Added comments referencing multiple CVEs in tests and production code.

This commit adds comments referencing multiple CVEs both in production and test code.
CVEs covered in this commit:

CVE-2010-5137
CVE-2010-5139
CVE-2010-5141
CVE-2012-1909
CVE-2012-2459
CVE-2012-3789
CVE-2018-17144

Author: lucash-dev

src/consensus/tx_check.cpp

@@ -18,7 +18,7 @@ bool CheckTransaction(const CTransaction& tx, CValidationState &state, bool fChe
     if (::GetSerializeSize(tx, PROTOCOL_VERSION | SERIALIZE_TRANSACTION_NO_WITNESS) * WITNESS_SCALE_FACTOR > MAX_BLOCK_WEIGHT)
         return state.Invalid(ValidationInvalidReason::CONSENSUS, false, REJECT_INVALID, "bad-txns-oversize");
 
-    // Check for negative or overflow output values
+    // Check for negative or overflow output values (see CVE-2010-5139)
     CAmount nValueOut = 0;
     for (const auto& txout : tx.vout)
     {

src/net_processing.cpp

@@ -2513,7 +2513,7 @@ bool static ProcessMessage(CNode* pfrom, const std::string& strCommand, CDataStr
                 }
                 AddOrphanTx(ptx, pfrom->GetId());
 
-                // DoS prevention: do not allow mapOrphanTransactions to grow unbounded
+                // DoS prevention: do not allow mapOrphanTransactions to grow unbounded (see CVE-2012-3789)
                 unsigned int nMaxOrphanTx = (unsigned int)std::max((int64_t)0, gArgs.GetArg("-maxorphantx", DEFAULT_MAX_ORPHAN_TRANSACTIONS));
                 unsigned int nEvicted = LimitOrphanTxSize(nMaxOrphanTx);
                 if (nEvicted > 0) {

src/script/interpreter.cpp

@@ -334,7 +334,7 @@ bool EvalScript(std::vector<std::vector<unsigned char> >& stack, const CScript&
                 opcode == OP_MOD ||
                 opcode == OP_LSHIFT ||
                 opcode == OP_RSHIFT)
-                return set_error(serror, SCRIPT_ERR_DISABLED_OPCODE); // Disabled opcodes.
+                return set_error(serror, SCRIPT_ERR_DISABLED_OPCODE); // Disabled opcodes (CVE-2010-5137).
 
             // With SCRIPT_VERIFY_CONST_SCRIPTCODE, OP_CODESEPARATOR in non-segwit script is rejected even in an unexecuted branch
             if (opcode == OP_CODESEPARATOR && sigversion == SigVersion::BASE && (flags & SCRIPT_VERIFY_CONST_SCRIPTCODE))
@@ -1483,6 +1483,8 @@ bool VerifyScript(const CScript& scriptSig, const CScript& scriptPubKey, const C
         return set_error(serror, SCRIPT_ERR_SIG_PUSHONLY);
     }
 
+    // scriptSig and scriptPubKey must be evaluated sequentially on the same stack
+    // rather than being simply concatenated (see CVE-2010-5141)
     std::vector<std::vector<unsigned char> > stack, stackCopy;
     if (!EvalScript(stack, scriptSig, flags, checker, SigVersion::BASE, serror))
         // serror is set

src/test/data/script_tests.json

@@ -829,15 +829,16 @@
 ["NOP", "2SWAP 1", "P2SH,STRICTENC", "INVALID_STACK_OPERATION"],
 ["1", "2 3 2SWAP 1", "P2SH,STRICTENC", "INVALID_STACK_OPERATION"],
 
