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SubjectRe: [PATCH] ima: fix off-by-one comparison on template name length
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Hi Colin,

On Tue, 2016-09-20 at 18:25 +0100, Colin King wrote:
> From: Colin Ian King <colin.king@canonical.com>
>
> The comparison of dr_v1->template_name_len is off-by-one, so
> currently if the length is MAX_TEMPLATE_NAME_LEN we end up
> with an out-of-bounds write on template_name when the terminating
> zero character is written. Fix the comparison.
>
> Signed-off-by: Colin Ian King <colin.king@canonical.com>

Thank you for the bug report. The patch that introduces this bug is in
the -mm tree. The next posting will include this bug fix.

Thanks!

Mimi

> ---
> security/integrity/ima/ima_template.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/security/integrity/ima/ima_template.c b/security/integrity/ima/ima_template.c
> index 24775f3..004723c 100644
> --- a/security/integrity/ima/ima_template.c
> +++ b/security/integrity/ima/ima_template.c
> @@ -395,7 +395,7 @@ int ima_restore_measurement_list(loff_t size, void *buf)
> hdr_v1->template_name_len =
> le32_to_cpu(hdr_v1->template_name_len);
>
> - if ((hdr_v1->template_name_len > MAX_TEMPLATE_NAME_LEN) ||
> + if ((hdr_v1->template_name_len >= MAX_TEMPLATE_NAME_LEN) ||
> ((bufp + hdr_v1->template_name_len) > bufendp)) {
> pr_err("attempting to restore a template name \
> that is too long\n");


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