From a6bac95fbda1ef3c08034b88e2b861b96ea379f3 Mon Sep 17 00:00:00 2001
From: Julian Stecklina <js@alien8.de>
Date: Wed, 8 Feb 2012 22:57:57 +0100
Subject: [PATCH] Fix possible NULL-pointer dereference in _stat

When given NULL pointers as buffers to _stat, return EFAULT, just as
Linux and FreeBSD. Fixes #101.
---
 ports/src/lib/libc_noux/plugin.cc | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/ports/src/lib/libc_noux/plugin.cc b/ports/src/lib/libc_noux/plugin.cc
index e8e7834a3..1b7b58692 100644
--- a/ports/src/lib/libc_noux/plugin.cc
+++ b/ports/src/lib/libc_noux/plugin.cc
@@ -96,6 +96,11 @@ static void _sysio_to_stat_struct(Noux::Sysio const *sysio, struct stat *buf)
 
 static int _stat(const char *path, struct stat *buf, bool lstat = false)
 {
+	if ((path == NULL) or (buf == NULL)) {
+		errno = EFAULT;
+		return -1;
+	}
+
 	Genode::strncpy(sysio()->stat_in.path, path, sizeof(sysio()->stat_in.path));
 
 	if (!noux()->syscall(Noux::Session::SYSCALL_STAT)) {