From 1a03839f78b9fffaf038dce3d4b619ea7e053930 Mon Sep 17 00:00:00 2001
From: Andre Puschmann <andre@softwareradiosystems.com>
Date: Fri, 16 Oct 2020 14:20:35 +0200
Subject: [PATCH] rlc_am_lte: fix potential bug when setting uint32_t to -1

discovered in Coverity CID 359664
---
 lib/src/upper/rlc_am_lte.cc | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/lib/src/upper/rlc_am_lte.cc b/lib/src/upper/rlc_am_lte.cc
index 32bbeb64d..1117bd9c8 100644
--- a/lib/src/upper/rlc_am_lte.cc
+++ b/lib/src/upper/rlc_am_lte.cc
@@ -872,7 +872,9 @@ int rlc_am_lte::rlc_am_lte_tx::build_data_pdu(uint8_t* payload, uint32_t nof_byt
     }
     head_len = rlc_am_packed_length(&header);
     if (head_len >= pdu_space) {
-      header.N_li--;
+      if (header.N_li > 0) {
+        header.N_li--;
+      }
       break;
     }
     tx_sdu  = tx_sdu_queue.read();