When using dummy-tools STACKPROTECTOR_PER_TASK is unconditionally
selected. This defeats the purpose of the all-enabled tool.
Description copied from arm
Cc: Masahiro Yamada <masahi...@kernel.org>
Signed-off-by: Michal Suchanek <msucha...@suse.de>
---
arch/arm64/Kconfig | 13 ++++++++++++-
1 file changed, 12 insertions(+), 1 deletion(-)
diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig
index a8ff7cd5f096..f59d391e31a4 100644
--- a/arch/arm64/Kconfig
+++ b/arch/arm64/Kconfig
@@ -1549,9 +1549,20 @@ config RANDOMIZE_MODULE_REGION_FULL
config CC_HAVE_STACKPROTECTOR_SYSREG
def_bool $(cc-option,-mstack-protector-guard=sysreg
-mstack-protector-guard-reg=sp_el0 -mstack-protector-guard-offset=0)
+
config STACKPROTECTOR_PER_TASK
- def_bool y
+ bool "Use a unique stack canary value for each task"
depends on STACKPROTECTOR && CC_HAVE_STACKPROTECTOR_SYSREG
+ default y
+ help
+ Due to the fact that GCC uses an ordinary symbol reference from
+ which to load the value of the stack canary, this value can only
+ change at reboot time on SMP systems, and all tasks running in the
+ kernel's address space are forced to use the same canary value for
+ the entire duration that the system is up.
+
+ Enable this option to switch to a different method that uses a
+ different canary value for each task.
endmenu
--
2.26.2
