[PATCH v3] ima: Fix a potential NULL pointer access in ima_restore_measurement_list

[PATCH v3] ima: Fix a potential NULL pointer access in ima_restore_measurement_list

[Huaxin Lu]

In restore_template_fmt, when kstrdup fails, a non-NULL value will still be
returned, which causes a NULL pointer access in template_desc_init_fields.

Co-developed-by: Jiaming Li <lijiaming30@huawei.com>
Signed-off-by: Jiaming Li <lijiaming30@huawei.com>
Signed-off-by: Huaxin Lu <luhuaxin1@huawei.com>
Reviewed-by: Stefan Berger <stefanb@linux.ibm.com>
Reviewed-by: Mimi Zohar <zohar@linux.ibm.com>
---
 security/integrity/ima/ima_template.c | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/security/integrity/ima/ima_template.c b/security/integrity/ima/ima_template.c
index c25079faa..49f062692 100644
--- a/security/integrity/ima/ima_template.c
+++ b/security/integrity/ima/ima_template.c
@@ -340,8 +340,11 @@ static struct ima_template_desc *restore_template_fmt(char *template_name)
 
 	template_desc->name = "";
 	template_desc->fmt = kstrdup(template_name, GFP_KERNEL);
-	if (!template_desc->fmt)
+	if (!template_desc->fmt) {
+		kfree(template_desc);
+		template_desc = NULL;
 		goto out;
+	}
 
 	spin_lock(&template_list);
 	list_add_tail_rcu(&template_desc->list, &defined_templates);
-- 
2.36.1

Re: [PATCH v3] ima: Fix a potential NULL pointer access in ima_restore_measurement_list

[Mimi Zohar]

On Thu, 2022-11-03 at 00:09 +0800, Huaxin Lu wrote:
> In restore_template_fmt, when kstrdup fails, a non-NULL value will still be
> returned, which causes a NULL pointer access in template_desc_init_fields.
> 
> Co-developed-by: Jiaming Li <lijiaming30@huawei.com>
> Signed-off-by: Jiaming Li <lijiaming30@huawei.com>
> Signed-off-by: Huaxin Lu <luhuaxin1@huawei.com>
> Reviewed-by: Stefan Berger <stefanb@linux.ibm.com>
> Reviewed-by: Mimi Zohar <zohar@linux.ibm.com>

Thank you.   This patch is now queued in next-integrity.

-- 
Mimi