Re: [PATCH 3/8] ima: simplify conditional statement to improve performance

From: Mimi Zohar
Date: Wed Sep 03 2014 - 09:00:30 EST


On Wed, 2014-09-03 at 10:19 +0300, Dmitry Kasatkin wrote:
> Precede bit testing before string comparison makes code
> faster. Also refactor statement as a single line pointer
> assignment.
>
> Signed-off-by: Dmitry Kasatkin <d.kasatkin@xxxxxxxxxxx>

Functionally the code hasn't change, but the resulting conditional
statement isn't as clear, at least to me, as the original code. Please
include here in the patch description a short explanation of what the
code is doing.

thanks,

Mimi

> ---
> security/integrity/ima/ima_main.c | 6 ++----
> 1 file changed, 2 insertions(+), 4 deletions(-)
>
> diff --git a/security/integrity/ima/ima_main.c b/security/integrity/ima/ima_main.c
> index f82cf9b..f7b85bf 100644
> --- a/security/integrity/ima/ima_main.c
> +++ b/security/integrity/ima/ima_main.c
> @@ -206,10 +206,8 @@ static int process_measurement(struct file *file, const char *filename,
> }
>
> template_desc = ima_template_desc_current();
> - if (strcmp(template_desc->name, IMA_TEMPLATE_IMA_NAME) == 0) {
> - if (action & IMA_APPRAISE_SUBMASK)
> - xattr_ptr = &xattr_value;
> - } else
> + if ((action & IMA_APPRAISE_SUBMASK) ||
> + strcmp(template_desc->name, IMA_TEMPLATE_IMA_NAME) != 0)
> xattr_ptr = &xattr_value;
>
> rc = ima_collect_measurement(iint, file, xattr_ptr, &xattr_len);


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