[PATCH 0/2] MR6004: comctl32: A NULL string fix.

[PATCH 1/2] comctl32: Fail on NULL string for edit control WM_GETTEXT message.

[Aida Jonikienė]

From: Aida Jonikienė

Zadig passes a fixed string length to WM_GETTEXT in one place regardless of the string:
https://github.com/pbatard/libwdi/blob/9b23b82a2dd1cbffc16d46c212f92c6bf8c0c...
(which causes a segfault with NULL strings on Wine but not on Windows).

This fixes an unrelated issue in https://bugs.winehq.org/show_bug.cgi?id=54750
(but not the main one).
---
 dlls/comctl32/edit.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/dlls/comctl32/edit.c b/dlls/comctl32/edit.c
index 4b950412617..b7fd50a75e9 100644
--- a/dlls/comctl32/edit.c
+++ b/dlls/comctl32/edit.c
@@ -3183,7 +3183,7 @@ static void EDIT_WM_ContextMenu(EDITSTATE *es, INT x, INT y)
  */
 static INT EDIT_WM_GetText(const EDITSTATE *es, INT count, LPWSTR dst)
 {
-    if (!count)
+    if (!count || !dst)
         return 0;

lstrcpynW(dst, es->text, count);

[PATCH 2/2] comctl32/tests: Add tests for NULL strings in edit control WM_GETTEXT message.

[Aida Jonikienė]

From: Aida Jonikienė

These pass on Windows: https://testbot.winehq.org/JobDetails.pl?Key=146845
---
 dlls/comctl32/tests/edit.c | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/dlls/comctl32/tests/edit.c b/dlls/comctl32/tests/edit.c
index bce0215ef19..12900667f01 100644
--- a/dlls/comctl32/tests/edit.c
+++ b/dlls/comctl32/tests/edit.c
@@ -1470,6 +1470,11 @@ static void test_edit_control_6(void)
     ok(ret == strlen(str), "Expected %s, got len %ld\n", str, ret);
     ok(!strcmp(buf, str), "Expected %s, got %s\n", str, buf);

+    ret = SendMessageA(hWnd, WM_GETTEXT, MAXLEN, (LPARAM)NULL);
+    ok(ret == 0, "Expected 0, got len %ld\n", ret);
+    ret = SendMessageA(hWnd, WM_GETTEXT, 0, (LPARAM)NULL);
+    ok(ret == 0, "Expected 0, got len %ld\n", ret);
+
     buf[0] = 0;
     ret = SendMessageA(hWnd, WM_DESTROY, 0, 0);
     todo_wine