net: fix use-after-free in tests

vasild · vasild · commit 7d8e1dec3b26 · 2020-03-18T13:03:26.000+01:00
In PeerLogicValidation::PeerLogicValidation() we would schedule a lambda function to execute later, capturing the local variable `consensusParams` by reference. Presumably this was considered safe because `consensusParams` is a reference itself to a global variable which is not supposed to change, but it can in tests. Fixes #18372
diff --git a/src/net_processing.cpp b/src/net_processing.cpp
@@ -1127,7 +1127,7 @@ PeerLogicValidation::PeerLogicValidation(CConnman* connmanIn, BanMan* banman, CS
     // combine them in one function and schedule at the quicker (peer-eviction)
     // timer.
     static_assert(EXTRA_PEER_CHECK_INTERVAL < STALE_CHECK_INTERVAL, "peer eviction timer should be less than stale tip check timer");
-    scheduler.scheduleEvery([&] { this->CheckForStaleTipAndEvictPeers(consensusParams); }, std::chrono::seconds{EXTRA_PEER_CHECK_INTERVAL});
+    scheduler.scheduleEvery([this, consensusParams] { this->CheckForStaleTipAndEvictPeers(consensusParams); }, std::chrono::seconds{EXTRA_PEER_CHECK_INTERVAL});
 }
 
 /**

Original file line number	Diff line number	Diff line change
`@@ -1127,7 +1127,7 @@ PeerLogicValidation::PeerLogicValidation(CConnman* connmanIn, BanMan* banman, CS`
`1127`	`1127`	`// combine them in one function and schedule at the quicker (peer-eviction)`
`1128`	`1128`	`// timer.`
`1129`	`1129`	`static_assert(EXTRA_PEER_CHECK_INTERVAL < STALE_CHECK_INTERVAL, "peer eviction timer should be less than stale tip check timer");`
`1130`		`- scheduler.scheduleEvery([&] { this->CheckForStaleTipAndEvictPeers(consensusParams); }, std::chrono::seconds{EXTRA_PEER_CHECK_INTERVAL});`
	`1130`	`+ scheduler.scheduleEvery([this, consensusParams] { this->CheckForStaleTipAndEvictPeers(consensusParams); }, std::chrono::seconds{EXTRA_PEER_CHECK_INTERVAL});`
`1131`	`1131`	`}`
`1132`	`1132`
`1133`	`1133`	`/**`