On 2025-05-12 08:43:32, Casey Schaufler wrote:
> On 5/12/2025 6:25 AM, Andrey Albershteyn wrote:
> > Introduce new hooks for setting and getting filesystem extended
> > attributes on inode (FS_IOC_FSGETXATTR).
> >
> > Cc: seli...@vger.kernel.org
> > Cc: Paul Moore <p...@paul-moore.com>
> >
> > Signed-off-by: Andrey Albershteyn <aalbe...@kernel.org>
> > ---
> > fs/file_attr.c | 19 ++++++++++++++++---
> > include/linux/lsm_hook_defs.h | 2 ++
> > include/linux/security.h | 16 ++++++++++++++++
> > security/security.c | 30 ++++++++++++++++++++++++++++++
> > 4 files changed, 64 insertions(+), 3 deletions(-)
> >
> > diff --git a/fs/file_attr.c b/fs/file_attr.c
> > index 2910b7047721..be62d97cc444 100644
> > --- a/fs/file_attr.c
> > +++ b/fs/file_attr.c
> > @@ -76,10 +76,15 @@ EXPORT_SYMBOL(fileattr_fill_flags);
> > int vfs_fileattr_get(struct dentry *dentry, struct fileattr *fa)
> > {
> > struct inode *inode = d_inode(dentry);
> > + int error;
> >
> > if (!inode->i_op->fileattr_get)
> > return -ENOIOCTLCMD;
> >
> > + error = security_inode_file_getattr(dentry, fa);
> > + if (error)
> > + return error;
> > +
>
> If you're changing VFS behavior to depend on LSMs supporting the new
> hooks I'm concerned about the impact it will have on the LSMs that you
> haven't supplied hooks for. Have you tested these changes with anything
> besides SELinux?
Sorry, this thread is incomplete, I've resent full patchset again.
If you have any further comments please comment in that thread [1]
I haven't tested with anything except SELinux, but I suppose if
module won't register any hooks, then security_inode_file_*() will
return 0. Reverting SELinux implementation of the hooks doesn't
cause any errors.
I'm not that familiar with LSMs/selinux and its codebase, if you can
recommend what need to be tested while adding new hooks, I will try
to do that for next revision.
[1]:
https://lore.kernel.org/linux-fsdevel/CAOQ4uxgOAxg7N1OUJfb1KMp7oWOfN=KV9Lzz6ZrX0=xrgoq...@mail.gmail.com/T/#t
--
- Andrey
