[RFC PATCH 5/5] ima: Add ns_mnt, dev, ino fields to IMA audit measurement msgs

[Mehmet Kayaalp <mkayaalp@linux.vnet.ibm.com>]

From: Guilherme Magalhaes <guilherme.magalhaes@hpe.com>

Extending audit measurement record with mount namespace id, file inode,
and device name. These fields uniquely identify a pathname considering
different mount namespaces. The file inode on a given device is unique
and these fields are required to identify a namespace id since this id
can be released and later reused by a different process.

Signed-off-by: Guilherme Magalhaes <guilherme.magalhaes@hpe.com>

Changelog:
* Change the field name from "mnt_ns" to "ns_mnt"

Signed-off-by: Mehmet Kayaalp <mkayaalp@linux.vnet.ibm.com>
---
 security/integrity/ima/ima_api.c | 10 ++++++++++
 1 file changed, 10 insertions(+)

diff --git a/security/integrity/ima/ima_api.c b/security/integrity/ima/ima_api.c
index 4a77072..084b126 100644
--- a/security/integrity/ima/ima_api.c
+++ b/security/integrity/ima/ima_api.c
@@ -18,6 +18,7 @@
 #include <linux/fs.h>
 #include <linux/xattr.h>
 #include <linux/evm.h>
+#include <linux/proc_ns.h>
 
 #include "ima.h"
 
@@ -296,6 +297,7 @@ void ima_audit_measurement(struct integrity_iint_cache *iint,
 	char algo_hash[sizeof(hash) + strlen(algo_name) + 2];
 	int i;
 	unsigned long flags = iint_flags(iint, status);
+	struct ns_common *ns;
 
 	if (flags & IMA_AUDITED)
 		return;
@@ -314,6 +316,14 @@ void ima_audit_measurement(struct integrity_iint_cache *iint,
 	audit_log_format(ab, " hash=");
 	snprintf(algo_hash, sizeof(algo_hash), "%s:%s", algo_name, hash);
 	audit_log_untrustedstring(ab, algo_hash);
+	ns = mntns_operations.get(current);
+	if (!IS_ERR_OR_NULL(ns)) {
+		audit_log_format(ab, " ns_mnt=%u", ns->inum);
+		mntns_operations.put(ns);
+	}
+	audit_log_format(ab, " dev=");
+	audit_log_untrustedstring(ab, iint->inode->i_sb->s_id);
+	audit_log_format(ab, " ino=%lu", iint->inode->i_ino);
 
 	audit_log_task_info(ab, current);
 	audit_log_end(ab);
-- 
2.9.4