November 2023 - Wine-Devel - list.winehq.org

Re: Handling stack overflow

by Erich E. Hoover

On Thu, Nov 30, 2023 at 2:46 AM Stefan Dösinger <stefandoesinger(a)gmail.com> wrote: > ... > Anti-cheat / Anti-debugger / DRM systems usually don't tell you nicely if they > think something is wrong. When they think you are trying to mess with them > they usually pretend to proceed for a while, do something else and then at a > much later point deliberately crash the process in a weird way. So your > exception handler recursion might be the Anti-cheat's underhanded attempt to > kill the process. I would just like to second that, when I was getting Silverlight working I ran down a number of rabbit holes trying to "fix" things that the DRM was doing wrong on purpose. It's my suspicion that they tested it in some different VMs and found various "failing to fail" ways to detect the presence of the virtualizer. Best, Erich

Nov. 30, 2023

Re: Handling stack overflow

by Stefan Dösinger

Am Montag, 27. November 2023, 06:27:51 EAT schrieb Dāvis Mosāns: > Hi, > > I've been looking to get League of Legends work in Wine. > The issue is that their Anti-Cheat hooks bunch of functions in > ntdll.dll directly by prepending `jmp their_code` before the real > function and it seems it messes something up. > > Anyway, topic of this email is about handling of stack overflow. > When their exception handler gets messed up it is invoked recursively > until stack overflow. > And because it happened while it was in critical section it causes > other threads to deadlock. Since this is anti-cheat it is tricky, and things might not be what they seem. When you say "it messes something up", are you sure the hook is working correctly to begin with? If not, that needs to be fixed rather than handling the fallout exception. Do you know if the recursive invocation happens on Windows too? You mention that the process is killed, so it doesn't sound like it is supposed to happen. Anti-cheat / Anti-debugger / DRM systems usually don't tell you nicely if they think something is wrong. When they think you are trying to mess with them they usually pretend to proceed for a while, do something else and then at a much later point deliberately crash the process in a weird way. So your exception handler recursion might be the Anti-cheat's underhanded attempt to kill the process.

Nov. 30, 2023

Handling stack overflow

by Dāvis Mosāns

Hi, I've been looking to get League of Legends work in Wine. The issue is that their Anti-Cheat hooks bunch of functions in ntdll.dll directly by prepending `jmp their_code` before the real function and it seems it messes something up. Anyway, topic of this email is about handling of stack overflow. When their exception handler gets messed up it is invoked recursively until stack overflow. And because it happened while it was in critical section it causes other threads to deadlock. My question is how such case should be handled? When thread is killed should lock be released so other threads can still proceed? Or maybe just whole process should be killed if any thread has stack overflow? To me it looks like in Windows when exception handler goes too deep then Just in Time debugger is invoked or if that's not enabled then process is killed with EXCEPTION_ACCESS_VIOLATION (maybe because it tried to access beyond end of stack?) Log looks like: [...] 0120:trace:seh:call_handler calling handler 00006FFFFFC97030 (rec=00007F3214C54360, frame=00007F3214D4E710 context=00007F3214C538D0, dispatch=00007F3214C537A0) 0120:trace:seh:call_handler handler at 00006FFFFFC97030 returned 2 0120:trace:seh:call_stack_handlers nested exception 0120:trace:seh:call_handler calling handler 00000001413B347C (rec=00007F3214C54360, frame=00007F3214D4F570 context=00007F3214C538D0, dispatch=00007F3214C537A0) 0120:err:virtual:virtual_setup_exception stack overflow 2576 bytes addr 0x6ffff9e66327 stack 0x7f3214c505f0 (0x7f3214c50000-0x7f3214c51000-0x7f3214d50000) 0124:err:sync:RtlpWaitForCriticalSection section 00006FFFFFCAE4C0 "../wine/dlls/ntdll/loader.c: loader_section" wait timed out in thread 0124, blocked by 0120, retrying (60 sec) 011c:err:sync:RtlpWaitForCriticalSection section 00006FFFFFCAE4C0 "../wine/dlls/ntdll/loader.c: loader_section" wait timed out in thread 011c, blocked by 0120, retrying (60 sec) [...] // stuck like this And several threads stuck like this Thread 8 (Thread 472 "011c"): #0 0x00006fffffc966d4 in NtWaitForAlertByThreadId () from /opt/wine-lol-staging/lib/wine/x86_64-windows/ntdll.dll #1 0x00006fffffc9db68 in RtlWaitOnAddress (addr=addr(a)entry=0x6fffffcae4d8 <loader_section+24>, cmp=cmp(a)entry=0x6fffffcbda90 <zero>, size=size(a)entry=4, timeout=timeout(a)entry=0x7fc37b38f700) at ../wine/dlls/ntdll/sync.c:912 #2 0x00006fffffc9dd06 in wait_semaphore (timeout=<optimized out>, crit=0x6fffffcae4c0 <loader_section>) at ../wine/dlls/ntdll/sync.c:196 #3 RtlpWaitForCriticalSection (crit=crit(a)entry=0x6fffffcae4c0 <loader_section>) at ../wine/dlls/ntdll/sync.c:314 #4 0x00006fffffc9df71 in RtlEnterCriticalSection (crit=crit(a)entry=0x6fffffcae4c0 <loader_section>) at ../wine/dlls/ntdll/sync.c:383 #5 0x00006fffffc7667b in loader_init (context=context(a)entry=0x7fc37b38fb00, entry=entry(a)entry=0x7fc37b38fb80) at ../wine/dlls/ntdll/loader.c:4405 #6 0x00006fffffc9a444 in LdrInitializeThunk (context=0x7fc37b38fb00, unk2=<optimized out>, unk3=<optimized out>, unk4=<optimized out>) at ../wine/dlls/ntdll/signal_x86_64.c:1716 #7 0x00006ffff88f7954 in ?? () from /mnt/Riot Games/League of Legends/wine/dosdevices/s:/Riot Games/League of Legends/Game/stub.dll Best regards, Dāvis

