On 1/13/22 15:27, Mimi Zohar wrote:

Hi Stefan,

On Tue, 2022-01-04 at 12:04 -0500, Stefan Berger wrote:

quoted

From: Stefan Berger <stefanb@linux.ibm.com>

Move measurement list related variables into the ima_namespace. This way a
front-end like SecurityFS can show the measurement list inside an IMA
namespace.

Signed-off-by: Stefan Berger <stefanb@linux.ibm.com>
---
  security/integrity/ima/ima.h             |  5 +++--
  security/integrity/ima/ima_fs.c          |  6 ++++--
  security/integrity/ima/ima_init_ima_ns.c |  5 +++++
  security/integrity/ima/ima_kexec.c       | 12 +++++++-----
  security/integrity/ima/ima_queue.c       | 24 ++++++++++--------------
  5 files changed, 29 insertions(+), 23 deletions(-)

diff --git a/security/integrity/ima/ima.h b/security/integrity/ima/ima.h
index 68d8a8e6fd1d..ee16ce5050c8 100644
--- a/security/integrity/ima/ima.h
+++ b/security/integrity/ima/ima.h

@@ -106,7 +106,6 @@ struct ima_queue_entry {
  	struct list_head later;		/* place in ima_measurements list */
  	struct ima_template_entry *entry;
  };
-extern struct list_head ima_measurements;	/* list of all measurements */
  
  /* Some details preceding the binary serialized measurement list */
  struct ima_kexec_hdr {

@@ -134,6 +133,8 @@ struct ima_namespace {
  	int ima_policy_flag;
  
  	struct ima_h_table ima_htable;
+	struct list_head ima_measurements;
+	unsigned long binary_runtime_size;

Please add a comment indicating binary_runtime_size is only applicable
to ns_ima_init.

It looks like this now:

         struct list_head ima_measurements;
         /* binary_runtime_size is used only by init_ima_ns */
         unsigned long binary_runtime_size;

quoted

  } __randomize_layout;
  extern struct ima_namespace init_ima_ns;

quoted

@@ -124,12 +119,13 @@ static int ima_add_digest_entry(struct ima_namespace *ns,
   * entire binary_runtime_measurement list, including the ima_kexec_hdr
   * structure.
   */
-unsigned long ima_get_binary_runtime_size(void)
+unsigned long ima_get_binary_runtime_size(struct ima_namespace *ns)
  {
-	if (binary_runtime_size >= (ULONG_MAX - sizeof(struct ima_kexec_hdr)))
+	if (ns->binary_runtime_size >=
+				(ULONG_MAX - sizeof(struct ima_kexec_hdr)))
  		return ULONG_MAX;
  	else
-		return binary_runtime_size + sizeof(struct ima_kexec_hdr);
+		return ns->binary_runtime_size + sizeof(struct ima_kexec_hdr);
  }
  

Please update the function description indicating that either carrying
the measurement list across kexec is limited to ns_ima_init or not
supported by namespaces.

This is the updated function description:


/*
  * Return the amount of memory required for serializing the
  * entire binary_runtime_measurement list, including the ima_kexec_hdr
  * structure. Carrying the measurement list across kexec is limited
  * to init_ima_ns.
  */

thanks,

Mimi