[RESENT PATCH v5 3/5] scsi: ufs: fix potential access NULL pointer while memcpy

[Bean Huo]

From: Bean Huo <beanhuo@xxxxxxxxxx>

If param_offset is not 0, the memcpy length shouldn't be the
true descriptor length.

Signed-off-by: Bean Huo <beanhuo@xxxxxxxxxx>
---
 drivers/scsi/ufs/ufshcd.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/scsi/ufs/ufshcd.c b/drivers/scsi/ufs/ufshcd.c
index c18c2aadbe14..7163b268ed0b 100644
--- a/drivers/scsi/ufs/ufshcd.c
+++ b/drivers/scsi/ufs/ufshcd.c
@@ -3210,8 +3210,8 @@ int ufshcd_read_desc_param(struct ufs_hba *hba,
 	}
 
 	/* Check wherher we will not copy more data, than available */
-	if (is_kmalloc && param_size > buff_len)
-		param_size = buff_len;
+	if (is_kmalloc && (param_offset + param_size) > buff_len)
+		param_size = buff_len - param_offset;
 
 	if (is_kmalloc)
 		memcpy(param_read_buf, &desc_buf[param_offset], param_size);
-- 
2.17.1