scsi: sg: fix SG_DXFER_FROM_DEV transfers

SG_DXFER_FROM_DEV transfers do not necessarily have a dxferp as we set
it to NULL for the old sg_io read/write interface, but must have a
length bigger than 0. This fixes a regression introduced by commit
28676d869b ("scsi: sg: check for valid direction before starting the
request")

Signed-off-by: Johannes Thumshirn <jthumshirn@suse.de>
Fixes: 28676d869b ("scsi: sg: check for valid direction before starting the request")
Reported-by: Chris Clayton <chris2553@googlemail.com>
Tested-by: Chris Clayton <chris2553@googlemail.com>
Cc: Douglas Gilbert <dgilbert@interlog.com>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Tested-by: Chris Clayton <chris2553@googlemail.com>
Acked-by: Douglas Gilbert <dgilbert@interlog.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
This commit is contained in:
Johannes Thumshirn 2017-07-07 10:56:38 +02:00 committed by Martin K. Petersen
parent a680f1d463
commit 68c59fcea1

View File

@ -758,8 +758,11 @@ static bool sg_is_valid_dxfer(sg_io_hdr_t *hp)
if (hp->dxferp || hp->dxfer_len > 0)
return false;
return true;
case SG_DXFER_TO_DEV:
case SG_DXFER_FROM_DEV:
if (hp->dxfer_len < 0)
return false;
return true;
case SG_DXFER_TO_DEV:
case SG_DXFER_TO_FROM_DEV:
if (!hp->dxferp || hp->dxfer_len == 0)
return false;