summaryrefslogtreecommitdiff
path: root/scripts/gcc-plugins/Kconfig
diff options
context:
space:
mode:
Diffstat (limited to 'scripts/gcc-plugins/Kconfig')
-rw-r--r--scripts/gcc-plugins/Kconfig51
1 files changed, 51 insertions, 0 deletions
diff --git a/scripts/gcc-plugins/Kconfig b/scripts/gcc-plugins/Kconfig
index cb0c889e13aa..0d5c799688f0 100644
--- a/scripts/gcc-plugins/Kconfig
+++ b/scripts/gcc-plugins/Kconfig
@@ -139,4 +139,55 @@ config GCC_PLUGIN_RANDSTRUCT_PERFORMANCE
in structures. This reduces the performance hit of RANDSTRUCT
at the cost of weakened randomization.
+config GCC_PLUGIN_STACKLEAK
+ bool "Erase the kernel stack before returning from syscalls"
+ depends on GCC_PLUGINS
+ depends on HAVE_ARCH_STACKLEAK
+ help
+ This option makes the kernel erase the kernel stack before
+ returning from system calls. That reduces the information which
+ kernel stack leak bugs can reveal and blocks some uninitialized
+ stack variable attacks.
+
+ The tradeoff is the performance impact: on a single CPU system kernel
+ compilation sees a 1% slowdown, other systems and workloads may vary
+ and you are advised to test this feature on your expected workload
+ before deploying it.
+
+ This plugin was ported from grsecurity/PaX. More information at:
+ * https://grsecurity.net/
+ * https://pax.grsecurity.net/
+
+config STACKLEAK_TRACK_MIN_SIZE
+ int "Minimum stack frame size of functions tracked by STACKLEAK"
+ default 100
+ range 0 4096
+ depends on GCC_PLUGIN_STACKLEAK
+ help
+ The STACKLEAK gcc plugin instruments the kernel code for tracking
+ the lowest border of the kernel stack (and for some other purposes).
+ It inserts the stackleak_track_stack() call for the functions with
+ a stack frame size greater than or equal to this parameter.
+ If unsure, leave the default value 100.
+
+config STACKLEAK_METRICS
+ bool "Show STACKLEAK metrics in the /proc file system"
+ depends on GCC_PLUGIN_STACKLEAK
+ depends on PROC_FS
+ help
+ If this is set, STACKLEAK metrics for every task are available in
+ the /proc file system. In particular, /proc/<pid>/stack_depth
+ shows the maximum kernel stack consumption for the current and
+ previous syscalls. Although this information is not precise, it
+ can be useful for estimating the STACKLEAK performance impact for
+ your workloads.
+
+config STACKLEAK_RUNTIME_DISABLE
+ bool "Allow runtime disabling of kernel stack erasing"
+ depends on GCC_PLUGIN_STACKLEAK
+ help
+ This option provides 'stack_erasing' sysctl, which can be used in
+ runtime to control kernel stack erasing for kernels built with
+ CONFIG_GCC_PLUGIN_STACKLEAK.
+
endif