1 files changed, 35 insertions, 0 deletions
diff --git a/src/fetch_indirect_syscall_args.c b/src/fetch_indirect_syscall_args.c
new file mode 100644
index 000000000..10d0c8474
--- /dev/null
+++ b/src/fetch_indirect_syscall_args.c
@@ -0,0 +1,35 @@
+/*
+ * Copyright (c) 2018 The strace developers.
+ * All rights reserved.
+ *
+ * SPDX-License-Identifier: LGPL-2.1-or-later
+ */
+
+#include "defs.h"
+
+/*
+ * Fetch indirect syscall arguments that are provided as an array.
+ * Return a pointer to a static array of kernel_ulong_t elements,
+ * or NULL in case of fetch failure.
+ */
+kernel_ulong_t *
+fetch_indirect_syscall_args(struct tcb *const tcp,
+			    const kernel_ulong_t addr,
+			    const unsigned int n_args)
+{
+	static kernel_ulong_t u_arg[MAX_ARGS];
+
+	if (current_wordsize == sizeof(*u_arg)) {
+		if (umoven(tcp, addr, sizeof(*u_arg) * n_args, u_arg))
+			return NULL;
+	} else {
+		uint32_t narrow_arg[ARRAY_SIZE(u_arg)];
+
+		if (umoven(tcp, addr, sizeof(*narrow_arg) * n_args, narrow_arg))
+			return NULL;
+		for (unsigned int i = 0; i < n_args; ++i)
+			u_arg[i] = narrow_arg[i];
+	}
+
+	return u_arg;
+}