Index: lib/interception/interception_win.cc =================================================================== --- lib/interception/interception_win.cc +++ lib/interception/interception_win.cc @@ -229,10 +229,6 @@ _memset((void*)from, 0xCC, (size_t)size); } -static void CopyInstructions(uptr from, uptr to, uptr size) { - _memcpy((void*)from, (void*)to, (size_t)size); -} - static void WriteJumpInstruction(uptr from, uptr target) { if (!DistanceIsWithin2Gig(from + kJumpInstructionLength, target)) InterceptionFailed(); @@ -384,7 +380,7 @@ } // Returns 0 on error. -static size_t GetInstructionSize(uptr address) { +static size_t GetInstructionSize(uptr address, size_t* rel_offset = nullptr) { switch (*(u64*)address) { case 0x90909090909006EB: // stub: jmp over 6 x nop. return 8; @@ -505,8 +501,11 @@ // mov rax, QWORD PTR [rip + XXXXXXXX] case 0x25ff48: // 48 ff 25 XX XX XX XX : // rex.W jmp QWORD PTR [rip + XXXXXXXX] - // Instructions having offset relative to 'rip' cannot be copied. - return 0; + + // Instructions having offset relative to 'rip' need offset adjustment. + if (rel_offset) + *rel_offset = 3; + return 7; case 0x2444c7: // C7 44 24 XX YY YY YY YY // mov dword ptr [rsp + XX], YYYYYYYY @@ -580,6 +579,29 @@ return cursor; } +static bool CopyInstructions(uptr to, uptr from, size_t size) { + size_t cursor = 0; + while (cursor != size) { + size_t rel_offset = 0; + size_t instruction_size = GetInstructionSize(from + cursor, &rel_offset); + _memcpy((void*)(to + cursor), (void*)(from + cursor), + (size_t)instruction_size); + if (rel_offset) { + uptr delta = to - from; + uptr relocated_offset = *(u32*)(to + cursor + rel_offset) - delta; +#if SANITIZER_WINDOWS64 + if (relocated_offset + 0x80000000U >= 0xFFFFFFFFU) + return false; +#endif + *(u32*)(to + cursor + rel_offset) = relocated_offset; + } + cursor += instruction_size; + } + + return true; +} + + #if !SANITIZER_WINDOWS64 bool OverrideFunctionWithDetour( uptr old_func, uptr new_func, uptr *orig_old_func) { @@ -670,7 +692,8 @@ uptr trampoline = AllocateMemoryForTrampoline(old_func, trampoline_length); if (!trampoline) return false; - CopyInstructions(trampoline, old_func, instruction_size); + if (!CopyInstructions(trampoline, old_func, instruction_size)) + return false; WriteDirectBranch(trampoline + instruction_size, old_func + instruction_size); *orig_old_func = trampoline; @@ -719,7 +742,8 @@ uptr trampoline = AllocateMemoryForTrampoline(old_func, trampoline_length); if (!trampoline) return false; - CopyInstructions(trampoline, old_func, instructions_length); + if (!CopyInstructions(trampoline, old_func, instructions_length)) + return false; WriteDirectBranch(trampoline + instructions_length, old_func + instructions_length); *orig_old_func = trampoline;