Re: sending ioctl warnings for a partition

[Douglas Gilbert <dgilbert@interlog.com>]

On 12-02-04 11:05 AM, Tullio Dovera wrote:
> My platform is based on linux v3.2.2 + Debian stable zfs-fuse-0.6.9-1
> application
>
> When I use a dedicated scsi partition for zfs-fuse I see the following
> warnings at kernel level:
>
> kernel: [   12.881949] zfs-fuse: sending ioctl 2285 to a partition!
>
> The SG_IO is blocked inside scsi_verify_blk_ioctl() function. In order to permit
> SG_IO for a partition I suggest to add it in the white list:
>
> --- a/block/scsi_ioctl.c	2012-02-01 11:10:41.000000000 +0100
> +++ b/block/scsi_ioctl.c	2012-02-01 11:31:09.000000000 +0100
> @@ -710,6 +710,7 @@
>   	case SG_GET_RESERVED_SIZE:
>   	case SG_SET_RESERVED_SIZE:
>   	case SG_EMULATED_HOST:
> +	case SG_IO:
>   		return 0;
>   	case CDROM_GET_CAPABILITY:
>   		/* Keep this until we remove the printk below.  udev sends it

If I'm not mistaken, the whole point of a series of patches
titled: "fail SCSI passthrough ioctls on partition devices"
was to flag and ultimately break any user space code that
attempted to use the SG_IO ioctl on a partition block
device (e.g. send a SCSI INQUIRY via SG_IO to /dev/sda2).

This is for security reasons. So when the kernel enforces
that, zfs-fuse will break. Please alert the zfs-fuse
maintainers.

Doug Gilbert