diff options
Diffstat (limited to 'coroutine/arm64/Context.S')
| -rw-r--r-- | coroutine/arm64/Context.S | 153 |
1 files changed, 120 insertions, 33 deletions
diff --git a/coroutine/arm64/Context.S b/coroutine/arm64/Context.S index 07d50d30df..ce219c0c4d 100644 --- a/coroutine/arm64/Context.S +++ b/coroutine/arm64/Context.S @@ -6,7 +6,6 @@ ## #define TOKEN_PASTE(x,y) x##y -#define PREFIXED_SYMBOL(prefix,name) TOKEN_PASTE(prefix,name) #if defined(__APPLE__) #define x29 fp @@ -18,26 +17,63 @@ .align 2 #endif -.global PREFIXED_SYMBOL(SYMBOL_PREFIX,coroutine_transfer) -PREFIXED_SYMBOL(SYMBOL_PREFIX,coroutine_transfer): +#if defined(__ARM_FEATURE_PAC_DEFAULT) && (__ARM_FEATURE_PAC_DEFAULT & 0x02) != 0 +# error "-mbranch-protection flag specified b-key but Context.S does not support this" +#endif + +#if defined(_WIN32) +## Add more space for certain TEB values on each stack +#define TEB_OFFSET 0x20 +#else +#define TEB_OFFSET 0x00 +#endif + +## NOTE(PAC): Use we HINT mnemonics instead of PAC mnemonics to +## keep compatibility with those assemblers that don't support PAC. +## +## See "Providing protection for complex software" for more details about PAC/BTI +## https://developer.arm.com/architectures/learn-the-architecture/providing-protection-for-complex-software + +.global PREFIXED_SYMBOL(coroutine_transfer) +PREFIXED_SYMBOL(coroutine_transfer): +#if defined(__ARM_FEATURE_PAC_DEFAULT) && (__ARM_FEATURE_PAC_DEFAULT != 0) + # paciasp (it also acts as BTI landing pad, so no need to insert BTI also) + hint #25 +#elif defined(__ARM_FEATURE_BTI_DEFAULT) && (__ARM_FEATURE_BTI_DEFAULT != 0) + # For the case PAC is not enabled but BTI is. + # bti c + hint #34 +#endif # Make space on the stack for caller registers - sub sp, sp, 0xb0 + sub sp, sp, 0xa0 + TEB_OFFSET # Save caller registers - stp d8, d9, [sp, 0x00] - stp d10, d11, [sp, 0x10] - stp d12, d13, [sp, 0x20] - stp d14, d15, [sp, 0x30] - stp x19, x20, [sp, 0x40] - stp x21, x22, [sp, 0x50] - stp x23, x24, [sp, 0x60] - stp x25, x26, [sp, 0x70] - stp x27, x28, [sp, 0x80] - stp x29, x30, [sp, 0x90] - - # Save return address - str x30, [sp, 0xa0] + stp d8, d9, [sp, 0x00 + TEB_OFFSET] + stp d10, d11, [sp, 0x10 + TEB_OFFSET] + stp d12, d13, [sp, 0x20 + TEB_OFFSET] + stp d14, d15, [sp, 0x30 + TEB_OFFSET] + stp x19, x20, [sp, 0x40 + TEB_OFFSET] + stp x21, x22, [sp, 0x50 + TEB_OFFSET] + stp x23, x24, [sp, 0x60 + TEB_OFFSET] + stp x25, x26, [sp, 0x70 + TEB_OFFSET] + stp x27, x28, [sp, 0x80 + TEB_OFFSET] + stp x29, x30, [sp, 0x90 + TEB_OFFSET] + +#if defined(_WIN32) + # Save certain values from Thread Environment Block (TEB) + # x18 points to the TEB on Windows + # Read TeStackBase and TeStackLimit at ksarm64.h from TEB + ldp x5, x6, [x18, #0x08] + # Save them + stp x5, x6, [sp, #0x00] + # Read TeDeallocationStack at ksarm64.h from TEB + ldr x5, [x18, #0x1478] + # Read TeFiberData at ksarm64.h from TEB + ldr x6, [x18, #0x20] + # Save current fiber data and deallocation stack + stp x5, x6, [sp, #0x10] +#endif # Save stack