jdk8u VS mesa

Would an atomic mutable subclass cache (not sure what it's used for, downcasting?) be unnecessary in a language built around static rather than dynamic dispatch by default, like C/C++/Rust and perhaps Go? Or would it still speed up dynamically dispatched code, but is less practical or worthwhile so it isn't used in practice? (Though Rust's Arc also suffers from atomic contention similar to this blog post, when used across dozens of threads: https://pkolaczk.github.io/server-slower-than-a-laptop/)

Also it's somewhat ironic that the JVM source code (https://github.com/openjdk/jdk8u/blob/jdk8u352-b07/hotspot/s...) says "This code is rarely used, so simplicity is a virtue here" at the site of a bottleneck.

Use the latest JDK (Developer's Kit) or JRE (Runtime Environment) for Java 8, compiled and distributed by AdoptOpenJDK from the official Read-Only source.

The majority of the work on 8u, 11u, 17u releases happens in OpenJDK upstream, in so called JDK Updates Projects, by engineers from the interested JDK vendors. You can get a peek who does this kind of work from the repository histories, for example the most recent 11.0.13 is done by engineers from Red Hat (including yours truly), SAP, Azul, Microsoft, BellSoft, Tencent, Amazon, Alibaba, IBM, ARM, Google.

> whatever it returned would just get inserted as a string into the log output, no big deal.

Once you can inject anything that gets resolved, you have an information disclosure vulnerability unrelated to the RCE.

If I can just DNS resolve any ${env} variable from the JVM, a lot of systems are compromised by just exposing the env or system variables configured for runtime.

Just getting your $AWS_ACCESS_KEY_ID and $AWS_SECRET_ACCESS_KEY env vars can compromise your bucket (sure, that is a really unsafe setup now, but it was almost the standard a few years ago over configuring it explicitly).

So a logging system which will merely resolve a hostname derived from a variable was bad enough to compromise many systems.

The serialization loophole was fixed in a jdk8 update.

https://github.com/openjdk/jdk8u/commit/006e84fc77a582552e71...

But even with that in place, the information disclosure of java System or env properties is bad enough to break actual systems in prod.

> Turns out, by including "." in some part of the URL to this remote class, Log4j lets off its guard & simply looks up to that server and dynamically loads the class file.

No it doesn't. That was disabled by default in 2009, and was disabled by default in every release of Java 8 or later: https://github.com/openjdk/jdk8u/commit/006e84fc77a582552e71...

Unless i am mistaken, i don't believe the attack as described by LunaSec actually works against a default-configured JVM released any time in the last decade.

No problems, AMD Adrenalin it's a part of Windows AMD drivers, but on Linux you have not this soft, here is link: https://github.com/Mesa3D/mesa

