This series introduces CET - Shadow stack At the high level, shadow stack is: Allocated from a task's address space with vm_flags VM_SHSTK; Its PTEs must be read-only and dirty; Fixed sized, but the default size can be changed by sys admin. For a forked child, the shadow stack is duplicated when the next shadow stack access takes place. For a pthread child, a new shadow stack is allocated. The signal handler uses the same shadow stack as the main program. Yu-cheng Yu (10): x86/cet: User-mode shadow stack support x86/cet: Introduce WRUSS instruction x86/cet: Signal handling for shadow stack x86/cet: Handle thread shadow stack x86/cet: ELF header parsing of Control Flow Enforcement x86/cet: Add arch_prctl functions for shadow stack mm: Prevent mprotect from changing shadow stack mm: Prevent mremap of shadow stack mm: Prevent madvise from changing shadow stack mm: Prevent munmap and remap_file_pages of shadow stack arch/x86/Kconfig | 4 + arch/x86/ia32/ia32_signal.c | 5 + arch/x86/include/asm/cet.h | 48 ++++++ arch/x86/include/asm/disabled-features.h | 8 +- arch/x86/include/asm/elf.h | 5 + arch/x86/include/asm/mmu_context.h | 3 + arch/x86/include/asm/msr-index.h | 14 ++ arch/x86/include/asm/processor.h | 5 + arch/x86/include/asm/special_insns.h | 44 +++++ arch/x86/include/uapi/asm/elf_property.h | 16 ++ arch/x86/include/uapi/asm/prctl.h | 15 ++ arch/x86/include/uapi/asm/sigcontext.h | 4 + arch/x86/kernel/Makefile | 4 + arch/x86/kernel/cet.c | 224 ++++++++++++++++++++++++ arch/x86/kernel/cet_prctl.c | 203 ++++++++++++++++++++++ arch/x86/kernel/cpu/common.c | 24 +++ arch/x86/kernel/elf.c | 236 ++++++++++++++++++++++++++ arch/x86/kernel/process.c | 10 ++ arch/x86/kernel/process_64.c | 7 + arch/x86/kernel/signal.c | 11 ++ arch/x86/lib/x86-opcode-map.txt | 2 +- arch/x86/mm/fault.c | 13 +- fs/binfmt_elf.c | 16 ++ fs/proc/task_mmu.c | 3 + include/uapi/linux/elf.h | 1 + mm/madvise.c | 9 + mm/mmap.c | 13 ++ mm/mprotect.c | 9 + mm/mremap.c | 5 +- tools/objtool/arch/x86/lib/x86-opcode-map.txt | 2 +- 30 files changed, 958 insertions(+), 5 deletions(-) create mode 100644 arch/x86/include/asm/cet.h create mode 100644 arch/x86/include/uapi/asm/elf_property.h create mode 100644 arch/x86/kernel/cet.c create mode 100644 arch/x86/kernel/cet_prctl.c create mode 100644 arch/x86/kernel/elf.c -- 2.15.1
