security: add ioctl specific auditing to lsm_audit

Add information about ioctl calls to the LSM audit data. Log the
file path and command number.
Signed-off-by: Jeff Vander Stoep <jeffv@google.com>
Acked-by: Nick Kralevich <nnk@google.com>
[PM: subject line tweak]
Signed-off-by: Paul Moore <pmoore@redhat.com>

include/linux/lsm_audit.h

@@ -40,6 +40,11 @@ struct lsm_network_audit {
 	} fam;
 };
 
+struct lsm_ioctlop_audit {
+	struct path path;
+	u16 cmd;
+};
+
 /* Auxiliary data to use in generating the audit record. */
 struct common_audit_data {
 	char type;
@@ -53,6 +58,7 @@ struct common_audit_data {
 #define LSM_AUDIT_DATA_KMOD	8
 #define LSM_AUDIT_DATA_INODE	9
 #define LSM_AUDIT_DATA_DENTRY	10
+#define LSM_AUDIT_DATA_IOCTL_OP	11
 	union 	{
 		struct path path;
 		struct dentry *dentry;
@@ -68,6 +74,7 @@ struct common_audit_data {
 		} key_struct;
 #endif
 		char *kmod_name;
+		struct lsm_ioctlop_audit *op;
 	} u;
 	/* this union contains LSM specific data */
 	union {

security/lsm_audit.c

@@ -245,6 +245,21 @@ static void dump_common_audit_data(struct audit_buffer *ab,
 		}
 		break;
 	}
+	case LSM_AUDIT_DATA_IOCTL_OP: {
+		struct inode *inode;
+
+		audit_log_d_path(ab, " path=", &a->u.op->path);
+
+		inode = a->u.op->path.dentry->d_inode;
+		if (inode) {
+			audit_log_format(ab, " dev=");
+			audit_log_untrustedstring(ab, inode->i_sb->s_id);
+			audit_log_format(ab, " ino=%lu", inode->i_ino);
+		}
+
+		audit_log_format(ab, " ioctlcmd=%hx", a->u.op->cmd);
+		break;
+	}
 	case LSM_AUDIT_DATA_DENTRY: {
 		struct inode *inode;