From 456a90aa1618a6c3aa49ecba46969128e2bfa26f Mon Sep 17 00:00:00 2001
From: Cherry Mui <cherryyz@google.com>
Date: Sun, 22 Jun 2025 15:01:27 -0400
Subject: [PATCH] runtime: add missing unlock in sysReserveAlignedSbrk

sysReserveAlignedSbrk locks memlock at entry, but it is not
unlocked at one of the return path. Add the missing unlock.

Fixes #74339.

Change-Id: Ib641bc348aca41494ec410e2c4eb9857f3362484
Reviewed-on: https://go-review.googlesource.com/c/go/+/683295
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: David Chase <drchase@google.com>
Reviewed-by: Michael Knyszek <mknyszek@google.com>
---
 src/runtime/mem_sbrk.go | 1 +
 1 file changed, 1 insertion(+)

diff --git a/src/runtime/mem_sbrk.go b/src/runtime/mem_sbrk.go
index 9d6842ae52..05f0fdb5d7 100644
--- a/src/runtime/mem_sbrk.go
+++ b/src/runtime/mem_sbrk.go
@@ -231,6 +231,7 @@ func sysReserveAlignedSbrk(size, align uintptr) (unsafe.Pointer, uintptr) {
 			memFree(unsafe.Pointer(end), endLen)
 		}
 		memCheck()
+		unlock(&memlock)
 		return unsafe.Pointer(pAligned), size
 	}
 
-- 
2.50.0