On Mon, May 09, 2022 at 02:54:14PM -0500, Serge Hallyn wrote: > On Wed, Apr 20, 2022 at 10:06:08AM -0400, Stefan Berger wrote: > > From: Christian Brauner <brauner@xxxxxxxxxx> > > > > When securityfs creates a new file or directory via > > securityfs_create_dentry() it will take an additional reference on the > > newly created dentry after it has attached the new inode to the new > > dentry and added it to the hashqueues. > > If we contrast this with debugfs which has the same underlying logic as > > securityfs. It uses a similar pairing as securityfs. Where securityfs > > has the securityfs_create_dentry() and securityfs_remove() pairing, > > debugfs has the __debugfs_create_file() and debugfs_remove() pairing. > > > > In contrast to securityfs, debugfs doesn't take an additional reference > > on the newly created dentry in __debugfs_create_file() which would need > > to be put in debugfs_remove(). > > > > The additional dget() isn't a problem per se. In the current > > implementation of securityfs each created dentry pins the filesystem via > > Is 'via' an extra word here or is there a missing word? > > I'll delay the rest of my response as the missing word may answer my > remaining question :) It can be both. It should either be removed or it should be followed by "securityfs_create_dentry()". securityfs_create_dentry() takes two references one in lookup_one_len() and another one explicitly via dget(). The latter one isn't needed. Some of that has been covered in an earlier thread: https://lore.kernel.org/lkml/20220105101815.ldsm4s5yx7pmuiil@wittgenstein
