Add guards around memcmp and memset to fix ubsan runtime errors. (#74282

) Co-authored-by: Jan Kotas <[email protected]>
dotnet · Aug 20, 2022 · 5958eeb · 5958eeb
1 parent 1d94433
commit 5958eeb
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Showing 2 changed files with 5 additions and 3 deletions.
diff --git a/src/coreclr/inc/sbuffer.inl b/src/coreclr/inc/sbuffer.inl
@@ -258,7 +258,8 @@ inline void SBuffer::Set(const BYTE *buffer, COUNT_T size)
     // From the code for Resize, this is clearly impossible.
     PREFIX_ASSUME( (this->m_buffer != NULL) || (size == 0) );
 
-    MoveMemory(m_buffer, buffer, size);
+    if (size != 0)
+        MoveMemory(m_buffer, buffer, size);
 
     RETURN;
 }

diff --git a/src/coreclr/vm/baseassemblyspec.inl b/src/coreclr/vm/baseassemblyspec.inl
@@ -243,10 +243,11 @@ inline BOOL BaseAssemblySpec::CompareEx(BaseAssemblySpec *pSpec, DWORD dwCompare
             || strcmp(m_pAssemblyName, pSpec->m_pAssemblyName)))
         return FALSE;
 
-    if (m_cbPublicKeyOrToken != pSpec->m_cbPublicKeyOrToken
-        || memcmp(m_pbPublicKeyOrToken, pSpec->m_pbPublicKeyOrToken, m_cbPublicKeyOrToken))
+    if (m_cbPublicKeyOrToken != pSpec->m_cbPublicKeyOrToken)
         return FALSE;
 
+    if (m_cbPublicKeyOrToken != 0 && memcmp(m_pbPublicKeyOrToken, pSpec->m_pbPublicKeyOrToken, m_cbPublicKeyOrToken) != 0)
+        return FALSE;
 
     if (m_dwFlags != pSpec->m_dwFlags)
         return FALSE;