diff --git a/src/common/Patch.cpp b/src/common/Patch.cpp
index d908e89b..07daabfb 100644
--- a/src/common/Patch.cpp
+++ b/src/common/Patch.cpp
@@ -232,16 +232,25 @@ static bool patchApplyUPS(const char *patchname, u8 **rom, int *size)
   s64 dstSize = readVarPtr(f);
 
   if (crc == srcCRC) {
-    dataSize = srcSize;
-  } else if (crc == dstCRC) {
+    if (srcSize != *size) {
+      fclose(f);
+      return false;
+    }
     dataSize = dstSize;
+  } else if (crc == dstCRC) {
+    if (dstSize != *size) {
+      fclose(f);
+      return false;
+    }
+    dataSize = srcSize;
   } else {
     fclose(f);
     return false;
   }
-  if (dataSize != *size) {
-    fclose(f);
-    return false;
+  if (dataSize > *size) {
+    *rom = (u8*)realloc(*rom, dataSize);
+    memset(*rom + *size, 0, dataSize - *size);
+    *size = dataSize;
   }
 
   s64 relative = 0;