[PATCH] fs: export anon_inode_make_secure_inode() and fix secretmem LSM bypass

[Christian Brauner]

On Thu, Jun 19, 2025 at 11:13:49AM +0200, Vlastimil Babka wrote:
> On 6/19/25 09:31, Shivank Garg wrote:
> > Export anon_inode_make_secure_inode() to allow KVM guest_memfd to create
> > anonymous inodes with proper security context. This replaces the current
> > pattern of calling alloc_anon_inode() followed by
> > inode_init_security_anon() for creating security context manually.
> > 
> > This change also fixes a security regression in secretmem where the
> > S_PRIVATE flag was not cleared after alloc_anon_inode(), causing
> > LSM/SELinux checks to be bypassed for secretmem file descriptors.
> > 
> > As guest_memfd currently resides in the KVM module, we need to export this
> 
> Could we use the new EXPORT_SYMBOL_GPL_FOR_MODULES() thingy to make this
> explicit for KVM?

Oh? Enlighten me about that, if you have a second, please.