Re: [PATCH v2 3/3] ima: show rules with IMA_INMASK correctly

[Mimi Zohar <zohar@linux.ibm.com>]

On Wed, 2019-05-29 at 15:30 +0200, Roberto Sassu wrote:
> Show the '^' character when a policy rule has flag IMA_INMASK.
> 
> Fixes: 80eae209d63ac ("IMA: allow reading back the current IMA policy")
> Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com>
> Cc: stable@vger.kernel.org

Thanks, queued.

> ---
>  security/integrity/ima/ima_policy.c | 21 ++++++++++++---------
>  1 file changed, 12 insertions(+), 9 deletions(-)
> 
> diff --git a/security/integrity/ima/ima_policy.c b/security/integrity/ima/ima_policy.c
> index e0cc323f948f..ae4034f041c4 100644
> --- a/security/integrity/ima/ima_policy.c
> +++ b/security/integrity/ima/ima_policy.c
> @@ -1146,10 +1146,10 @@ enum {
>  };
>  
>  static const char *const mask_tokens[] = {
> -	"MAY_EXEC",
> -	"MAY_WRITE",
> -	"MAY_READ",
> -	"MAY_APPEND"
> +	"^MAY_EXEC",
> +	"^MAY_WRITE",
> +	"^MAY_READ",
> +	"^MAY_APPEND"
>  };
>  
>  #define __ima_hook_stringify(str)	(#str),
> @@ -1209,6 +1209,7 @@ int ima_policy_show(struct seq_file *m, void *v)
>  	struct ima_rule_entry *entry = v;
>  	int i;
>  	char tbuf[64] = {0,};
> +	int offset = 0;
>  
>  	rcu_read_lock();
>  
> @@ -1232,15 +1233,17 @@ int ima_policy_show(struct seq_file *m, void *v)
>  	if (entry->flags & IMA_FUNC)
>  		policy_func_show(m, entry->func);
>  
> -	if (entry->flags & IMA_MASK) {
> +	if ((entry->flags & IMA_MASK) || (entry->flags & IMA_INMASK)) {
> +		if (entry->flags & IMA_MASK)
> +			offset = 1;
>  		if (entry->mask & MAY_EXEC)
> -			seq_printf(m, pt(Opt_mask), mt(mask_exec));
> +			seq_printf(m, pt(Opt_mask), mt(mask_exec) + offset);
>  		if (entry->mask & MAY_WRITE)
> -			seq_printf(m, pt(Opt_mask), mt(mask_write));
> +			seq_printf(m, pt(Opt_mask), mt(mask_write) + offset);
>  		if (entry->mask & MAY_READ)
> -			seq_printf(m, pt(Opt_mask), mt(mask_read));
> +			seq_printf(m, pt(Opt_mask), mt(mask_read) + offset);
>  		if (entry->mask & MAY_APPEND)
> -			seq_printf(m, pt(Opt_mask), mt(mask_append));
> +			seq_printf(m, pt(Opt_mask), mt(mask_append) + offset);
>  		seq_puts(m, " ");
>  	}
>