-#ifndef _LTTNG_PROBE_USER_H
-#define _LTTNG_PROBE_USER_H
-
-/*
+/* SPDX-License-Identifier: (GPL-2.0 or LGPL-2.1)
+ *
* lttng-probe-user.h
*
* Copyright (C) 2012 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
- *
- * This library is free software; you can redistribute it and/or
- * modify it under the terms of the GNU Lesser General Public
- * License as published by the Free Software Foundation; only
- * version 2.1 of the License.
- *
- * This library is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
- * Lesser General Public License for more details.
- *
- * You should have received a copy of the GNU Lesser General Public
- * License along with this library; if not, write to the Free Software
- * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
+#ifndef _LTTNG_PROBE_USER_H
+#define _LTTNG_PROBE_USER_H
+
+#include <wrapper/uaccess.h>
+
/*
* Calculate string length. Include final null terminating character if there is
* one, or ends at first fault.
*/
long lttng_strlen_user_inatomic(const char *addr);
+/*
+ * We use __copy_from_user_inatomic to copy userspace data after
+ * checking with access_ok() and disabling page faults.
+ *
+ * Return 0 if OK, nonzero on error.
+ */
+static inline
+unsigned long lttng_copy_from_user_check_nofault(void *dest,
+ const void __user *src,
+ unsigned long len)
+{
+ unsigned long ret;
+
+ if (!lttng_access_ok(VERIFY_READ, src, len))
+ return 1;
+ pagefault_disable();
+ ret = __copy_from_user_inatomic(dest, src, len);
+ pagefault_enable();
+ return ret;
+}
+
#endif /* _LTTNG_PROBE_USER_H */