From e497b5c5bae2a4b147ee1615ba17bc0c84f3dc1c Mon Sep 17 00:00:00 2001
From: Damian Gryski <damian@gryski.com>
Date: Fri, 28 Jan 2022 13:25:42 -0800
Subject: [PATCH] src/runtime: prevent out-of-bounds memory access during
 b.state()

---
 src/runtime/gc_conservative.go | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/runtime/gc_conservative.go b/src/runtime/gc_conservative.go
index 09c6388a..ae675be1 100644
--- a/src/runtime/gc_conservative.go
+++ b/src/runtime/gc_conservative.go
@@ -134,7 +134,7 @@ func (b gcBlock) findNext() gcBlock {
 	if b.state() == blockStateHead || b.state() == blockStateMark {
 		b++
 	}
-	for b.state() == blockStateTail {
+	for b.address() < uintptr(metadataStart) && b.state() == blockStateTail {
 		b++
 	}
 	return b