[PATCH 4.9 022/102] scsi: ufs: Check that space was properly alloced in copy_query_response

[Greg Kroah-Hartman]

[ Upstream commit 1c90836f70f9a8ef7b7ad9e1fdd8961903e6ced6 ]

struct ufs_dev_cmd is the main container that supports device management
commands. In the case of a read descriptor request, we assume that the
proper space was allocated in dev_cmd to hold the returning descriptor.

This is no longer true, as there are flows that doesn't use dev_cmd for
device management requests, and was wrong in the first place.

Fixes: d44a5f98bb49 (ufs: query descriptor API)
Signed-off-by: Avri Altman <avri.altman@xxxxxxx>
Reviewed-by: Alim Akhtar <alim.akhtar@xxxxxxxxxxx>
Acked-by: Bean Huo <beanhuo@xxxxxxxxxx>
Signed-off-by: Martin K. Petersen <martin.petersen@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
 drivers/scsi/ufs/ufshcd.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/scsi/ufs/ufshcd.c b/drivers/scsi/ufs/ufshcd.c
index 0fe4f8e8c8c9..a9c172692f21 100644
--- a/drivers/scsi/ufs/ufshcd.c
+++ b/drivers/scsi/ufs/ufshcd.c
@@ -941,7 +941,8 @@ int ufshcd_copy_query_response(struct ufs_hba *hba, struct ufshcd_lrb *lrbp)
 	memcpy(&query_res->upiu_res, &lrbp->ucd_rsp_ptr->qr, QUERY_OSF_SIZE);
 
 	/* Get the descriptor */
-	if (lrbp->ucd_rsp_ptr->qr.opcode == UPIU_QUERY_OPCODE_READ_DESC) {
+	if (hba->dev_cmd.query.descriptor &&
+	    lrbp->ucd_rsp_ptr->qr.opcode == UPIU_QUERY_OPCODE_READ_DESC) {
 		u8 *descp = (u8 *)lrbp->ucd_rsp_ptr +
 				GENERAL_UPIU_REQUEST_SIZE;
 		u16 resp_len;
-- 
2.20.1