Merge bitcoin/bitcoin#26395: rpc: add missing lock around chainman.ActiveTip()

MacroFake · MacroFake · commit ec92d23fb892 · 2022-10-26T18:05:30.000+02:00
f5ff3d7 rpc: add missing lock around chainman.ActiveTip() (Andrew Toth) Pull request description: bitcoin/bitcoin#23927 seems to have missed a lock around `chainman.ActiveChain()`. ACKs for top commit: aureleoules: ACK f5ff3d7 Tree-SHA512: 3f116ca44c1b2bc0c7042698249ea3417dfb7c0bb81158a7ceecd087f1e02baa89948f9bb7924b1757798a1691a7de6e886aa72a0a9e227c13a3f512cc59d6c9
diff --git a/src/rpc/blockchain.cpp b/src/rpc/blockchain.cpp
@@ -461,7 +461,7 @@ static RPCHelpMan getblockfrompeer()
 
     // Fetching blocks before the node has syncing past their height can prevent block files from
     // being pruned, so we avoid it if the node is in prune mode.
-    if (index->nHeight > chainman.ActiveChain().Tip()->nHeight && node::fPruneMode) {
+    if (node::fPruneMode && index->nHeight > WITH_LOCK(chainman.GetMutex(), return chainman.ActiveTip()->nHeight)) {
         throw JSONRPCError(RPC_MISC_ERROR, "In prune mode, only blocks that the node has already synced previously can be fetched from a peer");
     }
 

Original file line number	Diff line number	Diff line change
`@@ -461,7 +461,7 @@ static RPCHelpMan getblockfrompeer()`
`461`	`461`
`462`	`462`	`// Fetching blocks before the node has syncing past their height can prevent block files from`
`463`	`463`	`// being pruned, so we avoid it if the node is in prune mode.`
`464`		`- if (index->nHeight > chainman.ActiveChain().Tip()->nHeight && node::fPruneMode) {`
	`464`	`+ if (node::fPruneMode && index->nHeight > WITH_LOCK(chainman.GetMutex(), return chainman.ActiveTip()->nHeight)) {`
`465`	`465`	`throw JSONRPCError(RPC_MISC_ERROR, "In prune mode, only blocks that the node has already synced previously can be fetched from a peer");`
`466`	`466`	`}`
`467`	`467`