Touch up signer check example

Author: smoelius

not-so-smart-contracts/solana/signer_check/README.md

@@ -4,19 +4,19 @@ In Solana, each public key has an associated private key that can be used to gen
 In case certain permissions are required to perform a sensitive function of the contract, a missing signer check becomes an issue. Without this check, an attacker would be able to call the respective access controlled functions permissionlessly.
 
 ## Exploit Scenario
-The following contract sets an escrow account's state to `Complete`. Unfortunately, the contract does not check whether the escrow account holder has signed the transaction.
-Therefore, a malicious actor can set the state to `Complete`, without needing access to the escrow account holders’s private key.
+The following contract sets an escrow account's state to `Complete`. Unfortunately, the contract does not check whether the `State` account's `authority` has signed the transaction.
+Therefore, a malicious actor can set the state to `Complete`, without needing access to the `authority`’s private key.
 
 ### Example Contract
 ```rust
-fn pay_escrow(_program_id: &Pubkey, accounts: &[AccountInfo], _instruction_data: &[u8]) -> ProgramResult {
+fn complete_escrow(_program_id: &Pubkey, accounts: &[AccountInfo], _instruction_data: &[u8]) -> ProgramResult {
     let account_info_iter = &mut accounts.iter();
     let state_info = next_account_info(account_info_iter)?;
     let authority = next_account_info(account_info_iter)?;
 
     let mut state = State::deserialize(&mut &**state_info.data.borrow())?;
 
-    if state.authority == authority.key {
+    if &state.authority == authority.key {
         state.escrow_state = EscrowState::Complete;
         state.serialize(&mut &mut **state_info.data.borrow_mut())?;
     }