> On 3 Aug 2022, at 10:59, Peter Müller wrote: > > Hello Michael, > > thanks for your reply. > >> Hello, >> >> I assume that is without any ccache whatsoever? > > Yes, this is without ccache, since I wanted the results to be (somewhat) reproducible. > >> >> Why is this so slow? >> >> From cache, the kernel should build in about 5-ish minutes. > > Indeed. With ccache, the kernel takes about 7 minutes on my workstation. And that is repeatable with the plugin enabled? If so, how is this random? -Michael > Thanks, and best regards, > Peter Müller > >> >> -Michael >> >>> On 2 Aug 2022, at 16:13, Peter Müller wrote: >>> >>> Hello Michael, >>> >>> on my local workstation (featuring an Intel i5-6500), the kernel takes ~ 48 >>> minutes to compile with randstruct enabled, which is around the same time I have >>> experienced before. >>> >>> Thanks, and best regards, >>> Peter Müller >>> >>> >>>> Do we finally know how much the impact is at compile time? >>>> >>>> -Michael >>>> >>>>> On 1 Aug 2022, at 18:18, Peter Müller wrote: >>>>> >>>>> To quote from the kernel documentation: >>>>> >>>>>> If you say Y here, the layouts of structures that are entirely >>>>>> function pointers (and have not been manually annotated with >>>>>> __no_randomize_layout), or structures that have been explicitly >>>>>> marked with __randomize_layout, will be randomized at compile-time. >>>>>> This can introduce the requirement of an additional information >>>>>> exposure vulnerability for exploits targeting these structure >>>>>> types. >>>>>> >>>>>> Enabling this feature will introduce some performance impact, >>>>>> slightly increase memory usage, and prevent the use of forensic >>>>>> tools like Volatility against the system (unless the kernel >>>>>> source tree isn't cleaned after kernel installation). >>>>>> >>>>>> The seed used for compilation is located at >>>>>> scripts/gcc-plgins/randomize_layout_seed.h. It remains after >>>>>> a make clean to allow for external modules to be compiled with >>>>>> the existing seed and will be removed by a make mrproper or >>>>>> make distclean. >>>>>> >>>>>> Note that the implementation requires gcc 4.7 or newer. >>>>> >>>>> Signed-off-by: Peter Müller >>>>> --- >>>>> config/kernel/kernel.config.x86_64-ipfire | 3 ++- >>>>> config/rootfiles/common/aarch64/linux | 5 +++++ >>>>> config/rootfiles/common/armv6l/linux | 5 +++++ >>>>> config/rootfiles/common/x86_64/linux | 5 +++++ >>>>> 4 files changed, 17 insertions(+), 1 deletion(-) >>>>> >>>>> diff --git a/config/kernel/kernel.config.x86_64-ipfire b/config/kernel/kernel.config.x86_64-ipfire >>>>> index 40975b5fc..c8e7ada01 100644 >>>>> --- a/config/kernel/kernel.config.x86_64-ipfire >>>>> +++ b/config/kernel/kernel.config.x86_64-ipfire >>>>> @@ -793,7 +793,8 @@ CONFIG_HAVE_GCC_PLUGINS=y >>>>> CONFIG_GCC_PLUGINS=y >>>>> # CONFIG_GCC_PLUGIN_CYC_COMPLEXITY is not set >>>>> CONFIG_GCC_PLUGIN_LATENT_ENTROPY=y >>>>> -# CONFIG_GCC_PLUGIN_RANDSTRUCT is not set >>>>> +CONFIG_GCC_PLUGIN_RANDSTRUCT=y >>>>> +CONFIG_GCC_PLUGIN_RANDSTRUCT_PERFORMANCE=y >>>>> # end of General architecture-dependent options >>>>> >>>>> CONFIG_RT_MUTEXES=y >>>>> diff --git