Fix memory leak in `buffer.toString("hex")` (#4235)

Co-authored-by: Jarred Sumner <709451+Jarred-Sumner@users.noreply.github.com>

2 files changed, 6 insertions, 1 deletions

diff --git a/src/bun.js/webcore/encoding.zig b/src/bun.js/webcore/encoding.zig
index 32efb3168..890dad7bd 100644
--- a/src/bun.js/webcore/encoding.zig
+++ b/src/bun.js/webcore/encoding.zig
@@ -866,12 +866,14 @@ pub const Encoder = struct {
                 }
 
                 var str = bun.String.createUninitialized(.latin1, len) orelse return ZigString.init("Out of memory").toErrorInstance(global);
+                defer str.deref();
+
                 strings.copyLatin1IntoASCII(@constCast(str.latin1()), input);
                 return str.toJS(global);
             },
             .latin1 => {
                 var str = bun.String.createUninitialized(.latin1, len) orelse return ZigString.init("Out of memory").toErrorInstance(global);
-
+                defer str.deref();
                 @memcpy(@constCast(str.latin1()), input_ptr[0..len]);
 
                 return str.toJS(global);
@@ -901,6 +903,8 @@ pub const Encoder = struct {
 
             .hex => {
                 var str = bun.String.createUninitialized(.latin1, len * 2) orelse return ZigString.init("Out of memory").toErrorInstance(global);
+                defer str.deref();
+
                 var output = @constCast(str.latin1());
                 const wrote = strings.encodeBytesToHex(output, input);
                 std.debug.assert(wrote == output.len);
diff --git a/src/js_ast.zig b/src/js_ast.zig
index 6c946b9d1..aeccdd1f3 100644
--- a/src/js_ast.zig
+++ b/src/js_ast.zig
@@ -2374,6 +2374,7 @@ pub const E = struct {
 
             if (s.is_utf16) {
                 var out = bun.String.createUninitializedUTF16(s.len());
+                defer out.deref();
                 @memcpy(@constCast(out.utf16()), s.slice16());
                 return out.toJS(globalObject);
             }