[PATCH] scsi: ufs: Fix referencing invalid rsp field

[Daejun Park <daejun7.park@samsung.com>]

This is a patch for fixing referencing sense data when it is invalid.
When the length of the data segment is 0, there is no valid information in
the rsp field, so ufshpb_rsp_upiu() is returned without additional
operation.

Signed-off-by: Daejun Park <daejun7.park@samsung.com>
---
 drivers/scsi/ufs/ufshpb.c | 19 +++++++------------
 1 file changed, 7 insertions(+), 12 deletions(-)

diff --git a/drivers/scsi/ufs/ufshpb.c b/drivers/scsi/ufs/ufshpb.c
index f1f65383e97d..8882b47f76d3 100644
--- a/drivers/scsi/ufs/ufshpb.c
+++ b/drivers/scsi/ufs/ufshpb.c
@@ -1304,6 +1304,13 @@ void ufshpb_rsp_upiu(struct ufs_hba *hba, struct ufshcd_lrb *lrbp)
 	struct utp_hpb_rsp *rsp_field = &lrbp->ucd_rsp_ptr->hr;
 	int data_seg_len;
 
+	data_seg_len = be32_to_cpu(lrbp->ucd_rsp_ptr->header.dword_2)
+		& MASK_RSP_UPIU_DATA_SEG_LEN;
+
+	/* If data segment length is zero, rsp_field is not valid */
+	if (!data_seg_len)
+		return;
+
 	if (unlikely(lrbp->lun != rsp_field->lun)) {
 		struct scsi_device *sdev;
 		bool found = false;
@@ -1338,18 +1345,6 @@ void ufshpb_rsp_upiu(struct ufs_hba *hba, struct ufshcd_lrb *lrbp)
 		return;
 	}
 
-	data_seg_len = be32_to_cpu(lrbp->ucd_rsp_ptr->header.dword_2)
-		& MASK_RSP_UPIU_DATA_SEG_LEN;
-
-	/* To flush remained rsp_list, we queue the map_work task */
-	if (!data_seg_len) {
-		if (!ufshpb_is_general_lun(hpb->lun))
-			return;
-
-		ufshpb_kick_map_work(hpb);
-		return;
-	}
-
 	BUILD_BUG_ON(sizeof(struct utp_hpb_rsp) != UTP_HPB_RSP_SIZE);
 
 	if (!ufshpb_is_hpb_rsp_valid(hba, lrbp, rsp_field))
-- 
2.25.1