Re: [PATCH] block: fix bogus EFAULT error from SG_IO ioctl

From: Jeff Moyer
Date: Fri Jun 26 2015 - 10:10:13 EST


Paolo Bonzini <pbonzini@xxxxxxxxxx> writes:

> Whenever blk_fill_sghdr_rq fails, its errno code is ignored and changed to
> EFAULT. This can cause very confusing errors:
>
> $ sg_persist -k /dev/sda
> persistent reservation in: pass through os error: Bad address
>
> The fix is trivial, just propagate the return value from
> blk_fill_sghdr_rq.
>
> Signed-off-by: Paolo Bonzini <pbonzini@xxxxxxxxxx>

Acked-by: Jeff Moyer <jmoyer@xxxxxxxxxx>

> ---
> block/scsi_ioctl.c | 4 ++--
> 1 file changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/block/scsi_ioctl.c b/block/scsi_ioctl.c
> index 55b6f15dac90..dda653ce7b24 100644
> --- a/block/scsi_ioctl.c
> +++ b/block/scsi_ioctl.c
> @@ -326,8 +326,8 @@ static int sg_io(struct request_queue *q, struct gendisk *bd_disk,
> goto out_put_request;
> }
>
> - ret = -EFAULT;
> - if (blk_fill_sghdr_rq(q, rq, hdr, mode))
> + ret = blk_fill_sghdr_rq(q, rq, hdr, mode);
> + if (ret < 0)
> goto out_free_cdb;
>
> ret = 0;
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/