Merge tag 'scsi-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi

Pull SCSI fixes from James Bottomley:
 "Three fixes, all in drivers. The lpfc one doesn't look exploitable,
  but nasty things could happen in string operations if mybuf ends up
  with an on stack unterminated string"

* tag 'scsi-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi:
  scsi: vmw_pvscsi: Set residual data length conditionally
  scsi: libiscsi: Fix UAF in iscsi_conn_get_param()/iscsi_conn_teardown()
  scsi: lpfc: Terminate string in lpfc_debugfs_nvmeio_trc_write()

3 files changed, 11 insertions, 6 deletions

diff --git a/drivers/scsi/libiscsi.c b/drivers/scsi/libiscsi.c
index 284b939fb1ea..059dae8909ee 100644
--- a/drivers/scsi/libiscsi.c
+++ b/drivers/scsi/libiscsi.c
@@ -3100,6 +3100,8 @@ void iscsi_conn_teardown(struct iscsi_cls_conn *cls_conn)
 {
 	struct iscsi_conn *conn = cls_conn->dd_data;
 	struct iscsi_session *session = conn->session;
+	char *tmp_persistent_address = conn->persistent_address;
+	char *tmp_local_ipaddr = conn->local_ipaddr;
 
 	del_timer_sync(&conn->transport_timer);
 
@@ -3121,8 +3123,6 @@ void iscsi_conn_teardown(struct iscsi_cls_conn *cls_conn)
 	spin_lock_bh(&session->frwd_lock);
 	free_pages((unsigned long) conn->data,
 		   get_order(ISCSI_DEF_MAX_RECV_SEG_LEN));
-	kfree(conn->persistent_address);
-	kfree(conn->local_ipaddr);
 	/* regular RX path uses back_lock */
 	spin_lock_bh(&session->back_lock);
 	kfifo_in(&session->cmdpool.queue, (void*)&conn->login_task,
@@ -3134,6 +3134,8 @@ void iscsi_conn_teardown(struct iscsi_cls_conn *cls_conn)
 	mutex_unlock(&session->eh_mutex);
 
 	iscsi_destroy_conn(cls_conn);
+	kfree(tmp_persistent_address);
+	kfree(tmp_local_ipaddr);
 }
 EXPORT_SYMBOL_GPL(iscsi_conn_teardown);
 
diff --git a/drivers/scsi/lpfc/lpfc_debugfs.c b/drivers/scsi/lpfc/lpfc_debugfs.c
index bd6d459afce5..08b2e85dcd7d 100644
--- a/drivers/scsi/lpfc/lpfc_debugfs.c
+++ b/drivers/scsi/lpfc/lpfc_debugfs.c
@@ -2954,8 +2954,8 @@ lpfc_debugfs_nvmeio_trc_write(struct file *file, const char __user *buf,
 	char mybuf[64];
 	char *pbuf;
 
-	if (nbytes > 64)
-		nbytes = 64;
+	if (nbytes > 63)
+		nbytes = 63;
 
 	memset(mybuf, 0, sizeof(mybuf));
 
diff --git a/drivers/scsi/vmw_pvscsi.c b/drivers/scsi/vmw_pvscsi.c
index c2ba65224633..1f037b8ab904 100644
--- a/drivers/scsi/vmw_pvscsi.c
+++ b/drivers/scsi/vmw_pvscsi.c
@@ -586,9 +586,12 @@ static void pvscsi_complete_request(struct pvscsi_adapter *adapter,
 			 * Commands like INQUIRY may transfer less data than
 			 * requested by the initiator via bufflen. Set residual
 			 * count to make upper layer aware of the actual amount
-			 * of data returned.
+			 * of data returned. There are cases when controller
+			 * returns zero dataLen with non zero data - do not set
+			 * residual count in that case.
 			 */
-			scsi_set_resid(cmd, scsi_bufflen(cmd) - e->dataLen);
+			if (e->dataLen && (e->dataLen < scsi_bufflen(cmd)))
+				scsi_set_resid(cmd, scsi_bufflen(cmd) - e->dataLen);
 			cmd->result = (DID_OK << 16);
 			break;