pointer to x0 (first argument) mov x2, sp @@ -47,27 +83,78 @@ PREFIXED_SYMBOL(SYMBOL_PREFIX,coroutine_transfer): ldr x3, [x1, 0] mov sp, x3 +#if defined(_WIN32) + # Restore stack base and limit + ldp x5, x6, [sp, #0x00] + # Write TeStackBase and TeStackLimit at ksarm64.h to TEB + stp x5, x6, [x18, #0x08] + # Restore fiber data and deallocation stack + ldp x5, x6, [sp, #0x10] + # Write TeDeallocationStack at ksarm64.h to TEB + str x5, [x18, #0x1478] + # Write TeFiberData at ksarm64.h to TEB + str x6, [x18, #0x20] +#endif + # Restore caller registers - ldp d8, d9, [sp, 0x00] - ldp d10, d11, [sp, 0x10] - ldp d12, d13, [sp, 0x20] - ldp d14, d15, [sp, 0x30] - ldp x19, x20, [sp, 0x40] - ldp x21, x22, [sp, 0x50] - ldp x23, x24, [sp, 0x60] - ldp x25, x26, [sp, 0x70] - ldp x27, x28, [sp, 0x80] - ldp x29, x30, [sp, 0x90] - - # Load return address into x4 - ldr x4, [sp, 0xa0] + ldp d8, d9, [sp, 0x00 + TEB_OFFSET] + ldp d10, d11, [sp, 0x10 + TEB_OFFSET] + ldp d12, d13, [sp, 0x20 + TEB_OFFSET] + ldp d14, d15, [sp, 0x30 + TEB_OFFSET] + ldp x19, x20, [sp, 0x40 + TEB_OFFSET] + ldp x21, x22, [sp, 0x50 + TEB_OFFSET] + ldp x23, x24, [sp, 0x60 + TEB_OFFSET] + ldp x25, x26, [sp, 0x70 + TEB_OFFSET] + ldp x27, x28, [sp, 0x80 + TEB_OFFSET] + ldp x29, x30, [sp, 0x90 + TEB_OFFSET] # Pop stack frame - add sp, sp, 0xb0 + add sp, sp, 0xa0 + TEB_OFFSET - # Jump to return address (in x4) - ret x4 +#if defined(__ARM_FEATURE_PAC_DEFAULT) && (__ARM_FEATURE_PAC_DEFAULT != 0) + # autiasp: Authenticate x30 (LR) with SP and key A + hint #29 +#endif + + # Jump to return address (in x30) + ret #if defined(__linux__) && defined(__ELF__) .section .note.GNU-stack,"",%progbits #endif + +#if (defined(__ARM_FEATURE_BTI_DEFAULT) && __ARM_FEATURE_BTI_DEFAULT != 0) || (defined(__ARM_FEATURE_PAC_DEFAULT) && __ARM_FEATURE_PAC_DEFAULT != 0) +#if defined(__ELF__) +/* See "ELF for the Arm 64-bit Architecture (AArch64)" + https://github.com/ARM-software/abi-aa/blob/2023Q3/aaelf64/aaelf64.rst#program-property */ +# define GNU_PROPERTY_AARCH64_FEATURE_1_BTI (1<<0) +# define GNU_PROPERTY_AARCH64_FEATURE_1_PAC (1<<1) + +# if defined(__ARM_FEATURE_BTI_DEFAULT) && __ARM_FEATURE_BTI_DEFAULT != 0 +# define BTI_FLAG GNU_PROPERTY_AARCH64_FEATURE_1_BTI +# else +# define BTI_FLAG 0 +# endif +# if defined(__ARM_FEATURE_PAC_DEFAULT) && __ARM_FEATURE_PAC_DEFAULT != 0 +# define PAC_FLAG GNU_PROPERTY_AARCH64_FEATURE_1_PAC +# else +# define PAC_FLAG 0 +# endif + + # The note section format is described by Note Section in Chapter 5 + # of "System V Application Binary Interface, Edition 4.1". + .pushsection .note.gnu.property, "a" + .p2align 3 + .long 0x4 /* Name size ("GNU\0") */ + .long 0x10 /* Descriptor size */ + .long 0x5 /* Type: NT_GNU_PROPERTY_TYPE_0 */ + .asciz "GNU" /* Name */ + # Begin descriptor + .long 0xc0000000 /* Property type: GNU_PROPERTY_AARCH64_FEATURE_1_AND */ + .long 0x4 /* Property size */ + .long (BTI_FLAG|PAC_FLAG) + .long 0x0 /* 8-byte alignment padding */ + # End descriptor + .popsection +#endif +#endif |