[Bug 12783] Allocation of PEB and TEB can overlap dll mappings

http://bugs.winehq.org/show_bug.cgi?id=12783

--- Comment #8 from Vitaliy Margolen   2008-05-23 13:44:11 ---
(In reply to comment #7)
> The particular case
>     addr = (void *)0x7ffe0000;
>     size = 0x10000;
>     NtAllocateVirtualMemory( NtCurrentProcess(), &addr, 0, &size,
> MEM_RESERVE|MEM_COMMIT, PAGE_READWRITE );
>     user_shared_data = addr;
> probably should have some way to say MAP_FIXED, but I cannot find such a way. 
> [Hint: valgrind presents such a kernel that ignores the first argument to
> mmap() unless MAP_FIXED.]

There is no reason to check for this particular allocation unless to die
immediately if it fails. It's the special data structure [Shared User Data]
present on all NT+ windows at the constant address. If your kernel can not
honor this, then it's broken and have to be fixed. Or listed as incompatible
with Wine. This area is critical to most copy-protection systems. Also lots of
programs make a use of this data structure.