[PATCH] init/initramfs.c: check the return value of kstrdup()

From: xkernel.wang@foxmail.com
To: linux@dominikbrodowski.net, akpm@linux-foundation.org,
	pombredanne@nexb.com, gregkh@linuxfoundation.org, arnd@arndb.de,
	luc.vanoostenryck@gmail.com
Cc: linux-kernel@vger.kernel.org, Xiaoke Wang <xkernel.wang@foxmail.com>
Subject: [PATCH] init/initramfs.c: check the return value of kstrdup()
Date: Fri,  4 Mar 2022 17:27:34 +0800	[thread overview]
Message-ID: <tencent_DE1C3D1422E1DD4A35FFDE2048CC48B94E08@qq.com> (raw)

From: Xiaoke Wang <xkernel.wang@foxmail.com>

kstrdup() is also a memory allocation function which is similar
with kmalloc() in some way. Once some internal memory errors
happen, it will return NULL. It is better to check the return
value of it so to catch the memory error in time.

Signed-off-by: Xiaoke Wang <xkernel.wang@foxmail.com>
---
 init/initramfs.c | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/init/initramfs.c b/init/initramfs.c
index a842c05..49deffb 100644
--- a/init/initramfs.c
+++ b/init/initramfs.c
@@ -139,8 +139,12 @@ static void __init dir_add(const char *name, time64_t mtime)
 	struct dir_entry *de = kmalloc(sizeof(struct dir_entry), GFP_KERNEL);
 	if (!de)
 		panic_show_mem("can't allocate dir_entry buffer");
-	INIT_LIST_HEAD(&de->list);
 	de->name = kstrdup(name, GFP_KERNEL);
+	if (!de->name) {
+		kfree(de);
+		panic_show_mem("can't duplicate dir name");
+	}
+	INIT_LIST_HEAD(&de->list);
 	de->mtime = mtime;
 	list_add(&de->list, &dir_list);
 }
-- 
