diff --git a/drivers/scsi/hpsa.c b/drivers/scsi/hpsa.c
index 5828bcb82964..959eeb202d92 100644
--- a/drivers/scsi/hpsa.c
+++ b/drivers/scsi/hpsa.c
@@ -2310,6 +2310,7 @@ static int hpsa_ioctl32_passthru(struct scsi_device *dev, int cmd, void *arg)
 	int err;
 	u32 cp;
 
+	memset(&arg64, 0, sizeof(arg64));
 	err = 0;
 	err |= copy_from_user(&arg64.LUN_info, &arg32->LUN_info,
 			   sizeof(arg64.LUN_info));
@@ -2346,6 +2347,7 @@ static int hpsa_ioctl32_big_passthru(struct scsi_device *dev,
 	int err;
 	u32 cp;
 
+	memset(&arg64, 0, sizeof(arg64));
 	err = 0;
 	err |= copy_from_user(&arg64.LUN_info, &arg32->LUN_info,
 			   sizeof(arg64.LUN_info));