scsi: sg: fix static checker warning in sg_is_valid_dxfer

dxfer_len is an unsigned int and we always assign a value > 0 to it, so
it doesn't make any sense to check if it is < 0. We can't really check
dxferp as well as we have both NULL and not NULL cases in the possible
call paths.

So just return true for SG_DXFER_FROM_DEV transfer in
sg_is_valid_dxfer().

Signed-off-by: Johannes Thumshirn <jthumshirn@suse.de>
Reported-by: Colin Ian King <colin.king@canonical.com>
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Cc: Douglas Gilbert <dgilbert@interlog.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
This commit is contained in:
Johannes Thumshirn 2017-07-17 15:11:42 +02:00 committed by Martin K. Petersen
parent eeee410754
commit 14074aba4b

View File

@ -759,8 +759,11 @@ static bool sg_is_valid_dxfer(sg_io_hdr_t *hp)
return false;
return true;
case SG_DXFER_FROM_DEV:
if (hp->dxfer_len < 0)
return false;
/*
* for SG_DXFER_FROM_DEV we always set dxfer_len to > 0. dxferp
* can either be NULL or != NULL so there's no point in checking
* it either. So just return true.
*/
return true;
case SG_DXFER_TO_DEV:
case SG_DXFER_TO_FROM_DEV: