Re: [Qemu-devel] [PATCH] qga-win: fall back to hardcoded user and group names if LookupAccountSidW failed

[Michael Roth]

Quoting Chen Hanxiao (2017-10-26 04:27:40)
> 
> 
> At 2017-10-26 05:58:07, "Michael Roth" <address@hidden> wrote:
> >Quoting Tomáš Golembiovský (2017-09-29 16:31:02)
> >> On Fri, 29 Sep 2017 17:11:22 +0800
> >> Chen Hanxiao <address@hidden> wrote:
> >> 
> >> > From: Chen Hanxiao <address@hidden>
> >> > 
> >> > On some of windows (win08 sp2),
> >> > it doesn't work by calling LookupAccountSidW with
> >> > well-known SIDs,
> >> > We got an error:
> >> >     error 997 overlapped I/O operation is in progress
> >> > 
> >> > But hardcoded names work.
> >> > 
> >> > This patch introduces a workaroud for this issue:
> >> > if LookupAccountSidW failed, try hardcoded one.
> >> > 
> >> > Signed-off-by: Chen Hanxiao <address@hidden>
> >> > ---
> >> >  qga/vss-win32/install.cpp | 10 ++++++++--
> >> >  1 file changed, 8 insertions(+), 2 deletions(-)
> >> > 
> >> 
> >> I wonder if it's caused by qga itself or a race/conflict with some other
> >> app. But still...
> >> 
> >> 
> >> Reviewed-by: Tomáš Golembiovský <address@hidden>
> >
> >I think it might be getNameByStringSID()/LookupAccountSidW() reporting a
> >stale GetLastError() value.
> >
> >Does this fix the issue?
> 
> Not exactly.
> I tested your patch several times, it improved greatly.
> But failed only one time,
> got another error 1722.

Hmm, was that error also from the getNameByStringSID() call?

> 
> Build with my fallback patch and your suggestion, 
> installation work perfectly.

Thanks for testing.

> 
> Regards,
> - Chen
> 
> >
> >diff --git a/qga/vss-win32/install.cpp b/qga/vss-win32/install.cpp
> >index ba7c94eb25..94c921e8de 100644
> >--- a/qga/vss-win32/install.cpp
> >+++ b/qga/vss-win32/install.cpp
> >@@ -149,9 +149,10 @@ static HRESULT getNameByStringSID(
> >     wchar_t domainName[BUFFER_SIZE];
> > 
> >     chk(ConvertStringSidToSidW(sid, &psid));
> >-    LookupAccountSidW(NULL, psid, buffer, bufferLen,
> >-                domainName, &domainNameLen, &groupType);
> >-    hr = HRESULT_FROM_WIN32(GetLastError());
> >+    if (!LookupAccountSidW(NULL, psid, buffer, bufferLen,
> >+                           domainName, &domainNameLen, &groupType)) {
> >+        hr = HRESULT_FROM_WIN32(GetLastError());
> >+    }
> > 
> >     LocalFree(psid);
> >
> >> 
> >> 
> >> -- 
> >> Tomáš Golembiovský <address@hidden>
> >> 
> >