# apt install libxcb-glx0-dev libx11-xcb-dev libxcb-present-dev libxshmfence-dev libxxf86vm-dev # git clone https://gitlab.freedesktop.org/mesa/mesa # cd mesa meson setup build/ -Dgallium-drivers=lima,panfrost,kmsro,swrast -Dplatforms=x11 -Dvulkan-drivers= -Dllvm=disabled The Meson build system Version: 1.0.1 Source dir: /Dati/mesa Build dir: /Dati/mesa/build Build type: native build Project name: mesa Project version: 23.3.0-devel C compiler for the host machine: cc (gcc 12.2.0 "cc (Debian 12.2.0-14) 12.2.0") C linker for the host machine: cc ld.bfd 2.40 C++ compiler for the host machine: c++ (gcc 12.2.0 "c++ (Debian 12.2.0-14) 12.2.0") C++ linker for the host machine: c++ ld.bfd 2.40 Host machine cpu family: arm Host machine cpu: armv7l Checking if "-mtls-dialect=gnu2" runs: YES Dependency vdpau skipped: feature gallium-vdpau disabled Program glslangValidator found: NO Dependency libva skipped: feature gallium-va disabled Program python3 found: YES (/usr/bin/python3) Fetching value of define "ETIME" : 62 Checking for function "bswap32" : YES Checking for function "bswap64" : YES Checking for function "clz" : YES Checking for function "clzll" : YES Checking for function "ctz" : YES Checking for function "expect" : YES Checking for function "ffs" : YES Checking for function "ffsll" : YES Checking for function "popcount" : YES Checking for function "popcountll" : YES Checking for function "unreachable" : YES Checking for function "types_compatible_p" : YES Compiler for C supports function attribute const: YES Compiler for C supports function attribute flatten: YES Compiler for C supports function attribute malloc: YES Compiler for C supports function attribute pure: YES Compiler for C supports function attribute unused: YES Compiler for C supports function attribute warn_unused_result: YES Compiler for C supports function attribute weak: YES Compiler for C supports function attribute format: YES Compiler for C supports function attribute packed: YES Compiler for C supports function attribute returns_nonnull: YES Compiler for C supports function attribute alias: YES Compiler for C supports function attribute noreturn: YES Compiler for C supports function attribute visibility:hidden: YES Checking if "__uint128_t" compiles: NO Checking for function "reallocarray" : YES Checking for function "fmemopen" : YES Checking if "gc-sections" : links: YES Compiler for C supports arguments -Werror=implicit-function-declaration: YES Compiler for C supports arguments -Werror=missing-prototypes: YES Compiler for C supports arguments -Werror=return-type: YES Compiler for C supports arguments -Werror=empty-body: YES Compiler for C supports arguments -Werror=incompatible-pointer-types: YES Compiler for C supports arguments -Werror=int-conversion: YES Compiler for C supports arguments -Wimplicit-fallthrough: YES Compiler for C supports arguments -Wmisleading-indentation: YES Compiler for C supports arguments -Wno-missing-field-initializers: YES Compiler for C supports arguments -Wno-format-truncation: YES Compiler for C supports arguments -Wno-nonnull-compare: YES Compiler for C supports arguments -fno-math-errno: YES Compiler for C supports arguments -fno-trapping-math: YES Compiler for C supports arguments -Qunused-arguments: NO Compiler for C supports arguments -fno-common: YES Compiler for C supports arguments -Wno-microsoft-enum-value: NO Compiler for C supports arguments -Wno-unused-function: YES Compiler for C supports arguments -Werror=format: YES Compiler for C supports arguments -Wformat-security: YES Compiler for C supports arguments -Werror=thread-safety: NO Compiler for C supports arguments -ffunction-sections: YES Compiler for C supports arguments -fdata-sections: YES Compiler for C++ supports arguments -Werror=return-type: YES Compiler for C++ supports arguments -Werror=empty-body: YES Compiler for C++ supports arguments -Wmisleading-indentation: YES Compiler for C++ supports arguments -Wno-non-virtual-dtor: YES Compiler for C++ supports arguments -Wno-missing-field-initializers: YES Compiler for C++ supports arguments -Wno-format-truncation: YES Compiler for C++ supports arguments -fno-math-errno: YES Compiler for C++ supports arguments -fno-trapping-math: YES Compiler for C++ supports arguments -Qunused-arguments: NO Compiler for C++ supports arguments -flifetime-dse=1: YES Compiler for C++ supports arguments -Wno-microsoft-enum-value: NO Compiler for C++ supports arguments -Werror=format: YES Compiler for C++ supports arguments -Wformat-security: YES Compiler for C++ supports arguments -ffunction-sections: YES Compiler for C++ supports arguments -fdata-sections: YES Compiler for C supports arguments -Wno-override-init: YES Compiler for C supports arguments -Wno-initializer-overrides: NO Compiler for C supports arguments -Werror=pointer-arith: YES Compiler for C supports arguments -Werror=vla: YES Compiler for C supports arguments -Werror=gnu-empty-initializer: NO Compiler for C++ supports arguments -Werror=pointer-arith: YES Compiler for C++ supports arguments -Werror=vla: YES Compiler for C++ supports