Merge #14247: Fix crash bug with duplicate inputs within a transaction

9b4a36effc [qa] Test for duplicate inputs within a transaction (Suhas Daftuar)
b8f801964f Fix crash bug with duplicate inputs within a transaction (Suhas Daftuar)

Pull request description:

Tree-SHA512: 8c7ea34c7fa44188d86c04a690a7cbf8e9deda71ab1f7ca6d11de1f2abb3dd7222627071f86d0d39689a8b302ba9af142f0202466a67e30cd54aed3a08d4eb14

src/validation.cpp

@@ -3122,7 +3122,7 @@ bool CheckBlock(const CBlock& block, CValidationState& state, const Consensus::P
 
     // Check transactions
     for (const auto& tx : block.vtx)
-        if (!CheckTransaction(*tx, state, false))
+        if (!CheckTransaction(*tx, state, true))
             return state.Invalid(false, state.GetRejectCode(), state.GetRejectReason(),
                                  strprintf("Transaction check failed (tx hash %s) %s", tx->GetHash().ToString(), state.GetDebugMessage()));
 

test/functional/p2p_invalid_block.py

@@ -81,6 +81,16 @@ class InvalidBlockRequestTest(BitcoinTestFramework):
 
         node.p2p.send_blocks_and_test([block2], node, success=False, request_block=False, reject_reason='bad-txns-duplicate')
 
+        # Check transactions for duplicate inputs
+        self.log.info("Test duplicate input block.")
+
+        block2_orig.vtx[2].vin.append(block2_orig.vtx[2].vin[0])
+        block2_orig.vtx[2].rehash()
+        block2_orig.hashMerkleRoot = block2_orig.calc_merkle_root()
+        block2_orig.rehash()
+        block2_orig.solve()
+        node.p2p.send_blocks_and_test([block2_orig], node, success=False, request_block=False, reject_reason='bad-txns-inputs-duplicate')
+
         self.log.info("Test very broken block.")
 
         block3 = create_block(tip, create_coinbase(height), block_time)