Re: [PATCH 03/28] ima: Align ima_post_create_tmpfile() definition with LSM infrastructure

[Mimi Zohar]

Hi Roberto,

On Fri, 2023-03-03 at 19:18 +0100, Roberto Sassu wrote:
> From: Roberto Sassu <roberto.sassu@xxxxxxxxxx>
> 
> Change ima_post_create_tmpfile() definition, so that it can be registered
> as implementation of the post_create_tmpfile hook.

Since neither security_create_tmpfile() nor
security_post_create_tmpfile() already exist, why not pass a pointer to
the file to conform to the other file related security hooks?

Mimi

> 
> Signed-off-by: Roberto Sassu <roberto.sassu@xxxxxxxxxx>
> ---
>  fs/namei.c                        | 2 +-
>  include/linux/ima.h               | 7 +++++--
>  security/integrity/ima/ima_main.c | 8 ++++++--
>  3 files changed, 12 insertions(+), 5 deletions(-)
> 
> diff --git a/fs/namei.c b/fs/namei.c
> index b5a1ec29193..57727a1ae38 100644
> --- a/fs/namei.c
> +++ b/fs/namei.c
> @@ -3622,7 +3622,7 @@ static int vfs_tmpfile(struct mnt_idmap *idmap,
>  		inode->i_state |= I_LINKABLE;
>  		spin_unlock(&inode->i_lock);
>  	}
> -	ima_post_create_tmpfile(idmap, inode);
> +	ima_post_create_tmpfile(idmap, dir, file_dentry(file), mode);
>  	return 0;
>  }
>  
> diff --git a/include/linux/ima.h b/include/linux/ima.h
> index 179ce52013b..7535686a403 100644
> --- a/include/linux/ima.h
> +++ b/include/linux/ima.h
> @@ -19,7 +19,8 @@ extern enum hash_algo ima_get_current_hash_algo(void);
>  extern int ima_bprm_check(struct linux_binprm *bprm);
>  extern int ima_file_check(struct file *file, int mask);
>  extern void ima_post_create_tmpfile(struct mnt_idmap *idmap,
> -				    struct inode *inode);
> +				    struct inode *dir, struct dentry *dentry,
> +				    umode_t mode);
>  extern void ima_file_free(struct file *file);
>  extern int ima_file_mmap(struct file *file, unsigned long reqprot,
>  			 unsigned long prot, unsigned long flags);
> @@ -69,7 +70,9 @@ static inline int ima_file_check(struct file *file, int mask)
>  }
>  
>  static inline void ima_post_create_tmpfile(struct mnt_idmap *idmap,
> -					   struct inode *inode)
> +					   struct inode *dir,
> +					   struct dentry *dentry,
> +					   umode_t mode)
>  {
>  }
>  
> diff --git a/security/integrity/ima/ima_main.c b/security/integrity/ima/ima_main.c
> index 8941305376b..4a3d0c8bcba 100644
> --- a/security/integrity/ima/ima_main.c
> +++ b/security/integrity/ima/ima_main.c
> @@ -659,16 +659,20 @@ EXPORT_SYMBOL_GPL(ima_inode_hash);
>  /**
>   * ima_post_create_tmpfile - mark newly created tmpfile as new
>   * @idmap: idmap of the mount the inode was found from
> - * @inode: inode of the newly created tmpfile
> + * @dir: inode structure of the parent of the new file
> + * @dentry: dentry structure of the new file
> + * @mode: mode of the new file
>   *
>   * No measuring, appraising or auditing of newly created tmpfiles is needed.
>   * Skip calling process_measurement(), but indicate which newly, created
>   * tmpfiles are in policy.
>   */
>  void ima_post_create_tmpfile(struct mnt_idmap *idmap,
> -			     struct inode *inode)
> +			     struct inode *dir, struct dentry *dentry,
> +			     umode_t mode)
>  {
>  	struct integrity_iint_cache *iint;
> +	struct inode *inode = dentry->d_inode;
>  	int must_appraise;
>  
>  	if (!ima_policy_flag || !S_ISREG(inode->i_mode))