From 48d642a310b96e68465d724644510d3f6e381b2c Mon Sep 17 00:00:00 2001 From: Ard Biesheuvel Date: Mon, 27 Mar 2023 12:10:06 +0200 Subject: ArmPkg: Emit BTI opcodes when BTI codegen is enabled When building with -mbranch-protection=bti, which affects the compiler codegen only, ensure that the assembler based codegen is aligned with this, by emitting the BTI C opcode at the start of each exported function. While most exported functions are not in fact ever called indirectly, whether or not this is the case is a property of the caller so annotating every exported function is a reasonable default. While at it, fix two occurrences in ArmPkg of exported functions that did not use the ASM_FUNC() macro. Signed-off-by: Ard Biesheuvel Reviewed-by: Leif Lindholm Reviewed-by: Oliver Smith-Denny --- ArmPkg/Include/AsmMacroIoLibV8.h | 3 ++- ArmPkg/Library/ArmExceptionLib/AArch64/ExceptionSupport.S | 3 +-- ArmPkg/Library/ArmSvcLib/AArch64/ArmSvc.S | 6 +++--- 3 files changed, 6 insertions(+), 6 deletions(-) diff --git a/ArmPkg/Include/AsmMacroIoLibV8.h b/ArmPkg/Include/AsmMacroIoLibV8.h index 2c2b1cabd0..135aaeca5d 100644 --- a/ArmPkg/Include/AsmMacroIoLibV8.h +++ b/ArmPkg/Include/AsmMacroIoLibV8.h @@ -38,7 +38,8 @@ .global Name ; \ .section #Section, "ax" ; \ .type Name, %function ; \ - Name: + Name: ; \ + AARCH64_BTI(c) #define ASM_FUNC(Name) _ASM_FUNC(ASM_PFX(Name), .text. ## Name) diff --git a/ArmPkg/Library/ArmExceptionLib/AArch64/ExceptionSupport.S b/ArmPkg/Library/ArmExceptionLib/AArch64/ExceptionSupport.S index 9202952ee9..cd9437b6aa 100644 --- a/ArmPkg/Library/ArmExceptionLib/AArch64/ExceptionSupport.S +++ b/ArmPkg/Library/ArmExceptionLib/AArch64/ExceptionSupport.S @@ -94,7 +94,6 @@ GCC_ASM_EXPORT(ExceptionHandlersEnd) GCC_ASM_EXPORT(CommonCExceptionHandler) -GCC_ASM_EXPORT(RegisterEl0Stack) .text @@ -387,6 +386,6 @@ ASM_PFX(CommonExceptionEntry): eret -ASM_PFX(RegisterEl0Stack): +ASM_FUNC(RegisterEl0Stack) msr sp_el0, x0 ret diff --git a/ArmPkg/Library/ArmSvcLib/AArch64/ArmSvc.S b/ArmPkg/Library/ArmSvcLib/AArch64/ArmSvc.S index 1a7c10cb79..bdba9d7fe9 100644 --- a/ArmPkg/Library/ArmSvcLib/AArch64/ArmSvc.S +++ b/ArmPkg/Library/ArmSvcLib/AArch64/ArmSvc.S @@ -5,12 +5,12 @@ // // +#include + .text .align 3 -GCC_ASM_EXPORT(ArmCallSvc) - -ASM_PFX(ArmCallSvc): +ASM_FUNC(ArmCallSvc) // Push frame pointer and return address on the stack stp x29, x30, [sp, #-32]! mov x29, sp -- cgit v1.2.3