[PATCH] winsup/cygwin: Protect fork() against dll- and exe-updates.

cyg Simple cygsimple@gmail.com
Fri Aug 7 16:37:00 GMT 2015

On 8/7/2015 12:18 PM, Corinna Vinschen wrote:
> On Aug  7 11:01, cyg Simple wrote:
>> On 8/3/2015 4:21 PM, Corinna Vinschen wrote:
>>> The HMODULE is only the address of the section so, no, there's no way to
>>> do an NtCreateFile with this information alone.  As for the file id, I
>>> never tried NtOpenFile w/ FILE_OPEN_BY_FILE_ID.  The usage description
>>> in the WDK docs is a bit vague, but it does work.  You just have to have
>>> the file id from some earlier call to NtQueryInformationFile.
>> I seem to remember that the file id isn't guaranteed to be constant on
>> Windows FS, especially FAT, unless you keep the file open.
> FAT doesn't support opening files by file ID.  On NTFS, file IDs are
> constant and unique per file as long as it exists.  Se the remarks
> secion in
> https://msdn.microsoft.com/en-us/library/windows/desktop/aa363788%28v=vs.85%29.aspx

Okay good.  The first paragraph was what I was remembering.

But ReplaceFile could use the same ID on the replacement file; that
could cause issues if you expect the name to be the same.

cyg Simple

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