From e39af550f8ea57504510dc5d5fa70ba934f16fa0 Mon Sep 17 00:00:00 2001
From: apocelipes <seve3r@outlook.com>
Date: Wed, 20 Mar 2024 05:33:46 +0000
Subject: [PATCH] database/sql: fix memory leaks in Stmt.removeClosedStmtLocked

Zero out elements before shrinking the slice to avoid memory leaks.

Fixes #66410

Change-Id: I8f64c21455761f7f7c8b6fee0b6450b98f691d91
GitHub-Last-Rev: b15586e801199b9674f5bfcb12a848a55f15a80b
GitHub-Pull-Request: golang/go#66419
Reviewed-on: https://go-review.googlesource.com/c/go/+/572956
TryBot-Result: Gopher Robot <gobot@golang.org>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: David Chase <drchase@google.com>
Reviewed-by: Keith Randall <khr@google.com>
Reviewed-by: Emmanuel Odeke <emmanuel@orijtech.com>
Run-TryBot: Emmanuel Odeke <emmanuel@orijtech.com>
---
 src/database/sql/sql.go | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/src/database/sql/sql.go b/src/database/sql/sql.go
index b5facdbf2a..36995a1059 100644
--- a/src/database/sql/sql.go
+++ b/src/database/sql/sql.go
@@ -2684,6 +2684,8 @@ func (s *Stmt) removeClosedStmtLocked() {
 	for i := 0; i < len(s.css); i++ {
 		if s.css[i].dc.dbmuClosed {
 			s.css[i] = s.css[len(s.css)-1]
+			// Zero out the last element (for GC) before shrinking the slice.
+			s.css[len(s.css)-1] = connStmt{}
 			s.css = s.css[:len(s.css)-1]
 			i--
 		}
-- 
2.50.0