From 1b9376feda2a17f1dd728bc4ee2117f3b2cde567 Mon Sep 17 00:00:00 2001
From: Kai Tietz <ktietz70@googlemail.com>
Date: Thu, 29 Dec 2011 14:44:40 +0100
Subject: [PATCH 2/7] msvcrt: Use LOCK_ENV locking in _chdrive and do
 validatation of input argument.

---
 dlls/msvcrt/dir.c       |   19 +++++++++++++++----
 dlls/msvcrt/tests/dir.c |   23 +++++++++++++++++++++++
 2 files changed, 38 insertions(+), 4 deletions(-)

diff --git a/dlls/msvcrt/dir.c b/dlls/msvcrt/dir.c
index 44802b3..3b9e3c7 100644
--- a/dlls/msvcrt/dir.c
+++ b/dlls/msvcrt/dir.c
@@ -365,14 +365,25 @@ int CDECL MSVCRT__chdrive(int newdrive)
 {
   WCHAR buffer[] = {'A', ':', 0};
 
+  if (newdrive < 1 || newdrive > 31)
+  {
+    *MSVCRT___doserrno () = ERROR_INVALID_DRIVE;
+    *MSVCRT__errno () = MSVCRT_EACCES;
+    return -1;
+  }
   buffer[0] += newdrive - 1;
-  if (!SetCurrentDirectoryW( buffer ))
+
+  _lock (_ENV_LOCK);
+
+  if (!SetCurrentDirectoryW (buffer))
   {
-    msvcrt_set_errno(GetLastError());
-    if (newdrive <= 0)
-      *MSVCRT__errno() = MSVCRT_EACCES;
+    msvcrt_set_errno (GetLastError ());
+    _unlock (_ENV_LOCK);
     return -1;
   }
+
+  _unlock (_ENV_LOCK);
+
   return 0;
 }
 
diff --git a/dlls/msvcrt/tests/dir.c b/dlls/msvcrt/tests/dir.c
index 6cc81d1..e0e4122 100644
--- a/dlls/msvcrt/tests/dir.c
+++ b/dlls/msvcrt/tests/dir.c
@@ -40,6 +40,7 @@ static int (__cdecl *p_wmkdir)(const wchar_t *);
 static int (__cdecl *p_rmdir)(const char *);
 static int (__cdecl *p_wrmdir)(const wchar_t *);
 static int (__cdecl *p_getdrive)(void);
+static int (__cdecl *p_chdrive)(int);
 
 static void init(void)
 {
@@ -55,6 +56,8 @@ static void init(void)
     p_rmdir = (void *)GetProcAddress(hmod, "_rmdir");
     p_wrmdir = (void *)GetProcAddress(hmod, "_wrmdir");
     p_getdrive = (void *)GetProcAddress(hmod, "_getdrive");
+
+    p_chdrive = (void*)GetProcAddress(hmod,"_chdrive");
 }
 
 typedef struct
@@ -555,6 +558,25 @@ static void test_chmkrmdirA (void)
     }
 }
 
+static void test_chdrive(void)
+{
+   if (!p_getdrive || !p_chdrive)
+   {
+     win_skip("_getdrive/_chdrive not present.\n");
+   }
+   else
+   {
+     int drive = _getdrive();
+
+     errno = 0;
+     ok((p_chdrive(0) == -1 && errno == EACCES
+         && _doserrno == ERROR_INVALID_DRIVE), "Check that drive-letter < 'A' is invalid (%u)", EACCES);
+     ok((p_chdrive(32) == -1 && errno == EACCES
+	 && _doserrno == ERROR_INVALID_DRIVE), "Check that drive-letter > '_' is invalid (%u), EACCES);
+     ok((p_chdrive(drive) == 0, "Reset current drive %c", ('A' + drive - 1));
+   }
+}
+
 START_TEST(dir)
 {
     init();
@@ -563,4 +585,5 @@ START_TEST(dir)
     test_makepath();
     test_makepath_s();
     test_chmkrmdirA();
+    test_chdrive();
 }
-- 
1.7.9