+
+["NOP", "SIZE 1", "P2SH,STRICTENC", "INVALID_STACK_OPERATION"],
+
+["TEST DISABLED OP CODES (CVE-2010-5137)"],
 ["'a' 'b'", "CAT", "P2SH,STRICTENC", "DISABLED_OPCODE", "CAT disabled"],
 ["'a' 'b' 0", "IF CAT ELSE 1 ENDIF", "P2SH,STRICTENC", "DISABLED_OPCODE", "CAT disabled"],
 ["'abc' 1 1", "SUBSTR", "P2SH,STRICTENC", "DISABLED_OPCODE", "SUBSTR disabled"],
 ["'abc' 1 1 0", "IF SUBSTR ELSE 1 ENDIF", "P2SH,STRICTENC", "DISABLED_OPCODE", "SUBSTR disabled"],
 ["'abc' 2 0", "IF LEFT ELSE 1 ENDIF", "P2SH,STRICTENC", "DISABLED_OPCODE", "LEFT disabled"],
 ["'abc' 2 0", "IF RIGHT ELSE 1 ENDIF", "P2SH,STRICTENC", "DISABLED_OPCODE", "RIGHT disabled"],
-
-["NOP", "SIZE 1", "P2SH,STRICTENC", "INVALID_STACK_OPERATION"],
-
 ["'abc'", "IF INVERT ELSE 1 ENDIF", "P2SH,STRICTENC", "DISABLED_OPCODE", "INVERT disabled"],
 ["1 2 0 IF AND ELSE 1 ENDIF", "NOP", "P2SH,STRICTENC", "DISABLED_OPCODE", "AND disabled"],
 ["1 2 0 IF OR ELSE 1 ENDIF", "NOP", "P2SH,STRICTENC", "DISABLED_OPCODE", "OR disabled"],

src/validation.cpp

@@ -1865,7 +1865,7 @@ bool CChainState::ConnectBlock(const CBlock& block, CValidationState& state, CBl
     // If such overwrites are allowed, coinbases and transactions depending upon those
     // can be duplicated to remove the ability to spend the first instance -- even after
     // being sent to another address.
-    // See BIP30 and http://r6.ca/blog/20120206T005236Z.html for more information.
+    // See BIP30, CVE-2012-1909, and http://r6.ca/blog/20120206T005236Z.html for more information.
     // This logic is not necessary for memory pool transactions, as AcceptToMemoryPool
     // already refuses previously-known transaction ids entirely.
     // This rule was originally applied to all blocks with a timestamp after March 15, 2012, 0:00 UTC.
@@ -3136,6 +3136,7 @@ bool CheckBlock(const CBlock& block, CValidationState& state, const Consensus::P
             return state.Invalid(ValidationInvalidReason::CONSENSUS, false, REJECT_INVALID, "bad-cb-multiple", "more than one coinbase");
 
     // Check transactions
+    // Must check for duplicate inputs (see CVE-2018-17144)
     for (const auto& tx : block.vtx)
         if (!CheckTransaction(*tx, state, true))
             return state.Invalid(state.GetReason(), false, state.GetRejectCode(), state.GetRejectReason(),

test/functional/feature_block.py

@@ -787,7 +787,7 @@ def run_test(self):
         #
         # Blocks are not allowed to contain a transaction whose id matches that of an earlier,
         # not-fully-spent transaction in the same chain. To test, make identical coinbases;
-        # the second one should be rejected.
+        # the second one should be rejected. See also CVE-2012-1909.
         #
         self.log.info("Reject a block with a transaction with a duplicate hash of a previous transaction (BIP30)")
         self.move_tip(60)

test/functional/mempool_accept.py

@@ -212,6 +212,7 @@ def run_test(self):
             rawtxs=[tx.serialize().hex()],
         )
 
+        # The following two validations prevent overflow of the output amounts (see CVE-2010-5139).
         self.log.info('A transaction with too large output value')
         tx.deserialize(BytesIO(hex_str_to_bytes(raw_tx_reference)))
         tx.vout[0].nValue = 21000000 * COIN + 1

test/functional/p2p_invalid_block.py

@@ -53,10 +53,11 @@ def run_test(self):
         block_time = best_block["time"] + 1
 
         # Use merkle-root malleability to generate an invalid block with
-        # same blockheader.
+        # same blockheader (CVE-2012-2459).
         # Manufacture a block with 3 transactions (coinbase, spend of prior
         # coinbase, spend of that spend).  Duplicate the 3rd transaction to
         # leave merkle root and blockheader unchanged but invalidate the block.
+        # For more information on merkle-root malleability see src/consensus/merkle.cpp.
         self.log.info("Test merkle root malleability.")
 
         block2 = create_block(tip, create_coinbase(height), block_time)
@@ -81,7 +82,7 @@ def run_test(self):
 
         node.p2p.send_blocks_and_test([block2], node, success=False, reject_reason='bad-txns-duplicate')
 
-        # Check transactions for duplicate inputs
+        # Check transactions for duplicate inputs (CVE-2018-17144)
         self.log.info("Test duplicate input block.")
 
         block2_orig.vtx[2].vin.append(block2_orig.vtx[2].vin[0])