Merge bitcoin/bitcoin#26130: Bugfix: Wallet: Lock cs_wallet for SignMessage

a60d9eb Bugfix: Wallet: Lock cs_wallet for SignMessage (Luke Dashjr)

Pull request description:

  cs_desc_main is typically locked within scope of a cs_wallet lock, but:

  CWallet::IsLocked locks cs_wallet
  ...called from DescriptorScriptPubKeyMan::GetKeys
  ...called from DescriptorScriptPubKeyMan::GetSigningProvider which locks cs_desc_main first, but has no access to cs_wallet ...called from DescriptorScriptPubKeyMan::SignMessage ...called from CWallet::SignMessage which can access and lock cs_wallet

  Resolve the out of order locks by grabbing cs_wallet in CWallet::SignMessage first

  -------------

  Note this is currently only an issue for the GUI (which lacks sufficient testing apparently), but can be reproduced by #26082 (CI fails as a result)

ACKs for top commit:
  achow101:
    ACK a60d9eb
  w0xlt:
    ACK bitcoin/bitcoin@a60d9eb

Tree-SHA512: 60f6959b0ceaf4d9339ba1a47154734034b637c41b1f9e26748a2dbbc3a2a95fc3696019103c55ae70c91d910ba8f3d7f4e27d263030eb60b689f290c4d82ea9

Author: MacroFake

src/wallet/wallet.cpp

@@ -2110,6 +2110,7 @@ SigningResult CWallet::SignMessage(const std::string& message, const PKHash& pkh
     CScript script_pub_key = GetScriptForDestination(pkhash);
     for (const auto& spk_man_pair : m_spk_managers) {
         if (spk_man_pair.second->CanProvide(script_pub_key, sigdata)) {
+            LOCK(cs_wallet);  // DescriptorScriptPubKeyMan calls IsLocked which can lock cs_wallet in a deadlocking order
             return spk_man_pair.second->SignMessage(message, pkhash, str_sig);
         }
     }