1 files changed, 28 insertions, 0 deletions
diff --git a/libsandbox/wrapper-funcs/openat_pre_check.c b/libsandbox/wrapper-funcs/openat_pre_check.c
new file mode 100644
index 0000000..7f5e823
--- /dev/null
+++ b/libsandbox/wrapper-funcs/openat_pre_check.c
@@ -0,0 +1,28 @@
+/*
+ * open*() pre-check.
+ *
+ * Copyright 1999-2009 Gentoo Foundation
+ * Licensed under the GPL-2
+ */
+
+bool sb_openat_pre_check(const char *func, const char *pathname, int dirfd, int flags)
+{
+	if (!(flags & O_CREAT)) {
+		/* If we're not trying to create, fail normally if
+		 * file does not stat
+		 */
+		if (dirfd == AT_FDCWD || pathname[0] == '/') {
+			struct stat st;
+			save_errno();
+			if (-1 == stat(pathname, &st)) {
+				if (is_env_on(ENV_SANDBOX_DEBUG))
+					SB_EINFO("EARLY FAIL", "  %s(%s): %s\n",
+						func, pathname, strerror(errno));
+				return false;
+			}
+			restore_errno();
+		}
+	}
+
+	return true;
+}