[PATCH v3 2/3] fix: passing wrong roots for get_mountmgr_drive_type

[robert]

From: robert

---
 dlls/kernelbase/volume.c | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/dlls/kernelbase/volume.c b/dlls/kernelbase/volume.c
index 1ee93d1e6b1..3759a60dfa8 100644
--- a/dlls/kernelbase/volume.c
+++ b/dlls/kernelbase/volume.c
@@ -127,7 +127,11 @@ static DWORD get_mountmgr_drive_type( LPCWSTR root )
     DWORD br;

memset( &data, 0, sizeof(data) );
-    if (root) data.letter = root[0];
+    if (root)
+    {
+        if (strlen(root) < 3 || root[1] != ':' || root[2] != '\') return DRIVE_UNKNOWN;
+        data.letter = root[0];
+    }
     else
     {
         WCHAR curdir[MAX_PATH];