Nov. 27, 2023

Wine staging 8.21 release

by Alistair Leslie-Hughes

Binary packages for various distributions will be available from: https://www.winehq.org/download Summary since last release * Rebased to current wine 8.21 (491 patches are applied to wine vanilla) Upstreamed (Either directly from staging or fixed with a similar patch). * None Added: * None Updated: * vkd3d-latest to latest. Where can you help * Run Steam/Battle.net/GOG/UPlay/Epic * Test your favorite game. * Test your favorite applications. * Improve staging patches and get them accepted upstream. * Suggest patches to be included in staging. As always, if you find a bug, please report it via https://bugs.winehq.org Best Regards Alistair.

Nov. 25, 2023

Re: GCC 4.3 support and language features

by Gerald Pfeifer

On Mon, 13 Nov 2023, Gabriel Ivăncescu wrote: >> The oldest GCC release series I would remotely consider supporting is GCC >> 8 which wend end of life mid 2021, though it's really not unreasonable to >> focus on GCC 11 and later. > Sorry, what? Some distros have 10 year long-term support. Not everything is > rolling release, nor should it be, not even close. I know. In fact I happen to work for one of the Linux distros with the longest, if not the longest, support cycles. > I mean, compiling or backporting compilers isn't that big of a deal but the > main problem with new compilers on old platforms is that you might need new > core libraries (libc, libstdc++, etc) because of how GCC works. We (SUSE in this case, and I believe it similarly holds for Red Hat) do provide newer toolchains for older distros. And we do so in a way that users are fully covered and don't need to build or replace system components on their own. > Having multiple libc side-by-side is difficult, and updating such a core > component in a stable distro is way too much to ask. libc generally isn't affected, though we have been updating it in some cases, and we take care of the default run-time libraries to be suitable for both the older and newer toolschains. (The GNU toolchain puts quite some focus on backwards compatibility of run time components.) Gerald

