Enable previously added CONFIG_STACK_PROTECTOR feature for ARM
platform. We initialize stack protector in two stages: from head.S
using boot_stack_chk_guard_setup_early() function and from start_xen()
using boot_stack_chk_guard_setup(). This ensures that all C code from
the very beginning can use stack protector.
We call boot_stack_chk_guard_setup() only after time subsystem was
initialized to make sure that generic random number generator will
be working properly.
Signed-off-by: Volodymyr Babchuk <volodymyr_babchuk@epam.com>
---
In v3:
- Call boot_stack_chk_guard_setup_early from head.S to ensure
that stack is protected from early boot stages
- Call boot_stack_chk_guard_setup() later, when time subsystem is
sufficiently initialized to provide values for the random number
generator.
In v2:
- Reordered Kconfig entry
---
xen/arch/arm/Kconfig | 1 +
xen/arch/arm/arm64/head.S | 3 +++
xen/arch/arm/setup.c | 3 +++
3 files changed, 7 insertions(+)
diff --git a/xen/arch/arm/Kconfig b/xen/arch/arm/Kconfig
index 23bbc91aad..a24c88c327 100644
--- a/xen/arch/arm/Kconfig
+++ b/xen/arch/arm/Kconfig
@@ -16,6 +16,7 @@ config ARM
select HAS_ALTERNATIVE if HAS_VMAP
select HAS_DEVICE_TREE
select HAS_PASSTHROUGH
+ select HAS_STACK_PROTECTOR
select HAS_UBSAN
select IOMMU_FORCE_PT_SHARE
diff --git a/xen/arch/arm/arm64/head.S b/xen/arch/arm/arm64/head.S
index 72c7b24498..535969e9c0 100644
--- a/xen/arch/arm/arm64/head.S
+++ b/xen/arch/arm/arm64/head.S
@@ -250,6 +250,9 @@ real_start_efi:
#endif
PRINT("- Boot CPU booting -\r\n")
+#ifdef CONFIG_STACK_PROTECTOR
+ bl boot_stack_chk_guard_setup_early
+#endif
bl check_cpu_mode
bl cpu_init
diff --git a/xen/arch/arm/setup.c b/xen/arch/arm/setup.c
index 2e27af4560..3587baab21 100644
--- a/xen/arch/arm/setup.c
+++ b/xen/arch/arm/setup.c
@@ -13,6 +13,7 @@
#include <xen/domain_page.h>
#include <xen/grant_table.h>
#include <xen/types.h>
+#include <xen/stack-protector.h>
#include <xen/string.h>
#include <xen/serial.h>
#include <xen/sched.h>
@@ -359,6 +360,8 @@ void asmlinkage __init start_xen(unsigned long fdt_paddr)
preinit_xen_time();
+ boot_stack_chk_guard_setup();
+
gic_preinit();
uart_init();
--
2.47.1