From a7542604235d4267b1dfdbc2d1f9396289e0381e Mon Sep 17 00:00:00 2001
From: Brannon King <countprimes@gmail.com>
Date: Wed, 11 Sep 2019 15:11:04 -0600
Subject: [PATCH] proposed fix for issue 242

---
 src/nameclaim.cpp          | 1 +
 src/script/interpreter.cpp | 7 +++++--
 2 files changed, 6 insertions(+), 2 deletions(-)

diff --git a/src/nameclaim.cpp b/src/nameclaim.cpp
index ebb223d72..52517697f 100644
--- a/src/nameclaim.cpp
+++ b/src/nameclaim.cpp
@@ -62,6 +62,7 @@ bool DecodeClaimScript(const CScript& scriptIn, int& op, std::vector<std::vector
 
 bool DecodeClaimScript(const CScript& scriptIn, int& op, std::vector<std::vector<unsigned char> >& vvchParams, CScript::const_iterator& pc)
 {
+    op = -1;
     opcodetype opcode;
     if (!scriptIn.GetOp(pc, opcode))
     {
diff --git a/src/script/interpreter.cpp b/src/script/interpreter.cpp
index fa777da78..c86731df5 100644
--- a/src/script/interpreter.cpp
+++ b/src/script/interpreter.cpp
@@ -1493,6 +1493,11 @@ bool VerifyScript(const CScript& scriptSig, const CScript& scriptPubKey, const C
 
     // scriptSig and scriptPubKey must be evaluated sequentially on the same stack
     // rather than being simply concatenated (see CVE-2010-5141)
+    int claimOp;
+    const CScript& strippedScriptPubKey = StripClaimScriptPrefix(scriptPubKey, claimOp);
+    if (claimOp >= 0) // lbryum used to violate this rule with an off-by-1 at len == 255 (and its not very important)
+        flags &= ~SCRIPT_VERIFY_MINIMALDATA;
+
     std::vector<std::vector<unsigned char> > stack, stackCopy;
     if (!EvalScript(stack, scriptSig, flags, checker, SigVersion::BASE, serror))
         // serror is set
@@ -1509,8 +1514,6 @@ bool VerifyScript(const CScript& scriptSig, const CScript& scriptPubKey, const C
 
     // Bare witness programs
 
-    const CScript& strippedScriptPubKey = StripClaimScriptPrefix(scriptPubKey);
-
     int witnessversion;
     std::vector<unsigned char> witnessprogram;
     if (flags & SCRIPT_VERIFY_WITNESS) {