[reactos] 01/01: [SHELL32] RegFolder must correctly handle GetDisplayNameOf parsing paths (#6265)

[Whindmar Saksit]

https://git.reactos.org/?p=reactos.git;a=commitdiff;h=55a5d7a177b9fc38a506f…

commit 55a5d7a177b9fc38a506f8fa57a82870321ca8d9
Author:     Whindmar Saksit <whindsaks(a)proton.me>
AuthorDate: Mon Jan 8 17:02:59 2024 +0100
Commit:     GitHub <noreply(a)github.com>
CommitDate: Mon Jan 8 17:02:59 2024 +0100

    [SHELL32] RegFolder must correctly handle GetDisplayNameOf parsing paths (#6265)
---
 dll/win32/shell32/folders/CRegFolder.cpp | 40 +++++++++++++++++++++++++-------
 1 file changed, 32 insertions(+), 8 deletions(-)

diff --git a/dll/win32/shell32/folders/CRegFolder.cpp
b/dll/win32/shell32/folders/CRegFolder.cpp
index 16b0b7325e2..5b2d513569b 100644
--- a/dll/win32/shell32/folders/CRegFolder.cpp
+++ b/dll/win32/shell32/folders/CRegFolder.cpp
@@ -641,7 +641,8 @@ HRESULT WINAPI CRegFolder::GetDisplayNameOf(PCUITEMID_CHILD pidl,
DWORD dwFlags,
     }
 
     /* Allocate the buffer for the result */
-    LPWSTR pszPath = (LPWSTR)CoTaskMemAlloc((MAX_PATH + 1) * sizeof(WCHAR));
+    SIZE_T cchPath = MAX_PATH + 1;
+    LPWSTR pszPath = (LPWSTR)CoTaskMemAlloc(cchPath * sizeof(WCHAR));
     if (!pszPath)
         return E_OUTOFMEMORY;
 
@@ -649,18 +650,41 @@ HRESULT WINAPI CRegFolder::GetDisplayNameOf(PCUITEMID_CHILD pidl,
DWORD dwFlags,
 
     if (GET_SHGDN_FOR (dwFlags) == SHGDN_FORPARSING)
     {
-        wcscpy(pszPath, m_rootPath);
-        PWCHAR pItemName = &pszPath[wcslen(pszPath)];
+        SIZE_T pathlen = 0;
+        PWCHAR pItemName = pszPath; // GET_SHGDN_RELATION(dwFlags) == SHGDN_INFOLDER
+        if (GET_SHGDN_RELATION(dwFlags) != SHGDN_INFOLDER)
+        {
+            hr = StringCchCopyW(pszPath, cchPath, m_rootPath);
+            if (SUCCEEDED(hr))
+            {
+                pathlen = wcslen(pszPath);
+                pItemName = &pszPath[pathlen];
+                if (pathlen)
+                {
+                    if (++pathlen < cchPath)
+                        *pItemName++ = L'\\';
+                    else
+                        hr = HRESULT_FROM_WIN32(ERROR_INSUFFICIENT_BUFFER);
+                }
+            }
+        }
 
-        /* parsing name like ::{...} */
-        pItemName[0] = ':';
-        pItemName[1] = ':';
-        SHELL32_GUIDToStringW (*clsid, &pItemName[2]);
+        if (SUCCEEDED(hr) && pathlen + 2 + 38 + 1 < cchPath)
+        {
+            /* parsing name like ::{...} */
+            pItemName[0] = L':';
+            pItemName[1] = L':';
+            SHELL32_GUIDToStringW(*clsid, &pItemName[2]);
+        }
+        else
+        {
+            hr = HRESULT_FROM_WIN32(ERROR_INSUFFICIENT_BUFFER);
+        }
     }
     else
     {
         /* user friendly name */
-        if (!HCR_GetClassNameW (*clsid, pszPath, MAX_PATH))
+        if (!HCR_GetClassNameW(*clsid, pszPath, cchPath))
             hr = E_FAIL;
     }