diff options
| author | Linus Torvalds <torvalds@linux-foundation.org> | 2022-03-27 10:17:23 -0700 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2022-03-27 10:17:23 -0700 |
| commit | 7001052160d172f6de06adeffde24dde9935ece8 (patch) | |
| tree | 65fbc9c0df5a2989b68882ce1d893a0d78134c6a /arch/x86/include/asm/segment.h | |
| parent | f022814633e1c600507b3a99691b4d624c2813f0 (diff) | |
| parent | 3986f65d4f408ce9d0a361e3226a3246a5fb701c (diff) | |
Merge tag 'x86_core_for_5.18_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 CET-IBT (Control-Flow-Integrity) support from Peter Zijlstra:
"Add support for Intel CET-IBT, available since Tigerlake (11th gen),
which is a coarse grained, hardware based, forward edge
Control-Flow-Integrity mechanism where any indirect CALL/JMP must
target an ENDBR instruction or suffer #CP.
Additionally, since Alderlake (12th gen)/Sapphire-Rapids, speculation
is limited to 2 instructions (and typically fewer) on branch targets
not starting with ENDBR. CET-IBT also limits speculation of the next
sequential instruction after the indirect CALL/JMP [1].
CET-IBT is fundamentally incompatible with retpolines, but provides,
as described above, speculation limits itself"
[1] https://www.intel.com/content/www/us/en/developer/articles/technical/software-security-guidance/technical-documentation/branch-history-injection.html
* tag 'x86_core_for_5.18_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (53 commits)
kvm/emulate: Fix SETcc emulation for ENDBR
x86/Kconfig: Only allow CONFIG_X86_KERNEL_IBT with ld.lld >= 14.0.0
x86/Kconfig: Only enable CONFIG_CC_HAS_IBT for clang >= 14.0.0
kbuild: Fixup the IBT kbuild changes
x86/Kconfig: Do not allow CONFIG_X86_X32_ABI=y with llvm-objcopy
x86: Remove toolchain check for X32 ABI capability
x86/alternative: Use .ibt_endbr_seal to seal indirect calls
objtool: Find unused ENDBR instructions
objtool: Validate IBT assumptions
objtool: Add IBT/ENDBR decoding
objtool: Read the NOENDBR annotation
x86: Annotate idtentry_df()
x86,objtool: Move the ASM_REACHABLE annotation to objtool.h
x86: Annotate call_on_stack()
objtool: Rework ASM_REACHABLE
x86: Mark __invalid_creds() __noreturn
exit: Mark do_group_exit() __noreturn
x86: Mark stop_this_cpu() __noreturn
objtool: Ignore extra-symbol code
objtool: Rename --duplicate to --lto
...
Diffstat (limited to 'arch/x86/include/asm/segment.h')
| -rw-r--r-- | arch/x86/include/asm/segment.h | 5 |
1 files changed, 3 insertions, 2 deletions
diff --git a/arch/x86/include/asm/segment.h b/arch/x86/include/asm/segment.h index b228c9d44ee7..656ed6531d03 100644 --- a/arch/x86/include/asm/segment.h +++ b/arch/x86/include/asm/segment.h @@ -4,6 +4,7 @@ #include <linux/const.h> #include <asm/alternative.h> +#include <asm/ibt.h> /* * Constructor for a conventional segment GDT (or LDT) entry. @@ -275,7 +276,7 @@ static inline void vdso_read_cpunode(unsigned *cpu, unsigned *node) * vector has no error code (two bytes), a 'push $vector_number' (two * bytes), and a jump to the common entry code (up to five bytes). */ -#define EARLY_IDT_HANDLER_SIZE 9 +#define EARLY_IDT_HANDLER_SIZE (9 + ENDBR_INSN_SIZE) /* * xen_early_idt_handler_array is for Xen pv guests: for each entry in @@ -283,7 +284,7 @@ static inline void vdso_read_cpunode(unsigned *cpu, unsigned *node) * pop %rcx; pop %r11; jmp early_idt_handler_array[i]; summing up to * max 8 bytes. */ -#define XEN_EARLY_IDT_HANDLER_SIZE 8 +#define XEN_EARLY_IDT_HANDLER_SIZE (8 + ENDBR_INSN_SIZE) #ifndef __ASSEMBLY__ |