[0/3] Add stack protector

Message

Volodymyr Babchuk Nov. 22, 2024, 9:07 p.m. UTC

Both GCC and Clang support -fstack-protector feature, which add stack
canaries to functions where stack corruption is possible. This series
makes possible to use this feature in Xen. I tested this on ARM64 and
it is working as intended. Tested both with GCC and Clang.

My aim was to enable it on x86 also, but it appears that on x86 GCC
stores canary value in TLS, exactly at fs:40, which is hardcoded. As
Xen does not setup fs register for itself, any attempt to enable stack
protector leads to paging abort.

I also tested build-ability for RISCV platform, but didn't tested that
it does not break anything, so we will need RISCV maintainer's
approval.

Volodymyr Babchuk (3):
  xen: common: add ability to enable stack protector
  xen: arm: enable stack protector feature
  xen: riscv: enable stack protector feature

 Config.mk                            |  2 +-
 stubdom/Makefile                     |  2 ++
 tools/firmware/Rules.mk              |  2 ++
 tools/tests/x86_emulator/testcase.mk |  2 ++
 xen/Makefile                         |  6 ++++++
 xen/arch/arm/Kconfig                 |  1 +
 xen/arch/arm/setup.c                 |  3 +++
 xen/arch/riscv/Kconfig               |  1 +
 xen/arch/riscv/setup.c               |  3 +++
 xen/common/Kconfig                   | 13 ++++++++++++
 xen/common/Makefile                  |  1 +
 xen/common/stack_protector.c         | 16 +++++++++++++++
 xen/include/xen/stack_protector.h    | 30 ++++++++++++++++++++++++++++
 13 files changed, 81 insertions(+), 1 deletion(-)
 create mode 100644 xen/common/stack_protector.c
 create mode 100644 xen/include/xen/stack_protector.h