Subject: [PATCH 1/8] apparmor: just use vfs_kern_mount to make .null

From: Emanuele Giuseppe Esposito <[email-masked]>
Date: Tue, 14 Apr 2020 14:42:55 +0200

aa_mk_null_file is using simple_pin_fs/simple_release_fs with local
variables as arguments, for what would amount to a simple
vfs_kern_mount/mntput pair if everything was inlined.  Just use
the normal filesystem API since the reference counting is not needed
here.

Signed-off-by: Emanuele Giuseppe Esposito <[email-masked]>
---
 security/apparmor/apparmorfs.c | 12 ++++++------
 1 file changed, 6 insertions(+), 6 deletions(-)

diff --git a/security/apparmor/apparmorfs.c b/security/apparmor/apparmorfs.c
index 280741fc0f5f..828bb1eb77ea 100644
--- a/security/apparmor/apparmorfs.c
+++ b/security/apparmor/apparmorfs.c
@@ -2525,14 +2525,14 @@ struct path aa_null;
 
 static int aa_mk_null_file(struct dentry *parent)
 {
-	struct vfsmount *mount = NULL;
+	struct file_system_type *type = parent->d_sb->s_type;
+	struct vfsmount *mount;
 	struct dentry *dentry;
 	struct inode *inode;
-	int count = 0;
-	int error = simple_pin_fs(parent->d_sb->s_type, &mount, &count);
 
-	if (error)
-		return error;
+	mount = vfs_kern_mount(type, SB_KERNMOUNT, type->name, NULL);
+	if (IS_ERR(mount))
+		return PTR_ERR(mount);
 
 	inode_lock(d_inode(parent));
 	dentry = lookup_one_len(NULL_FILE_NAME, parent, strlen(NULL_FILE_NAME));
@@ -2561,7 +2561,7 @@ static int aa_mk_null_file(struct dentry *parent)
 	dput(dentry);
 out:
 	inode_unlock(d_inode(parent));
-	simple_release_fs(&mount, &count);
+	mntput(mount);
 	return error;
 }
 
-- 
2.25.2