Require CBlockIndex::GetUndoPos() to hold mutex cs_main

jonatack · jonatack · commit 572393448b4d · 2022-01-25T20:43:22.000+01:00
diff --git a/src/chain.h b/src/chain.h
@@ -237,8 +237,9 @@ class CBlockIndex
         return ret;
     }
 
-    FlatFilePos GetUndoPos() const
+    FlatFilePos GetUndoPos() const EXCLUSIVE_LOCKS_REQUIRED(::cs_main)
     {
+        AssertLockHeld(::cs_main);
         FlatFilePos ret;
         if (nStatus & BLOCK_HAVE_UNDO) {
             ret.nFile = nFile;
diff --git a/src/node/blockstorage.cpp b/src/node/blockstorage.cpp
@@ -513,7 +513,8 @@ static bool UndoWriteToDisk(const CBlockUndo& blockundo, FlatFilePos& pos, const
 
 bool UndoReadFromDisk(CBlockUndo& blockundo, const CBlockIndex* pindex)
 {
-    FlatFilePos pos = pindex->GetUndoPos();
+    const FlatFilePos pos{WITH_LOCK(::cs_main, return pindex->GetUndoPos())};
+
     if (pos.IsNull()) {
         return error("%s: no undo data available", __func__);
     }

Original file line number	Diff line number	Diff line change
`@@ -237,8 +237,9 @@ class CBlockIndex`
`237`	`237`	`return ret;`
`238`	`238`	`}`
`239`	`239`
`240`		`- FlatFilePos GetUndoPos() const`
	`240`	`+ FlatFilePos GetUndoPos() const EXCLUSIVE_LOCKS_REQUIRED(::cs_main)`
`241`	`241`	`{`
	`242`	`+ AssertLockHeld(::cs_main);`
`242`	`243`	`FlatFilePos ret;`
`243`	`244`	`if (nStatus & BLOCK_HAVE_UNDO) {`
`244`	`245`	`ret.nFile = nFile;`
Original file line number	Diff line number	Diff line change
`@@ -513,7 +513,8 @@ static bool UndoWriteToDisk(const CBlockUndo& blockundo, FlatFilePos& pos, const`
`513`	`513`
`514`	`514`	`bool UndoReadFromDisk(CBlockUndo& blockundo, const CBlockIndex* pindex)`
`515`	`515`	`{`
`516`		`- FlatFilePos pos = pindex->GetUndoPos();`
	`516`	`+ const FlatFilePos pos{WITH_LOCK(::cs_main, return pindex->GetUndoPos())};`
	`517`	`+`
`517`	`518`	`if (pos.IsNull()) {`
`518`	`519`	`return error("%s: no undo data available", __func__);`
`519`	`520`	`}`