[Bug 45567] New: League of Legends 8.12+ fails to start a game ( anticheat engine, validation of WoW64 syscall dispatcher)

https://bugs.winehq.org/show_bug.cgi?id=45567

Bug ID: 45567
           Summary: League of Legends 8.12+ fails to start a game
                    (anticheat engine, validation of WoW64 syscall
                    dispatcher)
           Product: Wine
           Version: 3.13
          Hardware: x86
                OS: Linux
            Status: NEW
          Severity: normal
          Priority: P2
         Component: ntdll
          Assignee: [e-mail]
          Reporter: [e-mail]
      Distribution: ---

Diagnosed by Andrew Wesie; partially split off from bug 45327.

The game inspects the %cs register to determine if it is running under WoW64.
Since Linux 32-bit code segment is the same as the
WoW64 32-bit code segment, 0x23, the anti-cheat will expect to be in a WoW64
environment regardless of whether the prefix is 32- or 64-bit.

Consequently the game will try to use the Wow64Transition export if it is
available, or otherwise request the module name of the address contained at the
WOW32Reserved TEB field (i.e. %fs:0xc0), and verifies that the latter matches
wow64cpu.dll.

This can be solved either by moving the syscall dispatcher to wow64cpu.dll, or
by implementing Wow64Transition.