From: Yangxi Xiang <xyangxi5@gmail.com>
Date: Mon, 27 Jun 2022 12:04:09 +0000 (+0800)
Subject: devtmpfs: fix the dangling pointer of global devtmpfsd thread
X-Git-Tag: baikal/mips/sdk6.1~5149^2~27
X-Git-Url: https://git.baikalelectronics.ru/sdk/?a=commitdiff_plain;h=ac1747e55648a6b30bc7698c4f5b9ed10b19201c;p=kernel.git

devtmpfs: fix the dangling pointer of global devtmpfsd thread

When the devtmpfs fails to mount, a dangling pointer still remains in
global. Specifically, the err variable is passed by a pointer to the
devtmpfsd. When the devtmpfsd exits, it sets the error and completes the
setup_done. In this situation, the thread pointer is not set to null.
After the devtmpfsd exited, the devtmpfs can wakes up the destroyed
devtmpfsd thread by wake_up_process if a device change event comes.

Signed-off-by: Yangxi Xiang <xyangxi5@gmail.com>
Link: https://lore.kernel.org/r/20220627120409.11174-1-xyangxi5@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---

diff --git a/drivers/base/devtmpfs.c b/drivers/base/devtmpfs.c
index 8a3ddbae3b70c..e4bffeabf344e 100644
--- a/drivers/base/devtmpfs.c
+++ b/drivers/base/devtmpfs.c
@@ -482,6 +482,7 @@ int __init devtmpfs_init(void)
 	if (err) {
 		printk(KERN_ERR "devtmpfs: unable to create devtmpfs %i\n", err);
 		unregister_filesystem(&dev_fs_type);
+		thread = NULL;
 		return err;
 	}