxxxx>
> 
> Signed-off-by: Zhi Yong Wu <wuzhy@xxxxxxxxxxxxxxxxxx>
> ---
>  drivers/target/tcm_vhost/tcm_vhost_scsi.c |   36 +++++++++-------------------
>  1 files changed, 12 insertions(+), 24 deletions(-)
> 
> diff --git a/drivers/target/tcm_vhost/tcm_vhost_scsi.c b/drivers/target/tcm_vhost/tcm_vhost_scsi.c
> index cd8ff54..8b56d59 100644
> --- a/drivers/target/tcm_vhost/tcm_vhost_scsi.c
> +++ b/drivers/target/tcm_vhost/tcm_vhost_scsi.c

<SNIP>

> @@ -353,33 +353,21 @@ static void vhost_scsi_handle_vq(struct vhost_scsi *vs)
>  
>  		tv_cmd->tvc_vhost = vs;
>  
> -		if (unlikely(vq->iov[out + in - 1].iov_len !=
> +		if (unlikely(vq->iov[out].iov_len !=
>  		             sizeof(struct virtio_scsi_cmd_resp))) {
>  			pr_err("Expecting virtio_scsi_cmd_resp, "
> -			       " got %zu bytes\n", vq->iov[out + in - 1].iov_len);
> +			       " got %zu bytes, out: %d, in: %d\n", vq->iov[out].iov_len, out, in);
>  			break;
>  		}
>  
> -		tv_cmd->tvc_resp = vq->iov[out + in -1].iov_base;
> +		tv_cmd->tvc_resp = vq->iov[out].iov_base;
>  
> -		if (unlikely(vq->iov[1].iov_len > TCM_VHOST_MAX_CDB_SIZE)) {
> -			pr_err("CDB length: %zu exceeds %d\n",
> -				vq->iov[1].iov_len, TCM_VHOST_MAX_CDB_SIZE);
> -			/* TODO clean up and free tv_cmd */
> -			break;
> -		}
>  		/*
>  		 * Copy in the recieved CDB descriptor into tv_cmd->tvc_cdb
>  		 * that will be used by tcm_vhost_new_cmd_map() and down into
>  		 * target_setup_cmd_from_cdb()
>  		 */
> -		ret = __copy_from_user(tv_cmd->tvc_cdb, vq->iov[1].iov_base,
> -					vq->iov[1].iov_len);
> -		if (unlikely(ret)) {
> -			pr_err("Faulted on CDB\n");
> -			break; /* TODO should all breaks be continues? */
> -		}
> -
> +                memcpy(tv_cmd->tvc_cdb, v_req.cdb, TCM_VHOST_MAX_CDB_SIZE);
>  		/*
>  		 * Check that the recieved CDB size does not exceeded our
>  		 * hardcoded max for tcm_vhost

Mmm, the section of this patch for vhost_scsi_handle_vq() does not apply
to the current lio-core.git HEAD.

I've applied this section by hand for now.  Also, at little more verbose
changelog would be helpful to other folks reviewing the code.  ;)

--nab





--
To unsubscribe from this list: send the line "unsubscribe target-devel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html