diff --git a/drivers/input/misc/ims-pcu.c b/drivers/input/misc/ims-pcu.c
index f69de9762c4e..4c022a36dbe8 100644
--- a/drivers/input/misc/ims-pcu.c
+++ b/drivers/input/misc/ims-pcu.c
@@ -438,6 +438,14 @@ static void ims_pcu_handle_response(struct ims_pcu *pcu)
 	}
 }
 
+static void ims_pcu_reset_packet(struct ims_pcu *pcu)
+{
+	pcu->have_stx = true;
+	pcu->have_dle = false;
+	pcu->read_pos = 0;
+	pcu->check_sum = 0;
+}
+
 static void ims_pcu_process_data(struct ims_pcu *pcu, struct urb *urb)
 {
 	int i;
@@ -450,6 +458,14 @@ static void ims_pcu_process_data(struct ims_pcu *pcu, struct urb *urb)
 			continue;
 
 		if (pcu->have_dle) {
+			if (pcu->read_pos >= IMS_PCU_BUF_SIZE) {
+				dev_warn(pcu->dev,
+					 "Packet too long (%d bytes), discarding\n",
+					 pcu->read_pos);
+				ims_pcu_reset_packet(pcu);
+				continue;
+			}
+
 			pcu->have_dle = false;
 			pcu->read_buf[pcu->read_pos++] = data;
 			pcu->check_sum += data;
@@ -462,10 +478,8 @@ static void ims_pcu_process_data(struct ims_pcu *pcu, struct urb *urb)
 				dev_warn(pcu->dev,
 					 "Unexpected STX at byte %d, discarding old data\n",
 					 pcu->read_pos);
+			ims_pcu_reset_packet(pcu);
 			pcu->have_stx = true;
-			pcu->have_dle = false;
-			pcu->read_pos = 0;
-			pcu->check_sum = 0;
 			break;
 
 		case IMS_PCU_PROTOCOL_DLE:
@@ -485,12 +499,18 @@ static void ims_pcu_process_data(struct ims_pcu *pcu, struct urb *urb)
 				ims_pcu_handle_response(pcu);
 			}
 
-			pcu->have_stx = false;
-			pcu->have_dle = false;
-			pcu->read_pos = 0;
+			ims_pcu_reset_packet(pcu);
 			break;
 
 		default:
+			if (pcu->read_pos >= IMS_PCU_BUF_SIZE) {
+				dev_warn(pcu->dev,
+					 "Packet too long (%d bytes), discarding\n",
+					 pcu->read_pos);
+				ims_pcu_reset_packet(pcu);
+				continue;
+			}
+
 			pcu->read_buf[pcu->read_pos++] = data;
 			pcu->check_sum += data;
 			break;