Re: [PATCH v2 15/25] security: call evm fscaps hooks from generic security hooks

Paul Moore
2024-02-22T00:37:15Z

On Wed, Feb 21, 2024 at 7:20 PM Seth Forshee (DigitalOcean)
<sforshee@kernel.org> wrote:
> On Wed, Feb 21, 2024 at 06:43:43PM -0500, Paul Moore wrote:
> > On Wed, Feb 21, 2024 at 4:25 PM Seth Forshee (DigitalOcean)
> > <sforshee@kernel.org> wrote:
> > >
> > > Signed-off-by: Seth Forshee (DigitalOcean) <sforshee@kernel.org>
> > > ---
> > > security/security.c | 15 +++++++++++++--
> > > 1 file changed, 13 insertions(+), 2 deletions(-)
> >
> > First off, you've got to write *something* for the commit description,
> > even if it is just a single sentence.
> >
> > > diff --git a/security/security.c b/security/security.c
> > > index 0d210da9862c..f515d8430318 100644
> > > --- a/security/security.c
> > > +++ b/security/security.c
> > > @@ -2365,9 +2365,14 @@ int security_inode_remove_acl(struct mnt_idmap *idmap,
> > > int security_inode_set_fscaps(struct mnt_idmap *idmap, struct dentry *dentry,
> > > const struct vfs_caps *caps, int flags)
> > > {
> > > + int ret;
> > > +
> > > if (unlikely(IS_PRIVATE(d_backing_inode(dentry))))
> > > return 0;
> > > - return call_int_hook(inode_set_fscaps, 0, idmap, dentry, caps, flags);
> > > + ret = call_int_hook(inode_set_fscaps, 0, idmap, dentry, caps, flags);
> > > + if (ret)
> > > + return ret;
> > > + return evm_inode_set_fscaps(idmap, dentry, caps, flags);
> > > }
> > >
> > > /**
> > > @@ -2387,6 +2392,7 @@ void security_inode_post_set_fscaps(struct mnt_idmap *idmap,
> > > if (unlikely(IS_PRIVATE(d_backing_inode(dentry))))
> > > return;
> > > call_void_hook(inode_post_set_fscaps, idmap, dentry, caps, flags);
> > > + evm_inode_post_set_fscaps(idmap, dentry, caps, flags);
> > > }
> > >
> > > /**
> > > @@ -2415,9 +2421,14 @@ int security_inode_get_fscaps(struct mnt_idmap *idmap, struct dentry *dentry)
> > > */
> > > int security_inode_remove_fscaps(struct mnt_idmap *idmap, struct dentry *dentry)
> > > {
> > > + int ret;
> > > +
> > > if (unlikely(IS_PRIVATE(d_backing_inode(dentry))))
> > > return 0;
> > > - return call_int_hook(inode_remove_fscaps, 0, idmap, dentry);
> > > + ret = call_int_hook(inode_remove_fscaps, 0, idmap, dentry);
> > > + if (ret)
> > > + return ret;
> > > + return evm_inode_remove_fscaps(dentry);
> > > }
> >
> > If you take a look at linux-next or the LSM tree's dev branch you'll
> > see that we've gotten rid of the dedicated IMA and EVM hooks,
> > promoting both IMA and EVM to "proper" LSMs that leverage the existing
> > LSM hook infrastructure. In this patchset, and moving forward, please
> > don't add dedicated IMA/EVM hooks like this, instead register them as
> > LSM hook implementations with LSM_HOOK_INIT().
>
> Yeah, I'm aware that work was going on and got applied recently. I've
> been assuming this change will go in through the vfs tree though, and I
> wasn't sure how you and Al/Christian would want to handle that
> dependency between your trees, so I held off on updating based off the
> LSM tree. I'm happy to update this for the next round though.

Okay, good, I just wanted to make sure you were aware of the changes.
Since the merge window is only a couple of weeks away I'm guessing
this isn't something we'll need to worry about in Linus' tree as the
LSM/IMA/EVM changes are slated to go up during the next merge window
and I'm guessing this will likely go in after that, targeting the
following merge window at the earliest.

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