CYGWIN's fork() function is broken in ReactOS

Easy to reproduce: using cmd execute forked.exe from forked.zip with cygwin1.dll in the same folder.

Expected result: forked.exe uses fork() to create a child process, then you should see an output like this:

fork() returns 2888

fork() returns 0

This works in Windows XP SP3

Current behavior in ReactOS: forked.exe shows the following output:

fork() returns -1

A -1 return value means the function failed somewhere, plus, a zombie forked.exe process is created waiting for 5 minutes before terminating by itself.

This is the most relevant part in debug log:

(/ntoskrnl/mm/ARM3/virtual.c:5336) Unable to find VAD for address 0x60FF0000

(/ntoskrnl/se/accesschk.c:541) Request for zero access to an object. Denying.

(/ntoskrnl/mm/ARM3/virtual.c:5336) Unable to find VAD for address 0x60FC0000

(/ntoskrnl/mm/ARM3/virtual.c:5336) Unable to find VAD for address 0x60FF0000

(/ntoskrnl/mm/ARM3/virtual.c:5336) Unable to find VAD for address 0x60FE0000

(/ntoskrnl/mm/ARM3/virtual.c:5336) Unable to find VAD for address 0x60FD0000

Tested in both bootcd and livecd.

Aside note: this is fixed by Cygwin 2.5.2, but because another bug, it only works in bootcd builds, but for this report, I want to focus in Cygwin 1.7.18.

PD: Please apologize me for editing many times this bug report.