Erich E. Hoover : kernel32: Handle bogus DOS paths in GetVolumePathName.

[Alexandre Julliard]

Module: wine
Branch: master
Commit: 5a84969f39693ffce1f83a78ae153a1f83e20d60
URL:    http://source.winehq.org/git/wine.git/?a=commit;h=5a84969f39693ffce1f83a78ae153a1f83e20d60

Author: Erich E. Hoover <erich.e.hoover at wine-staging.com>
Date:   Mon Jun 15 22:20:03 2015 -0600

kernel32: Handle bogus DOS paths in GetVolumePathName.

Paths that are not NT and not even close to DOS don't actually fail
catastrophically.  Even though MSDN suggests that it returns the boot
drive in this case, tests indicate that it returns the drive of the
current working directory.

---

 dlls/kernel32/tests/volume.c | 22 ++++++++++++++++++----
 dlls/kernel32/volume.c       | 12 ++++++++++++
 2 files changed, 30 insertions(+), 4 deletions(-)

diff --git a/dlls/kernel32/tests/volume.c b/dlls/kernel32/tests/volume.c
index 5b117b8..7ed55d7 100644
--- a/dlls/kernel32/tests/volume.c
+++ b/dlls/kernel32/tests/volume.c
@@ -591,7 +591,7 @@ static void test_disk_extents(void)
 
 static void test_GetVolumePathNameA(void)
 {
-    char volume_path[MAX_PATH];
+    char volume_path[MAX_PATH], cwd[MAX_PATH];
     struct {
         const char *file_name;
         const char *path_name;
@@ -671,6 +671,10 @@ static void test_GetVolumePathNameA(void)
             "M::", "C:\\", 4,
             ERROR_FILE_NOT_FOUND, ERROR_MORE_DATA
         },
+        { /* test 17: an unreasonable DOS path */
+            "InvalidDrive:\\AnInvalidFolder", "%CurrentDrive%\\", sizeof(volume_path),
+            NO_ERROR, NO_ERROR
+        },
     };
     BOOL ret, success;
     DWORD error;
@@ -683,6 +687,13 @@ static void test_GetVolumePathNameA(void)
         return;
     }
 
+    /* Obtain the drive of the working directory */
+    ret = GetCurrentDirectoryA( sizeof(cwd), cwd );
+    ok( ret, "Failed to obtain the current working directory.\n" );
+    cwd[2] = 0;
+    ret = SetEnvironmentVariableA( "CurrentDrive", cwd );
+    ok( ret, "Failed to set an environment variable for the current working drive.\n" );
+
     for (i=0; i<sizeof(test_paths)/sizeof(test_paths[0]); i++)
     {
         BOOL broken_ret = test_paths[i].broken_error == NO_ERROR ? TRUE : FALSE;
@@ -699,11 +710,14 @@ static void test_GetVolumePathNameA(void)
 
         if (ret)
         {
+            char path_name[MAX_PATH];
+
+            ExpandEnvironmentStringsA( test_paths[i].path_name, path_name, MAX_PATH);
             /* If we succeeded then make sure the path is correct */
-            success = (strcmp( volume_path, test_paths[i].path_name ) == 0)
-                      || broken(strcasecmp( volume_path, test_paths[i].path_name ) == 0) /* XP */;
+            success = (strcmp( volume_path, path_name ) == 0)
+                      || broken(strcasecmp( volume_path, path_name ) == 0) /* XP */;
             ok(success, "GetVolumePathName test %d unexpectedly returned path %s (expected %s).\n",
-                        i, volume_path, test_paths[i].path_name);
+                        i, volume_path, path_name);
         }
         else
         {
diff --git a/dlls/kernel32/volume.c b/dlls/kernel32/volume.c
index ac6aa48..5e3b148 100644
--- a/dlls/kernel32/volume.c
+++ b/dlls/kernel32/volume.c
@@ -1889,6 +1889,8 @@ BOOL WINAPI GetVolumePathNameW(LPCWSTR filename, LPWSTR volumepathname, DWORD bu
 
     if (status != STATUS_SUCCESS)
     {
+        WCHAR cwdW[MAX_PATH];
+
         /* the path was completely invalid */
         if (filename[0] == '\\')
         {
@@ -1908,6 +1910,16 @@ BOOL WINAPI GetVolumePathNameW(LPCWSTR filename, LPWSTR volumepathname, DWORD bu
                 goto cleanup;
             }
         }
+        else if (GetCurrentDirectoryW( sizeof(cwdW), cwdW ))
+        {
+            /* if the path is completely bogus then revert to the drive of the working directory */
+            fallbackpathW[0] = cwdW[0];
+        }
+        else
+        {
+            status = STATUS_OBJECT_NAME_INVALID;
+            goto cleanup;
+        }
         last_pos = strlenW(fallbackpathW) - 1; /* points to \\ */
         filename = fallbackpathW;
         status = STATUS_SUCCESS;