[v6,03/10] ima: permit duplicate measurement list entries
diff mbox

Message ID 1477017898-10375-4-git-send-email-bauerman@linux.vnet.ibm.com
State New
Headers show

Commit Message

Thiago Jung Bauermann Oct. 21, 2016, 2:44 a.m. UTC
From: Mimi Zohar <zohar@linux.vnet.ibm.com>

Measurements carried across kexec need to be added to the IMA
measurement list, but should not prevent measurements of the newly
booted kernel from being added to the measurement list. This patch
adds support for allowing duplicate measurements.

The "boot_aggregate" measurement entry is the delimiter between soft
boots.

Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
---
 security/integrity/ima/ima_queue.c | 15 +++++++++------
 1 file changed, 9 insertions(+), 6 deletions(-)

Comments

Dmitry Kasatkin Nov. 8, 2016, 7:47 p.m. UTC | #1
On Fri, Oct 21, 2016 at 5:44 AM, Thiago Jung Bauermann
<bauerman@linux.vnet.ibm.com> wrote:
> From: Mimi Zohar <zohar@linux.vnet.ibm.com>
>
> Measurements carried across kexec need to be added to the IMA
> measurement list, but should not prevent measurements of the newly
> booted kernel from being added to the measurement list. This patch
> adds support for allowing duplicate measurements.
>
> The "boot_aggregate" measurement entry is the delimiter between soft
> boots.
>
> Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
> ---
>  security/integrity/ima/ima_queue.c | 15 +++++++++------
>  1 file changed, 9 insertions(+), 6 deletions(-)
>
> diff --git a/security/integrity/ima/ima_queue.c b/security/integrity/ima/ima_queue.c
> index 4b1bb7787839..12d1b040bca9 100644
> --- a/security/integrity/ima/ima_queue.c
> +++ b/security/integrity/ima/ima_queue.c
> @@ -65,11 +65,12 @@ static struct ima_queue_entry *ima_lookup_digest_entry(u8 *digest_value,
>  }
>
>  /* ima_add_template_entry helper function:
> - * - Add template entry to measurement list and hash table.
> + * - Add template entry to the measurement list and hash table, for
> + *   all entries except those carried across kexec.
>   *
>   * (Called with ima_extend_list_mutex held.)
>   */
> -static int ima_add_digest_entry(struct ima_template_entry *entry)
> +static int ima_add_digest_entry(struct ima_template_entry *entry, int flags)
>  {
>         struct ima_queue_entry *qe;
>         unsigned int key;
> @@ -85,8 +86,10 @@ static int ima_add_digest_entry(struct ima_template_entry *entry)
>         list_add_tail_rcu(&qe->later, &ima_measurements);
>
>         atomic_long_inc(&ima_htable.len);
> -       key = ima_hash_key(entry->digest);
> -       hlist_add_head_rcu(&qe->hnext, &ima_htable.queue[key]);
> +       if (flags) {

It looks lile "bool", not flags in fact.


> +               key = ima_hash_key(entry->digest);
> +               hlist_add_head_rcu(&qe->hnext, &ima_htable.queue[key]);
> +       }
>         return 0;
>  }
>
> @@ -126,7 +129,7 @@ int ima_add_template_entry(struct ima_template_entry *entry, int violation,
>                 }
>         }
>
> -       result = ima_add_digest_entry(entry);
> +       result = ima_add_digest_entry(entry, 1);
>         if (result < 0) {
>                 audit_cause = "ENOMEM";
>                 audit_info = 0;
> @@ -155,7 +158,7 @@ int ima_restore_measurement_entry(struct ima_template_entry *entry)
>         int result = 0;
>
>         mutex_lock(&ima_extend_list_mutex);
> -       result = ima_add_digest_entry(entry);
> +       result = ima_add_digest_entry(entry, 0);
>         mutex_unlock(&ima_extend_list_mutex);
>         return result;
>  }
> --
> 2.7.4
>
>
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Patch
diff mbox

diff --git a/security/integrity/ima/ima_queue.c b/security/integrity/ima/ima_queue.c
index 4b1bb7787839..12d1b040bca9 100644
--- a/security/integrity/ima/ima_queue.c
+++ b/security/integrity/ima/ima_queue.c
@@ -65,11 +65,12 @@  static struct ima_queue_entry *ima_lookup_digest_entry(u8 *digest_value,
 }
 
 /* ima_add_template_entry helper function:
- * - Add template entry to measurement list and hash table.
+ * - Add template entry to the measurement list and hash table, for
+ *   all entries except those carried across kexec.
  *
  * (Called with ima_extend_list_mutex held.)
  */
-static int ima_add_digest_entry(struct ima_template_entry *entry)
+static int ima_add_digest_entry(struct ima_template_entry *entry, int flags)
 {
 	struct ima_queue_entry *qe;
 	unsigned int key;
@@ -85,8 +86,10 @@  static int ima_add_digest_entry(struct ima_template_entry *entry)
 	list_add_tail_rcu(&qe->later, &ima_measurements);
 
 	atomic_long_inc(&ima_htable.len);
-	key = ima_hash_key(entry->digest);
-	hlist_add_head_rcu(&qe->hnext, &ima_htable.queue[key]);
+	if (flags) {
+		key = ima_hash_key(entry->digest);
+		hlist_add_head_rcu(&qe->hnext, &ima_htable.queue[key]);
+	}
 	return 0;
 }
 
@@ -126,7 +129,7 @@  int ima_add_template_entry(struct ima_template_entry *entry, int violation,
 		}
 	}
 
-	result = ima_add_digest_entry(entry);
+	result = ima_add_digest_entry(entry, 1);
 	if (result < 0) {
 		audit_cause = "ENOMEM";
 		audit_info = 0;
@@ -155,7 +158,7 @@  int ima_restore_measurement_entry(struct ima_template_entry *entry)
 	int result = 0;
 
 	mutex_lock(&ima_extend_list_mutex);
-	result = ima_add_digest_entry(entry);
+	result = ima_add_digest_entry(entry, 0);
 	mutex_unlock(&ima_extend_list_mutex);
 	return result;
 }