Thomas Faber : dbghelp: Accept NULL search path in SymSetSearchPath.

[Alexandre Julliard]

Module: wine
Branch: master
Commit: 06f1c40f17ad09aa7ab72f44c705be78dcf6daf3
URL:    https://source.winehq.org/git/wine.git/?a=commit;h=06f1c40f17ad09aa7ab72f44c705be78dcf6daf3

Author: Thomas Faber <thomas.faber at reactos.org>
Date:   Fri Nov 12 18:11:48 2021 -0500

dbghelp: Accept NULL search path in SymSetSearchPath.

Fixes a crash when starting kernrate.exe.

Signed-off-by: Thomas Faber <thomas.faber at reactos.org>
Signed-off-by: Alexandre Julliard <julliard at winehq.org>

---

 dlls/dbghelp/dbghelp.c | 87 +++++++++++++++++++++++++++++++-------------------
 1 file changed, 54 insertions(+), 33 deletions(-)

diff --git a/dlls/dbghelp/dbghelp.c b/dlls/dbghelp/dbghelp.c
index c0b8837fbbf..428ea10e2d3 100644
--- a/dlls/dbghelp/dbghelp.c
+++ b/dlls/dbghelp/dbghelp.c
@@ -175,6 +175,36 @@ struct cpu* cpu_find(DWORD machine)
     return NULL;
 }
 
+static WCHAR* make_default_search_path(void)
+{
+    WCHAR*      search_path;
+    unsigned    size;
+    unsigned    len;
+
+    search_path = HeapAlloc(GetProcessHeap(), 0, (len = MAX_PATH) * sizeof(WCHAR));
+    while ((size = GetCurrentDirectoryW(len, search_path)) >= len)
+        search_path = HeapReAlloc(GetProcessHeap(), 0, search_path, (len *= 2) * sizeof(WCHAR));
+    search_path = HeapReAlloc(GetProcessHeap(), 0, search_path, (size + 1) * sizeof(WCHAR));
+
+    len = GetEnvironmentVariableW(L"_NT_SYMBOL_PATH", NULL, 0);
+    if (len)
+    {
+        search_path = HeapReAlloc(GetProcessHeap(), 0, search_path, (size + 1 + len + 1) * sizeof(WCHAR));
+        search_path[size] = ';';
+        GetEnvironmentVariableW(L"_NT_SYMBOL_PATH", search_path + size + 1, len);
+        size += 1 + len;
+    }
+    len = GetEnvironmentVariableW(L"_NT_ALTERNATE_SYMBOL_PATH", NULL, 0);
+    if (len)
+    {
+        search_path = HeapReAlloc(GetProcessHeap(), 0, search_path, (size + 1 + len + 1) * sizeof(WCHAR));
+        search_path[size] = ';';
+        GetEnvironmentVariableW(L"_NT_ALTERNATE_SYMBOL_PATH", search_path + size + 1, len);
+    }
+
+    return search_path;
+}
+
 /******************************************************************
  *		SymSetSearchPathW (DBGHELP.@)
  *
@@ -182,14 +212,24 @@ struct cpu* cpu_find(DWORD machine)
 BOOL WINAPI SymSetSearchPathW(HANDLE hProcess, PCWSTR searchPath)
 {
     struct process* pcs = process_find_by_handle(hProcess);
+    WCHAR*          search_path_buffer;
 
     if (!pcs) return FALSE;
-    if (!searchPath) return FALSE;
 
+    if (searchPath)
+    {
+        search_path_buffer = HeapAlloc(GetProcessHeap(), 0,
+                                       (lstrlenW(searchPath) + 1) * sizeof(WCHAR));
+        if (!search_path_buffer) return FALSE;
+        lstrcpyW(search_path_buffer, searchPath);
+    }
+    else
+    {
+        search_path_buffer = make_default_search_path();
+        if (!search_path_buffer) return FALSE;
+    }
     HeapFree(GetProcessHeap(), 0, pcs->search_path);
-    pcs->search_path = lstrcpyW(HeapAlloc(GetProcessHeap(), 0, 
-                                          (lstrlenW(searchPath) + 1) * sizeof(WCHAR)),
-                                searchPath);
+    pcs->search_path = search_path_buffer;
     return TRUE;
 }
 
@@ -201,16 +241,19 @@ BOOL WINAPI SymSetSearchPath(HANDLE hProcess, PCSTR searchPath)
 {
     BOOL        ret = FALSE;
     unsigned    len;
-    WCHAR*      sp;
+    WCHAR*      sp = NULL;
 
-    len = MultiByteToWideChar(CP_ACP, 0, searchPath, -1, NULL, 0);
-    if ((sp = HeapAlloc(GetProcessHeap(), 0, len * sizeof(WCHAR))))
+    if (searchPath)
     {
+        len = MultiByteToWideChar(CP_ACP, 0, searchPath, -1, NULL, 0);
+        sp = HeapAlloc(GetProcessHeap(), 0, len * sizeof(WCHAR));
+        if (!sp) return FALSE;
         MultiByteToWideChar(CP_ACP, 0, searchPath, -1, sp, len);
-
-        ret = SymSetSearchPathW(hProcess, sp);
-        HeapFree(GetProcessHeap(), 0, sp);
     }
+
+    ret = SymSetSearchPathW(hProcess, sp);
+
+    HeapFree(GetProcessHeap(), 0, sp);
     return ret;
 }
 
@@ -428,29 +471,7 @@ BOOL WINAPI SymInitializeW(HANDLE hProcess, PCWSTR UserSearchPath, BOOL fInvadeP
     }
     else
     {
-        unsigned        size;
-        unsigned        len;
-
-        pcs->search_path = HeapAlloc(GetProcessHeap(), 0, (len = MAX_PATH) * sizeof(WCHAR));
-        while ((size = GetCurrentDirectoryW(len, pcs->search_path)) >= len)
-            pcs->search_path = HeapReAlloc(GetProcessHeap(), 0, pcs->search_path, (len *= 2) * sizeof(WCHAR));
-        pcs->search_path = HeapReAlloc(GetProcessHeap(), 0, pcs->search_path, (size + 1) * sizeof(WCHAR));
-
-        len = GetEnvironmentVariableW(L"_NT_SYMBOL_PATH", NULL, 0);
-        if (len)
-        {
-            pcs->search_path = HeapReAlloc(GetProcessHeap(), 0, pcs->search_path, (size + 1 + len + 1) * sizeof(WCHAR));
-            pcs->search_path[size] = ';';
-            GetEnvironmentVariableW(L"_NT_SYMBOL_PATH", pcs->search_path + size + 1, len);
-            size += 1 + len;
-        }
-        len = GetEnvironmentVariableW(L"_NT_ALTERNATE_SYMBOL_PATH", NULL, 0);
-        if (len)
-        {
-            pcs->search_path = HeapReAlloc(GetProcessHeap(), 0, pcs->search_path, (size + 1 + len + 1) * sizeof(WCHAR));
-            pcs->search_path[size] = ';';
-            GetEnvironmentVariableW(L"_NT_ALTERNATE_SYMBOL_PATH", pcs->search_path + size + 1, len);
-        }
+        pcs->search_path = make_default_search_path();
     }
 
     pcs->lmodules = NULL;