gui: only call getOrCreateWallet if wallet interface pointer not null #16955

pull icota wants to merge 1 commits into bitcoin:master from icota:qt-loadwallet-crash changing 1 files +1 −1

icota commented at 2:47 PM on September 24, 2019: contributor

Avoid early call to loadwallet crashing bitcoin-qt. Meant to fix #16937.

gui: only call getOrCreateWallet if wallet interface pointer not null

Avoids early call to loadwallet crashing bitcoin-qt (https://github.com/bitcoin/bitcoin/issues/16937)

db31bcb475

in src/qt/walletcontroller.cpp:34 in db31bcb475
```
  30 | @@ -31,7 +31,7 @@ WalletController::WalletController(interfaces::Node& node, const PlatformStyle*
  31 |      , m_options_model(options_model)
  32 |  {
  33 |      m_handler_load_wallet = m_node.handleLoadWallet([this](std::unique_ptr<interfaces::Wallet> wallet) {
  34 | -        getOrCreateWallet(std::move(wallet));
  35 | +        if (wallet) getOrCreateWallet(std::move(wallet));
```
promag commented at 2:58 PM on September 24, 2019:

In what case wallet is null?

emilengler commented at 7:48 PM on September 24, 2019:

See line 95 in qt/walletcontroller.cpp There it checks if the wallet is empty even though it isn't null (I think).

icota commented at 8:18 AM on September 25, 2019:

@promag In case you call loadwallet very early in bitcoin-qt init. @fanquake has written a python script in #16937 that triggers it consistently.

promag commented at 9:31 AM on September 25, 2019:

This fix is incorrect.

icota commented at 12:12 PM on September 25, 2019:

Okay. Care to elaborate?

promag commented at 12:19 PM on September 25, 2019:

Sorry, forgot to update this, see #16963.

Note that conceptually you are being notified about a new wallet, it should exist! Also this change hides a more severe problem which is explained in my PR.

icota commented at 1:47 PM on September 25, 2019:

Thanks, closing this now in favour of #16963.
DrahtBot added the label GUI on Sep 24, 2019
icota closed this on Sep 25, 2019
DrahtBot locked this on Dec 16, 2021

Contributors

Labels

Linked (view graph)

#16937 bitcoin-qt crash after early call to loadwallet