arguments -Werror=gnu-empty-initializer: NO Checking for function "__builtin_ia32_clflushopt" : NO Checking if "GCC atomic builtins" compiles: YES Checking if "GCC atomic builtins required -latomic" : links: YES Checking if "GCC 64bit atomics" with dependency : links: YES Library ws2_32 found: NO Header "sys/sysmacros.h" has symbol "major" : YES Header "sys/sysmacros.h" has symbol "minor" : YES Header "sys/sysmacros.h" has symbol "makedev" : YES Header "sys/mkdev.h" has symbol "major" : NO Check usable header "sched.h" : YES Checking for function "sched_getaffinity" : YES Check usable header "xlocale.h" : NO Check usable header "linux/futex.h" : YES Check usable header "endian.h" : YES Check usable header "dlfcn.h" : YES Check usable header "sys/shm.h" : YES Check usable header "cet.h" : NO Check usable header "pthread_np.h" : NO Check usable header "renderdoc_app.h" : NO Check usable header "sys/inotify.h" : YES Checking for function "strtof" : YES Checking for function "mkostemp" : YES Checking for function "memfd_create" : YES Checking for function "random_r" : YES Checking for function "flock" : YES Checking for function "strtok_r" : YES Checking for function "getrandom" : YES Checking for function "qsort_s" : NO Checking for function "posix_fallocate" : YES Checking if "GNU qsort_r" : links: YES Header "time.h" has symbol "struct timespec" : YES Checking for function "thrd_create" : YES Header "errno.h" has symbol "program_invocation_name" : YES Header "math.h" has symbol "issignaling" : YES Checking for function "posix_memalign" : YES Checking whether type "struct dirent" has member "d_type" : YES Checking if "strtod has locale support" : links: YES Checking if "Bsymbolic" : links: YES Checking if "version-script" : links: YES Checking if "dynamic-list" : links: YES Compiler for C supports link arguments -Wl,--build-id=sha1: YES Checking for function "dlopen" : YES Checking for function "dladdr" with dependency : YES Checking for function "dl_iterate_phdr" : YES Checking for function "clock_gettime" : YES Found pkg-config: /usr/bin/pkg-config (1.8.1) Run-time dependency zlib found: YES 1.2.13 Run-time dependency libzstd found: YES 1.5.4 Run-time dependency threads found: YES Checking for function "pthread_setaffinity_np" with dependency threads: YES Run-time dependency expat found: YES 2.5.0 Library m found: YES Run-time dependency libdrm found: YES 2.4.114 Run-time dependency libudev found: YES 251 Run-time dependency libelf found: YES 0.188 Run-time dependency valgrind found: NO (tried pkgconfig) Program bison found: YES (/usr/bin/bison) Program bison found: YES 3.8.2 (/usr/bin/bison) Program flex found: YES (/usr/bin/flex) Run-time dependency libunwind found: YES 1.6.2 Run-time dependency x11 found: YES 1.8.4 Run-time dependency xext found: YES 1.3.4 Run-time dependency xfixes found: YES 6.0.0 Run-time dependency xcb-glx found: YES 1.15 Run-time dependency xcb-shm found: YES 1.15 Run-time dependency xcb found: YES 1.15 Found CMake: /usr/bin/cmake (3.25.1) Run-time dependency xcb-keysyms found: NO (tried pkgconfig and cmake) Run-time dependency x11-xcb found: YES 1.8.4 Run-time dependency xcb-dri2 found: YES 1.15 Run-time dependency xcb-dri3 found: YES 1.15 Run-time dependency xcb-present found: YES 1.15 Dependency xcb-shm found: YES 1.15 (cached) Run-time dependency xcb-sync found: YES 1.15 Run-time dependency xshmfence found: YES 1.3 Run-time dependency glproto found: YES 1.4.17 Run-time dependency dri2proto found: YES 2.8 Run-time dependency xxf86vm found: YES 1.1.4 Run-time dependency xcb-xfixes found: YES 1.15 Run-time dependency xcb-randr found: YES 1.15 Run-time dependency xrandr found: YES 1.5.2 Library sensors found: NO Program nm found: YES (/usr/bin/nm) Program symbols-check.py found: YES (/usr/bin/python3 /Dati/mesa/bin/symbols- check.py) Program install_megadrivers.py found: YES (/usr/bin/python3 /Dati/mesa /bin/install_megadrivers.py) Program decode.py found: YES (/Dati/mesa/src/compiler/isaspec/decode.py) Program encode.py found: YES (/Dati/mesa/src/compiler/isaspec/encode.py) Program ln found: YES (/bin/ln) Checking for function "mincore" : YES Build targets in project: 214 mesa 23.3.0-devel Directories prefix : /usr/local libdir : lib/arm-linux-gnueabihf includedir : include Common C and C++ arguments c_cpp_args : -mtls-dialect=gnu2 OpenGL OpenGL : YES ES1 : YES ES2 : YES Shared glapi : YES GLVND : NO DRI Platform : drm Driver dir : /usr/local/lib/arm-linux-gnueabihf/dri GLX Enabled : YES Provider : dri EGL Enabled : YES Drivers : builtin:egl_dri2 builtin:egl_dri3 Platforms : x11 surfaceless drm xcb GBM Enabled : YES Backends path : /usr/local/lib/arm-linux-gnueabihf/gbm Vulkan Drivers : NO Video Codecs : NO APIs : NO LLVM Enabled : NO Gallium Enabled : YES Drivers : lima panfrost kmsro swrast Platforms : x11 surfaceless drm xcb Frontends : mesa Off-screen rendering (OSMesa): NO HUD lm-sensors : NO Perfetto Enabled : NO User defined options gallium-drivers : lima,panfrost,kmsro,swrast llvm : disabled platforms : x11 vulkan-drivers : Found ninja-1.11.1 at /usr/bin/ninja

