bugfix: calculate L2TPv2 offset

2024-05-30 18:45:39 +08:00
parent 1a7f74025b
commit 2d958dbe07
3 changed files with 32 additions and 29 deletions
--- a/src/packet/packet.cpp
+++ b/src/packet/packet.cpp
@@ -728,7 +728,21 @@ static inline uint16_t get_l2tpv2_hdr_len(const char *data, uint16_t len)
            {
                return 0;
            }
-            return ntohs(*((uint16_t *)(data + skip_len)));
+            uint16_t offset = ntohs(*((uint16_t *)(data + skip_len)));
+            if (offset == 0)
+            {
+                return skip_len + 2;
+            }
+
+            // invalid offset
+            if (offset > len)
+            {
+                return 0;
+            }
+            else
+            {
+                return offset;
+            }
        }
        else
        {