From: "Peter Müller" <peter.mueller@ipfire.org>
To: development@lists.ipfire.org
Subject: [PATCH] linux: Randomize layout of sensitive kernel structures
Date: Mon, 01 Aug 2022 17:18:07 +0000 [thread overview]
Message-ID: <6f293556-db9a-086e-1b2d-5e7d10eee48b@ipfire.org> (raw)
[-- Attachment #1: Type: text/plain, Size: 7852 bytes --]
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 <peter.mueller(a)ipfire.org>
---
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
next reply other threads:[~2022-08-01 17:18 UTC|newest]
Thread overview: 7+ messages / expand[flat|nested] mbox.gz Atom feed top
2022-08-01 17:18 Peter Müller [this message]
2022-08-01 20:18 ` Michael Tremer
2022-08-02 15:13 ` Peter Müller
2022-08-03 8:30 ` Michael Tremer
2022-08-03 9:59 ` Peter Müller
2022-08-03 10:28 ` Michael Tremer
2022-08-03 10:51 ` Michael Tremer
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