Tim Clem : kernelbase: Don't assume the length of the process image name.

[Alexandre Julliard]

Module: wine
Branch: master
Commit: a7937e83b2f8606aa777098eb5e738241a5458e1
URL:    https://gitlab.winehq.org/wine/wine/-/commit/a7937e83b2f8606aa777098eb5e738241a5458e1

Author: Tim Clem <tclem at codeweavers.com>
Date:   Tue Aug  9 13:10:15 2022 -0700

kernelbase: Don't assume the length of the process image name.

NtQueryInformationProcess(ProcessImageFileNameWin32) may return an
empty string in some circumstances, which leads
QueryFullProcessImageNameW to crash if called with flags including
PROCESS_NAME_NATIVE, as that path assumed the image name had a length
of at least 2.

---

 dlls/kernelbase/debug.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/dlls/kernelbase/debug.c b/dlls/kernelbase/debug.c
index 9e954e3ffbe..cd8e0d7f87d 100644
--- a/dlls/kernelbase/debug.c
+++ b/dlls/kernelbase/debug.c
@@ -1575,7 +1575,7 @@ BOOL WINAPI DECLSPEC_HOTPATCH QueryFullProcessImageNameW( HANDLE process, DWORD
 
     if (status) goto cleanup;
 
-    if (flags & PROCESS_NAME_NATIVE)
+    if (flags & PROCESS_NAME_NATIVE && result->Length > 2 * sizeof(WCHAR))
     {
         WCHAR drive[3];
         WCHAR device[1024];