[PATCH 21/28] security: Introduce inode_post_remove_acl hook

[Stefan Berger]

On 3/6/23 10:34, Roberto Sassu wrote:
> On Mon, 2023-03-06 at 10:22 -0500, Stefan Berger wrote:
>>
>> On 3/3/23 13:18, Roberto Sassu wrote:
>>> From: Roberto Sassu <roberto.sassu at huawei.com>
>>>
>>> In preparation for moving IMA and EVM to the LSM infrastructure, introduce
>>> the inode_post_remove_acl hook.
>>>
>>> Signed-off-by: Roberto Sassu <roberto.sassu at huawei.com>
>>> ---
>>>    
>>> +/**
>>> + * security_inode_post_remove_acl() - Update inode sec after remove_acl op
>>> + * @idmap: idmap of the mount
>>> + * @dentry: file
>>> + * @acl_name: acl name
>>> + *
>>> + * Update inode security field after successful remove_acl operation on @dentry
>>> + * in @idmap. The posix acls are identified by @acl_name.
>>> + */
>>> +void security_inode_post_remove_acl(struct mnt_idmap *idmap,
>>> +				    struct dentry *dentry, const char *acl_name)
>>> +{
>>> +	if (unlikely(IS_PRIVATE(d_backing_inode(dentry))))
>>> +		return;
>>
>> Was that a mistake before that EVM and IMA functions did not filtered out private inodes?
> 
> Looks like that. At least for hooks that are not called from
> security.c.

It seems like that all security_* functions are filtering on private inodes. Anonymous inodes have them and some filesystem set the S_PRIVATE flag. So it may not make a difference fro IMA and EVM then.

     Stefan

> 
> Thanks
> 
> Roberto
>