[PATCH 3/8] audit: Implement audit_log_tty()

[Stefan Berger <stefanb@xxxxxxxxxxxxxxxxxx>]

Implement audit_log_tty() so that IMA can add tty= to its audit records.

Signed-off-by: Stefan Berger <stefanb@xxxxxxxxxxxxxxxxxx>
---
 include/linux/audit.h | 5 +++++
 kernel/audit.c        | 8 ++++++++
 2 files changed, 13 insertions(+)

diff --git a/include/linux/audit.h b/include/linux/audit.h
index 90aa63ddc9be..2deb76c74d10 100644
--- a/include/linux/audit.h
+++ b/include/linux/audit.h
@@ -154,6 +154,7 @@ extern void audit_log_task_info(struct audit_buffer *ab,
 				struct task_struct *tsk);
 
 extern int		    audit_update_lsm_rules(void);
+extern void audit_log_tty(struct audit_buffer *ab, struct task_struct *tsk);
 
 				/* Private API (for audit.c only) */
 extern int audit_rule_change(int type, int seq, void *data, size_t datasz);
@@ -202,6 +203,10 @@ static inline int audit_log_task_context(struct audit_buffer *ab)
 static inline void audit_log_task_info(struct audit_buffer *ab,
 				       struct task_struct *tsk)
 { }
+
+static inline void audit_log_tty(struct audit_buffer *ab,
+				 struct task_struct *tsk)
+{ }
 #define audit_enabled 0
 #endif /* CONFIG_AUDIT */
 
diff --git a/kernel/audit.c b/kernel/audit.c
index 670665c6e2a6..fa54695962b4 100644
--- a/kernel/audit.c
+++ b/kernel/audit.c
@@ -2305,6 +2305,14 @@ void audit_log_task_info(struct audit_buffer *ab, struct task_struct *tsk)
 }
 EXPORT_SYMBOL(audit_log_task_info);
 
+void audit_log_tty(struct audit_buffer *ab, struct task_struct *tsk)
+{
+	struct tty_struct *tty = audit_get_tty(tsk);
+
+	audit_log_format(ab, " tty=%s", tty ? tty_name(tty) : "(none)");
+	audit_put_tty(tty);
+}
+
 /**
  * audit_log_link_denied - report a link restriction denial
  * @operation: specific link operation
-- 
2.13.6