Nov. 22, 2023

Re: GCC 4.3 support and language features

by Alex Henrie

On Sat, Nov 11, 2023 at 7:34 PM Fabian Maurer <dark.shadow4(a)web.de> wrote: > > Hello wine-devel, > > I wanted to follow up on the discussion on https://gitlab.winehq.org/wine/ > wine/-/merge_requests/3059 > > For those not in the loop: The question came up what GCC version is the oldest > supported one, and which language features can't be used in Wine. Don't forget that it should be possible to compile Wine's PE modules with MSVC too. Microsoft supports each MSVC release for 10 years,[1] and Wine uses designated initializers which MSVC has supported since 2013,[2] so we are currently supporting about the same range of versions as Microsoft does. > Is there already a wiki entry on this? Yes, I rewrote the relevant parts of the wiki after the discussion on merge request !3059, particularly https://wiki.winehq.org/Wine_Developer%27s_Guide/Coding_Practice#Writing_po… It needs to be updated again to document what Alexandre explained today.[3] I'm happy to do that, but it might be a few days before I get to it because my to-do list is _very_ long right now. -Alex [1] https://learn.microsoft.com/en-us/visualstudio/productinfo/vs-servicing [2] https://learn.microsoft.com/en-us/cpp/porting/visual-cpp-what-s-new-2003-th… [3] https://www.winehq.org/mailman3/hyperkitty/list/wine-devel(a)winehq.org/mes…

Nov. 14, 2023

Re: GCC 4.3 support and language features

by Alexandre Julliard

André Zwing <nerv(a)dawncrow.de> writes: > Am 13.11.23 um 16:48 schrieb Francois Gouget: >> On Sun, 12 Nov 2023, Gerald Pfeifer wrote: >> [...] >> >>> On Sun, 12 Nov 2023, Fabian Maurer wrote: >>>> For those not in the loop: The question came up what GCC version is the >>>> oldest supported one, and which language features can't be used in Wine. >>> >>> I recommend we do not cater to versions of GCC that have been end of life >>> for an extended period of time. >> Here are some data points coming from the other side of the >> equation: what gcc versions do Linux distributions ship? >> Then pick the oldest Linux distribution you want to support and that >> tells you which gcc version to support. > > Thanks for the data points. Let me reduce them to the only distributions with long term support for old compilers: > >> Debian 5 gcc 4.3 >> Debian 6 gcc 4.4 >> Debian 7 gcc 4.7.2 >> Debian 8 gcc 4.8.4 >> Debian 9 gcc 6.3.0 >> Debian 10 gcc 8.3.0 >> Debian 11 gcc 10.2.1 >> Debian 12 gcc 12.2.0 > >> RHEL 6.8 gcc 4.4.7 >> RHEL 7.8 gcc 4.8.5 >> RHEL 8.1 gcc 8.3.1 >> RockyLinux 8 gcc 8.5.0 >> AlmaLinux 9 gcc 11.2.1 > > For Debian we shouldn't care about anything before 8. And RHEL 6 has EOL in June 2024. > So IMHO there's no benefit in caring about gcc < 4.8, but 4.8 is worth a discussion. Our policy is to not draw arbitrary lines of supported/unsupported. That's true for C standard versions, compiler versions, distros, window managers, graphics cards, etc. We want to support what our users are actually using. If someone reports an issue with their compiler, we want to look into it. We are not going to reject a report because the compiler is "too old", or out of maintenance, or on a distro we've hever heard of. That doesn't mean we have to fix everything, there's always a trade-off between the complexity/ugliness of the fix, the number of affected users, the availability of a workaround, etc. But that should be decided based on the actual issue, not on some arbitrary version number cutoff. So it may be that we want to require support for typedef redefinitions, because avoiding them is ugly. In practice, that would mean that you can't build with gcc 4.3 out of the box. But it does not mean that gcc 4.3 is somehow "unsupported". If someone reports some other issue with gcc 4.3, and that one is easy to fix, we'll still want to fix it. -- Alexandre Julliard julliard(a)winehq.org

Nov. 14, 2023

Re: GCC 4.3 support and language features

by Fabian Maurer

> For Debian we shouldn't care about anything before 8. And RHEL 6 has EOL in June 2024. > So IMHO there's no benefit in caring about gcc < 4.8, but 4.8 is worth a discussion. Seems sensible to me. IMHO an official decision would be helpful, though. Would it make sense to have configure give an error when your compiler is too old? Regards, Fabian Maurer

