Merge #16015: validation: Hold cs_main when reading chainActive in RewindBlockIndex

MarcoFalke · MarcoFalke · commit 1c177c3a004f · 2019-05-22T08:17:48.000-04:00
1609809 validation: Hold cs_main when reading chainActive in RewindBlockIndex (practicalswift) Pull request description: Fixes #15980. Hold `cs_main` when reading `chainActive` (via `::ChainActive()`) in `RewindBlockIndex`. ACKs for commit 160980: MarcoFalke: utACK 1609809 Tree-SHA512: 54f180ab391f92f04950735c2bb337f0b7495826d2096f7a0f9a2da50bc29d08747f404a0495e33ca4edd4c842efbab4c4730d5e1a8b9da3e1249cf884268f4b
diff --git a/src/validation.cpp b/src/validation.cpp
@@ -4307,6 +4307,7 @@ bool RewindBlockIndex(const CChainParams& params) {
         return false;
     }
 
+    LOCK(cs_main);
     if (::ChainActive().Tip() != nullptr) {
         // FlushStateToDisk can possibly read ::ChainActive(). Be conservative
         // and skip it here, we're about to -reindex-chainstate anyway, so

Original file line number	Diff line number	Diff line change
`@@ -4307,6 +4307,7 @@ bool RewindBlockIndex(const CChainParams& params) {`
`4307`	`4307`	`return false;`
`4308`	`4308`	`}`
`4309`	`4309`
	`4310`	`+ LOCK(cs_main);`
`4310`	`4311`	`if (::ChainActive().Tip() != nullptr) {`
`4311`	`4312`	`// FlushStateToDisk can possibly read ::ChainActive(). Be conservative`
`4312`	`4313`	`// and skip it here, we're about to -reindex-chainstate anyway, so`