M17: FrameDecoder: decodeLich: added validation of LICH chunk number

2024-12-23 12:40:57 +01:00 · 2024-12-23 12:40:57 +01:00 · 4f791a8f09
parent 7993074a6a
commit 4f791a8f09
1 changed files with 5 additions and 1 deletions
--- a/openrtx/src/protocols/M17/M17FrameDecoder.cpp
+++ b/openrtx/src/protocols/M17/M17FrameDecoder.cpp
@ -202,8 +202,12 @@ bool M17FrameDecoder::decodeLich(std::array < uint8_t, 6 >& segment,
    }

    // Last byte of the segment contains the segment number, shift left
-    // by five when packing the LICH.
+    // by five when packing the LICH. The segment number must range between
+    // zero and five.
    segment[5] >>= 5;

+    if(segment[5] > 5)
+        return false;
+
    return true;
 }