diff --git a/drivers/usb/host/xhci-ring.c b/drivers/usb/host/xhci-ring.c
index 97cf8e1fc07c..9828c1eff9a5 100644
--- a/drivers/usb/host/xhci-ring.c
+++ b/drivers/usb/host/xhci-ring.c
@@ -3403,8 +3403,8 @@ int xhci_queue_bulk_tx(struct xhci_hcd *xhci, gfp_t mem_flags,
 			/* New sg entry */
 			--num_sgs;
 			sent_len -= block_len;
-			if (num_sgs != 0) {
-				sg = sg_next(sg);
+			sg = sg_next(sg);
+			if (num_sgs != 0 && sg) {
 				block_len = sg_dma_len(sg);
 				addr = (u64) sg_dma_address(sg);
 				addr += sent_len;