$ echo "deb-src [signed-by="/usr/share/keyrings/ubuntu-archive-keyring.gpg"] http://ports.ubuntu.com/ubuntu-ports jammy main restricted universe multiverse" >> /etc/apt/sources.list $ sudo apt update $ sudo apt build-dep mesa $ clone https://gitlab.freedesktop.org/mesa/mesa $ cd mesa $ meson build -Dgbm=enabled -Dopengl=true -Degl=enabled -Degl-native-platform=x11 -Dgles1=disabled -Dgles2=enabled -Ddri3=enabled -Dglx=dri -Dllvm=enabled -Dshared-llvm=disabled -Dplatforms=x11,wayland -Dgallium-drivers=swrast,virgl,zink -Dvulkan-drivers=swrast -Dosmesa=true -Dglvnd=true -Dxmlconfig=disabled $ sudo ninja -C build install

Basically there's this one driver for all intel/amd gpus (https://gitlab.freedesktop.org/mesa/mesa) and NVIDIA decided to make their own barely working driver (full of bugs) and also try to make their own standards & protocols instead of using the ones intel/amd have already created

For the curious (I was), I believe this is the associated commit: https://github.com/Mesa3D/mesa/commit/f2e535e4fed5bdc13e11a4...

So you're running Mesa 23 by compiling the code at https://gitlab.freedesktop.org/mesa/mesa/ then?

no it uses amdgpu driver which is build into / part of the kernel (device drivers), and you can use 2 userspace graphics drivers, one being mesa the other one being amdvlk

Good luck, check out https://gitlab.freedesktop.org/mesa/mesa and https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/drivers/gpu/drm?h=v6.2-rc1 this is for Linux, but I don't believe that the size of that project, would be different for windows.