[PATCH v2 4/6] bsg: allow cmd_len > 32

[Douglas Gilbert <dgilbert@interlog.com>]

Since the bsg interface accesses the CDB via scsi_cmnd::cmnd
directly, change that to use the new access functions.

Signed-off-by: Douglas Gilbert <dgilbert@interlog.com>
---
 drivers/scsi/scsi_bsg.c | 22 +++++++++++++++-------
 1 file changed, 15 insertions(+), 7 deletions(-)

diff --git a/drivers/scsi/scsi_bsg.c b/drivers/scsi/scsi_bsg.c
index 96ee35256a16..0001a95c6ce1 100644
--- a/drivers/scsi/scsi_bsg.c
+++ b/drivers/scsi/scsi_bsg.c
@@ -15,6 +15,7 @@ static int scsi_bsg_sg_io_fn(struct request_queue *q, struct sg_io_v4 *hdr,
 	struct scsi_cmnd *scmd;
 	struct request *rq;
 	struct bio *bio;
+	u8 *cdb;
 	int ret;
 
 	if (hdr->protocol != BSG_PROTOCOL_SCSI  ||
@@ -33,17 +34,24 @@ static int scsi_bsg_sg_io_fn(struct request_queue *q, struct sg_io_v4 *hdr,
 
 	scmd = blk_mq_rq_to_pdu(rq);
 	scmd->cmd_len = hdr->request_len;
-	if (scmd->cmd_len > sizeof(scmd->cmnd)) {
+	if (unlikely(scmd->cmd_len > SCSI_MAX_RUN_TIME_CDB_LEN)) {
 		ret = -EINVAL;
 		goto out_put_request;
 	}
+	cdb = scsi_cmnd_set_cdb(scmd, NULL, scmd->cmd_len);
+	if (unlikely(!cdb)) {
+		ret = -ENOMEM;
+		goto out_put_request;
+	}
 
-	ret = -EFAULT;
-	if (copy_from_user(scmd->cmnd, uptr64(hdr->request), scmd->cmd_len))
+	if (unlikely(copy_from_user(cdb, uptr64(hdr->request), scmd->cmd_len))) {
+		ret = -EFAULT;
 		goto out_put_request;
-	ret = -EPERM;
-	if (!scsi_cmd_allowed(scmd->cmnd, mode))
+	}
+	if (unlikely(!scsi_cmd_allowed(cdb, mode))) {
+		ret = -EPERM;
 		goto out_put_request;
+	}
 
 	ret = 0;
 	if (hdr->dout_xfer_len) {
@@ -54,7 +62,7 @@ static int scsi_bsg_sg_io_fn(struct request_queue *q, struct sg_io_v4 *hdr,
 				hdr->din_xfer_len, GFP_KERNEL);
 	}
 
-	if (ret)
+	if (unlikely(ret))
 		goto out_put_request;
 
 	bio = rq->bio;
@@ -92,7 +100,7 @@ static int scsi_bsg_sg_io_fn(struct request_queue *q, struct sg_io_v4 *hdr,
 	blk_rq_unmap_user(bio);
 
 out_put_request:
-	blk_mq_free_request(rq);
+	scsi_free_cmnd(scmd);
 	return ret;
 }
 
-- 
2.25.1