a/config/rootfiles/common/aarch64/linux b/config/rootfiles/common/aarch64/linux >>>>> index dbd6e8f2f..b3a642e56 100644 >>>>> --- a/config/rootfiles/common/aarch64/linux >>>>> +++ b/config/rootfiles/common/aarch64/linux >>>>> @@ -7646,6 +7646,8 @@ etc/modprobe.d/ipv6.conf >>>>> #lib/modules/KVER-ipfire/build/include/config/GARP >>>>> #lib/modules/KVER-ipfire/build/include/config/GCC_PLUGINS >>>>> #lib/modules/KVER-ipfire/build/include/config/GCC_PLUGIN_LATENT_ENTROPY >>>>> +#lib/modules/KVER-ipfire/build/include/config/GCC_PLUGIN_RANDSTRUCT >>>>> +#lib/modules/KVER-ipfire/build/include/config/GCC_PLUGIN_RANDSTRUCT_PERFORMANCE >>>>> #lib/modules/KVER-ipfire/build/include/config/GCC_PLUGIN_STRUCTLEAK >>>>> #lib/modules/KVER-ipfire/build/include/config/GCC_PLUGIN_STRUCTLEAK_BYREF_ALL >>>>> #lib/modules/KVER-ipfire/build/include/config/GCC_VERSION >>>>> @@ -11684,6 +11686,7 @@ etc/modprobe.d/ipv6.conf >>>>> #lib/modules/KVER-ipfire/build/include/generated/autoconf.h >>>>> #lib/modules/KVER-ipfire/build/include/generated/bounds.h >>>>> #lib/modules/KVER-ipfire/build/include/generated/compile.h >>>>> +#lib/modules/KVER-ipfire/build/include/generated/randomize_layout_hash.h >>>>> #lib/modules/KVER-ipfire/build/include/generated/timeconst.h >>>>> #lib/modules/KVER-ipfire/build/include/generated/uapi >>>>> #lib/modules/KVER-ipfire/build/include/generated/uapi/linux >>>>> @@ -17129,6 +17132,8 @@ etc/modprobe.d/ipv6.conf >>>>> #lib/modules/KVER-ipfire/build/scripts/gcc-plugins/latent_entropy_plugin.c >>>>> #lib/modules/KVER-ipfire/build/scripts/gcc-plugins/latent_entropy_plugin.so >>>>> #lib/modules/KVER-ipfire/build/scripts/gcc-plugins/randomize_layout_plugin.c >>>>> +#lib/modules/KVER-ipfire/build/scripts/gcc-plugins/randomize_layout_plugin.so >>>>> +#lib/modules/KVER-ipfire/build/scripts/gcc-plugins/randomize_layout_seed.h >>>>> #lib/modules/KVER-ipfire/build/scripts/gcc-plugins/sancov_plugin.c >>>>> #lib/modules/KVER-ipfire/build/scripts/gcc-plugins/stackleak_plugin.c >>>>> #lib/modules/KVER-ipfire/build/scripts/gcc-plugins/structleak_plugin.c >>>>> diff --git a/config/rootfiles/common/armv6l/linux b/config/rootfiles/common/armv6l/linux >>>>> index 79e4facfe..c3411fe8d 100644 >>>>> --- a/config/rootfiles/common/armv6l/linux >>>>> +++ b/config/rootfiles/common/armv6l/linux >>>>> @@ -8071,6 +8071,8 @@ etc/modprobe.d/ipv6.conf >>>>> #lib/modules/KVER-ipfire/build/include/config/GCC_PLUGINS >>>>> #lib/modules/KVER-ipfire/build/include/config/GCC_PLUGIN_ARM_SSP_PER_TASK >>>>> #lib/modules/KVER-ipfire/build/include/config/GCC_PLUGIN_LATENT_ENTROPY >>>>> +#lib/modules/KVER-ipfire/build/include/config/GCC_PLUGIN_RANDSTRUCT >>>>> +#lib/modules/KVER-ipfire/build/include/config/GCC_PLUGIN_RANDSTRUCT_PERFORMANCE >>>>> #lib/modules/KVER-ipfire/build/include/config/GCC_PLUGIN_STRUCTLEAK >>>>> #lib/modules/KVER-ipfire/build/include/config/GCC_PLUGIN_STRUCTLEAK_BYREF_ALL >>>>> #lib/modules/KVER-ipfire/build/include/config/GCC_VERSION >>>>> @@ -12134,6 +12136,7 @@ etc/modprobe.d/ipv6.conf >>>>> #lib/modules/KVER-ipfire/build/include/generated/autoconf.h >>>>> #lib/modules/KVER-ipfire/build/include/generated/bounds.h >>>>> #lib/modules/KVER-ipfire/build/include/generated/compile.h >>>>> +#lib/modules/KVER-ipfire/build/include/generated/randomize_layout_hash.h >>>>> #lib/modules/KVER-ipfire/build/include/generated/timeconst.h >>>>> #lib/modules/KVER-ipfire/build/include/generated/uapi >>>>> #lib/modules/KVER-ipfire/build/include/generated/uapi/linux >>>>> @@ -17579,6 +17582,8 @@ etc/modprobe.d/ipv6.conf >>>>> #lib/modules/KVER-ipfire/build/scripts/gcc-plugins/latent_entropy_plugin.c >>>>> #lib/modules/KVER-ipfire/build/scripts/gcc-plugins/latent_entropy_plugin.so >>>>> #lib/modules/KVER-ipfire/build/scripts/gcc-plugins/randomize_layout_plugin.c >>>>> +#lib/modules/KVER-ipfire/build/scripts/gcc-plugins/randomize_layout_plugin.so >>>>> +#lib/modules/KVER-ipfire/build/scripts/gcc-plugins/randomize_layout_seed.h >>>>> #lib/modules/KVER-ipfire/build/scripts/gcc-plugins/sancov_plugin.c >>>>> #lib/modules/KVER-ipfire/build/scripts/gcc-plugins/stackleak_plugin.c >>>>> #lib/modules/KVER-ipfire/build/scripts/gcc-plugins/structleak_plugin.c >>>>> diff --git a/config/rootfiles/common/x86_64/linux b/config/rootfiles/common/x86_64/linux >>>>> index b25f85a3a..1b78fe8c5 100644 >>>>> --- a/config/rootfiles/common/x86_64/linux >>>>> +++ b/config/rootfiles/common/x86_64/linux >>>>> @@ -7624,6 +7624,8 @@ etc/modprobe.d/ipv6.conf >>>>> #lib/modules/KVER-ipfire/build/include/config/GARP >>>>> #lib/modules/KVER-ipfire/build/include/config/GCC_PLUGINS >>>>> #lib/modules/KVER-ipfire/build/include/config/GCC_PLUGIN_LATENT_ENTROPY >>>>> +#lib/modules/KVER-ipfire/build/include/config/GCC_PLUGIN_RANDSTRUCT >>>>> +#lib/modules/KVER-ipfire/build/include/config/GCC_PLUGIN_RANDSTRUCT_PERFORMANCE >>>>> #lib/modules/KVER-ipfire/build/include/config/GCC_PLUGIN_STRUCTLEAK >>>>> #lib/modules/KVER-ipfire/build/include/config/GCC_PLUGIN_STRUCTLEAK_BYREF_ALL >>>>> #lib/modules/KVER-ipfire/build/include/config/GCC_VERSION >>>>> @@ -12128,6 +12130,7 @@ etc/modprobe.d/ipv6.conf >>>>> #lib/modules/KVER-ipfire/build/include/generated/autoconf.h >>>>> #lib/modules/KVER-ipfire/build/include/generated/bounds.h >>>>> #lib/modules/KVER-ipfire/build/include/generated/compile.h >>>>> +#lib/modules/KVER-ipfire/build/include/generated/randomize_layout_hash.h >>>>> #lib/modules/KVER-ipfire/build/include/generated/timeconst.h >>>>> #lib/modules/KVER-ipfire/build/include/generated/uapi >>>>> #lib/modules/KVER-ipfire/build/include/generated/uapi/linux >>>>> @@ -17567,6 +17570,8 @@ etc/modprobe.d/ipv6.conf >>>>> #lib/modules/KVER-ipfire/build/scripts/gcc-plugins/latent_entropy_plugin.c >>>>> #lib/modules/KVER-ipfire/build/scripts/gcc-plugins/latent_entropy_plugin.so >>>>> #lib/modules/KVER-ipfire/build/scripts/gcc-plugins/randomize_layout_plugin.c >>>>> +#lib/modules/KVER-ipfire/build/scripts/gcc-plugins/randomize_layout_plugin.so >>>>> +#lib/modules/KVER-ipfire/build/scripts/gcc-plugins/randomize_layout_seed.h >>>>> #lib/modules/KVER-ipfire/build/scripts/gcc-plugins/sancov_plugin.c >>>>> #lib/modules/KVER-ipfire/build/scripts/gcc-plugins/stackleak_plugin.c >>>>> #lib/modules/KVER-ipfire/build/scripts/gcc-plugins/structleak_plugin.c >>>>> -- >>>>> 2.35.3 >>>> >>