From e495c90ee41009ab9c6a5c42425c4cf599188e19 Mon Sep 17 00:00:00 2001
From: 5mil <5mil@users.noreply.github.com>
Date: Fri, 11 Mar 2016 09:41:35 -0500
Subject: [PATCH] Code fix

fix for these issues https://lists.linuxfoundation.org/pipermail/bitcoin-dev/2015-July/009697.html
---
 src/key.cpp | 23 ++++++++++++++++++++++-
 1 file changed, 22 insertions(+), 1 deletion(-)

diff --git a/src/key.cpp b/src/key.cpp
index e40cd53f457..adf67ad0a04 100644
--- a/src/key.cpp
+++ b/src/key.cpp
@@ -354,8 +354,29 @@ bool CKey::SetCompactSignature(uint256 hash, const std::vector<unsigned char>& v
     return false;
 }
 
-bool CKey::Verify(uint256 hash, const std::vector<unsigned char>& vchSig)
+bool CKey::Verify(uint256 hash, const std::vector<unsigned char>& vchSigParam)
 {
+    // Prevent the problem described here: https://lists.linuxfoundation.org/pipermail/bitcoin-dev/2015-July/009697.html
+    // by removing the extra length bytes
+    std::vector<unsigned char> vchSig(vchSigParam.begin(), vchSigParam.end());
+    if (vchSig.size() > 1 && vchSig[1] & 0x80)
+    {
+        unsigned char nLengthBytes = vchSig[1] & 0x7f;
+
+        if (vchSig.size() < 2 + nLengthBytes)
+            return false;
+
+        if (nLengthBytes > 4)
+        {
+            unsigned char nExtraBytes = nLengthBytes - 4;
+            for (unsigned char i = 0; i < nExtraBytes; i++)
+                if (vchSig[2 + i])
+                    return false;
+            vchSig.erase(vchSig.begin() + 2, vchSig.begin() + 2 + nExtraBytes);
+            vchSig[1] = 0x80 | (nLengthBytes - nExtraBytes);
+        }
+    }
+
     if (vchSig.empty())
         return false;