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