Nov. 14, 2023

Re: GCC 4.3 support and language features

by André Zwing

Am 13.11.23 um 16:48 schrieb Francois Gouget: > On Sun, 12 Nov 2023, Gerald Pfeifer wrote: > [...] > >> On Sun, 12 Nov 2023, Fabian Maurer wrote: >>> For those not in the loop: The question came up what GCC version is the >>> oldest supported one, and which language features can't be used in Wine. >> >> I recommend we do not cater to versions of GCC that have been end of life >> for an extended period of time. > > Here are some data points coming from the other side of the > equation: what gcc versions do Linux distributions ship? > > Then pick the oldest Linux distribution you want to support and that > tells you which gcc version to support. Thanks for the data points. Let me reduce them to the only distributions with long term support for old compilers: > Debian 5 gcc 4.3 > Debian 6 gcc 4.4 > Debian 7 gcc 4.7.2 > Debian 8 gcc 4.8.4 > Debian 9 gcc 6.3.0 > Debian 10 gcc 8.3.0 > Debian 11 gcc 10.2.1 > Debian 12 gcc 12.2.0 > RHEL 6.8 gcc 4.4.7 > RHEL 7.8 gcc 4.8.5 > RHEL 8.1 gcc 8.3.1 > RockyLinux 8 gcc 8.5.0 > AlmaLinux 9 gcc 11.2.1 For Debian we shouldn't care about anything before 8. And RHEL 6 has EOL in June 2024. So IMHO there's no benefit in caring about gcc < 4.8, but 4.8 is worth a discussion.

Nov. 13, 2023

Re: GCC 4.3 support and language features

by Francois Gouget

On Sun, 12 Nov 2023, Gerald Pfeifer wrote: [...] > On Sun, 12 Nov 2023, Fabian Maurer wrote: > > For those not in the loop: The question came up what GCC version is the > > oldest supported one, and which language features can't be used in Wine. > > I recommend we do not cater to versions of GCC that have been end of life > for an extended period of time. Here are some data points coming from the other side of the equation: what gcc versions do Linux distributions ship? Then pick the oldest Linux distribution you want to support and that tells you which gcc version to support. Debian 5 gcc 4.3 Debian 6 gcc 4.4 Debian 7 gcc 4.7.2 Debian 8 gcc 4.8.4 Debian 9 gcc 6.3.0 Debian 10 gcc 8.3.0 Debian 11 gcc 10.2.1 Debian 12 gcc 12.2.0 Ubuntu 14.04 LTS gcc 4.8.2 or 4.9-20140406? Ubuntu 16.10 gcc 6.1.1 (I don't have the 16.04 LTS data) Ubuntu 18.04 LTS gcc 8.2.0 Ubuntu 18.10 gcc 8.2.0 Ubuntu 19.04 gcc 8.3.0 Ubuntu 19.10 gcc 9.2.1 Ubuntu 20.04 LTS gcc 9.3.0 or 10-20200411? Ubuntu 20.10 gcc 10.2.0 Ubuntu 21.04 gcc 11.1.0 Ubuntu 21.10 gcc 11.2.0 Ubuntu 22.04 LTS gcc 11.2.0 or 12-20220319? Ubuntu 22.10 gcc 12.2.0 Ubuntu 23.04 gcc 13.1.0 Ubuntu 23.10 gcc 13.2.0 Fedora 31 gcc 9.2.1 Fedora 32 gcc 10.0.1 Fedora 33 gcc 10.2.1 Fedora 34 gcc 11.0.1 Fedora 35 gcc 11.2.1 Fedora 36 gcc 12.1.1 Fedora 37 gcc 12.2.1 Fedora 38 gcc 13.0.1 RHEL 6.8 gcc 4.4.7 RHEL 7.8 gcc 4.8.5 RHEL 8.1 gcc 8.3.1 RockyLinux 8 gcc 8.5.0 AlmaLinux 9 gcc 11.2.1 openSUSE 15.1 gcc 8.2.1 openSUSE 15.2 gcc 9.2.1 openSUSE 15.3 gcc 10.3.0 openSUSE 15.4 gcc 11.3.0 So: * Pick gcc 4.8 for Debian 8 and RHEL 7 support. * Pick gcc 6.3 for Debian 9 support. * Pick gcc 8.2 for most Linux distributions: Debian 10 openSUSE 15.1 RHEL 8 Ubuntu 18.04 LTS -- Francois Gouget <fgouget(a)free.fr> http://fgouget.free.fr/ Hiroshima '45 - Czernobyl '86 - Windows '95

Nov. 13, 2023