From dca957e7958d47506cb95c60a103f8cb90394413 Mon Sep 17 00:00:00 2001
From: TimothyBanks <tbanks@ripple.com>
Date: Fri, 17 Jul 2026 08:51:25 -0400
Subject: [PATCH] feat: Wasm Module Versioning

---
 src/libxrpl/tx/wasm/WasmiVM.cpp | 30 ++++++++++++++++++++++++++++--
 1 file changed, 28 insertions(+), 2 deletions(-)

diff --git a/src/libxrpl/tx/wasm/WasmiVM.cpp b/src/libxrpl/tx/wasm/WasmiVM.cpp
index 24363e9d06..437c0fe7d7 100644
--- a/src/libxrpl/tx/wasm/WasmiVM.cpp
+++ b/src/libxrpl/tx/wasm/WasmiVM.cpp
@@ -819,7 +819,7 @@ readLEB128(Bytes const& wasmCode, size_t& offset)
 {
     auto result = uint32_t{};
     auto shift = uint32_t{};
-    while (true)
+    while (offset < wasmCode.size())
     {
         auto byte = wasmCode[offset++];
         result |= (byte & 0x7F) << shift;
@@ -828,6 +828,10 @@ readLEB128(Bytes const& wasmCode, size_t& offset)
             break;
         }
         shift += 7;
+        if (shift >= 32)
+        {
+            break;
+        }
     }
     return result;
 }
@@ -838,21 +842,43 @@ filterCustomSections(Bytes const& wasmCode, Filter&& filter)
 {
     auto offset = size_t{8};  // Skip Magic number and Version
 
+    if (wasmCode.size() <= offset)
+    {
+        // There is nothing to parse.
+        return;
+    }
+
     while (offset < wasmCode.size())
     {
         auto sectionId = wasmCode[offset++];
         auto sectionSize = readLEB128(wasmCode, offset);
         auto nextSection = offset + sectionSize;
 
+        if (nextSection >= wasmCode.size())
+        {
+            break;
+        }
+
         if (sectionId == 0)
         {
+            // Wasm custom section marker.
             auto customSection = CustomSection{};
-
             auto size = readLEB128(wasmCode, offset);
+
+            if (offset + size > wasmCode.size() || offset + size > nextSection)
+            {
+                return;
+            }
+
             customSection.name =
                 std::string_view{reinterpret_cast<char const*>(wasmCode.data()) + offset, size};
             offset += size;
 
+            if (offset >= nextSection)
+            {
+                break;
+            }
+
             size = nextSection - offset;
             customSection.payload = std::span<char const>{
                 reinterpret_cast<char const*>(wasmCode.data()) + offset, size};