Re: [PATCH 20/28] security: Introduce inode_post_set_acl hook

[Stefan Berger <stefanb@xxxxxxxxxxxxx>]

On 3/3/23 13:18, Roberto Sassu wrote:
> From: Roberto Sassu <roberto.sassu@xxxxxxxxxx>
>
> In preparation for moving IMA and EVM to the LSM infrastructure, introduce
> the inode_post_set_acl hook.
>
> Signed-off-by: Roberto Sassu <roberto.sassu@xxxxxxxxxx>
> ---
>   fs/posix_acl.c                |  1 +
>   include/linux/lsm_hook_defs.h |  2 ++
>   include/linux/security.h      |  7 +++++++
>   security/security.c           | 17 +++++++++++++++++
>   4 files changed, 27 insertions(+)
>
> diff --git a/fs/posix_acl.c b/fs/posix_acl.c
> index 5a76fb35923..acddf2dff4c 100644
> --- a/fs/posix_acl.c
> +++ b/fs/posix_acl.c
> @@ -1102,6 +1102,7 @@ int vfs_set_acl(struct mnt_idmap *idmap, struct dentry *dentry,
>   		error = -EOPNOTSUPP;
>   	if (!error) {
>   		fsnotify_xattr(dentry);
> +		security_inode_post_set_acl(dentry, acl_name, kacl);
>   		evm_inode_post_set_acl(dentry, acl_name, kacl);
>   	}
>   
> diff --git a/include/linux/lsm_hook_defs.h b/include/linux/lsm_hook_defs.h
> index 5dc2a7c3d9a..9a3e14db0af 100644
> --- a/include/linux/lsm_hook_defs.h
> +++ b/include/linux/lsm_hook_defs.h
> @@ -156,6 +156,8 @@ LSM_HOOK(void, LSM_RET_VOID, inode_post_removexattr, struct dentry *dentry,
>   	 const char *name)
>   LSM_HOOK(int, 0, inode_set_acl, struct mnt_idmap *idmap,
>   	 struct dentry *dentry, const char *acl_name, struct posix_acl *kacl)
> +LSM_HOOK(void, LSM_RET_VOID, inode_post_set_acl, struct dentry *dentry,
> +	 const char *acl_name, struct posix_acl *kacl)
>   LSM_HOOK(int, 0, inode_get_acl, struct mnt_idmap *idmap,
>   	 struct dentry *dentry, const char *acl_name)
>   LSM_HOOK(int, 0, inode_remove_acl, struct mnt_idmap *idmap,
> diff --git a/include/linux/security.h b/include/linux/security.h
> index b3e201404dc..b0691bf7237 100644
> --- a/include/linux/security.h
> +++ b/include/linux/security.h
> @@ -366,6 +366,8 @@ int security_inode_setxattr(struct mnt_idmap *idmap,
>   int security_inode_set_acl(struct mnt_idmap *idmap,
>   			   struct dentry *dentry, const char *acl_name,
>   			   struct posix_acl *kacl);
> +void security_inode_post_set_acl(struct dentry *dentry, const char *acl_name,
> +				 struct posix_acl *kacl);
>   int security_inode_get_acl(struct mnt_idmap *idmap,
>   			   struct dentry *dentry, const char *acl_name);
>   int security_inode_remove_acl(struct mnt_idmap *idmap,
> @@ -893,6 +895,11 @@ static inline int security_inode_set_acl(struct mnt_idmap *idmap,
>   	return 0;
>   }
>   
> +static inline void security_inode_post_set_acl(struct dentry *dentry,
> +					       const char *acl_name,
> +					       struct posix_acl *kacl)
> +{ }
> +
>   static inline int security_inode_get_acl(struct mnt_idmap *idmap,
>   					 struct dentry *dentry,
>   					 const char *acl_name)
> diff --git a/security/security.c b/security/security.c
> index 8883082b686..fc11d70bb02 100644
> --- a/security/security.c
> +++ b/security/security.c
> @@ -2310,6 +2310,23 @@ int security_inode_set_acl(struct mnt_idmap *idmap,
>   	return evm_inode_set_acl(idmap, dentry, acl_name, kacl);
>   }
>   
> +/**
> + * security_inode_post_set_acl() - Update inode sec after set_acl operation

'sec' because 'security' doesn't let this fit into 80 characters for the line?

Update inode security after set_acl op     :-/
Update inode security after set_acl()      :-)

Reviewed-by: Stefan Berger <stefanb@xxxxxxxxxxxxx>