Re-enable aliasing of CodedInputStream during deserialization, removed as part of primary codepath somewhere around https://github.com/bazelbuild/bazel/commit/bde43ec8a96a62b8fbf67ad60d5154cf121647d9 (and killed entirely in unknown commit.

Force copying of a ByteString read from CodedInputStream in NestedSetCodec and persisted, since otherwise we might hang onto the entire buffer indefinitely.

PiperOrigin-RevId: 190256337

1 files changed, 5 insertions, 1 deletions

diff --git a/src/main/java/com/google/devtools/build/lib/collect/nestedset/NestedSetCodec.java b/src/main/java/com/google/devtools/build/lib/collect/nestedset/NestedSetCodec.java
index b8d8a2207e..ba170820b3 100644
--- a/src/main/java/com/google/devtools/build/lib/collect/nestedset/NestedSetCodec.java
+++ b/src/main/java/com/google/devtools/build/lib/collect/nestedset/NestedSetCodec.java
@@ -177,7 +177,11 @@ public class NestedSetCodec<T> implements ObjectCodec<NestedSet<T>> {
     // will point at the same object in memory instead of duplicating them.  Unfortunately, we had
     // to do the work of deserializing the member that we will now throw away, in order to ensure
     // that the pointer in the codedIn buffer was incremented appropriately.
-    Object oldValue = digestToChild.putIfAbsent(digest, result);
+    Object oldValue =
+        digestToChild.putIfAbsent(
+            // Copy the ByteString to avoid keeping the full buffer from codedIn alive due to
+            // aliasing.
+            ByteString.copyFrom(digest.asReadOnlyByteBuffer()), result);
     return oldValue == null ? result : oldValue;
   }