From e60625e7ce10f696690d9e36a9f32fc7c1897f79 Mon Sep 17 00:00:00 2001
From: Thorsten Blum <thorsten.blum@linux.dev>
Date: Fri, 12 Sep 2025 08:52:57 +0200
Subject: [PATCH] initramfs: Use struct_size() helper to improve dir_add()

Use struct_size() to calculate the number of bytes to allocate for a new
directory entry.  No functional changes.

Signed-off-by: Thorsten Blum <thorsten.blum@linux.dev>
Signed-off-by: Christian Brauner <brauner@kernel.org>
---
 init/initramfs.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/init/initramfs.c b/init/initramfs.c
index 097673b97784..c607f4d681ef 100644
--- a/init/initramfs.c
+++ b/init/initramfs.c
@@ -19,6 +19,7 @@
 #include <linux/init_syscalls.h>
 #include <linux/umh.h>
 #include <linux/security.h>
+#include <linux/overflow.h>
 
 #include "do_mounts.h"
 #include "initramfs_internal.h"
@@ -152,7 +153,7 @@ static void __init dir_add(const char *name, size_t nlen, time64_t mtime)
 {
 	struct dir_entry *de;
 
-	de = kmalloc(sizeof(struct dir_entry) + nlen, GFP_KERNEL);
+	de = kmalloc(struct_size(de, name, nlen), GFP_KERNEL);
 	if (!de)
 		panic_show_mem("can't allocate dir_entry buffer");
 	INIT_LIST_HEAD(&de->list);