From 59b7b90668bda12f5af1e302df4e8c906aaa2188 Mon Sep 17 00:00:00 2001
From: Jason Hiser <jdhiser@gmail.com>
Date: Mon, 1 Apr 2019 18:12:21 -0400
Subject: [PATCH] added file-base conversion factor into absptr. may need it
for others in the future
---
unpin_x86.cpp | 25 +++++++++++++++++++------
1 file changed, 19 insertions(+), 6 deletions(-)
diff --git a/unpin_x86.cpp b/unpin_x86.cpp
index aa71218..df11140 100644
--- a/unpin_x86.cpp
+++ b/unpin_x86.cpp
@@ -149,34 +149,47 @@ void UnpinX86_t::HandlePcrelReloc(Instruction_t* from_insn, Relocation_t* reloc)
void UnpinX86_t::HandleAbsptrReloc(Instruction_t* from_insn, Relocation_t* reloc)
{
+ // decode the instruction
const auto disasm=DecodedInstruction_t::factory(from_insn);
const auto operands=disasm->getOperands();
+ // find the memory operand
// push/pop from memory might have a memory operand with no string to represent the implicit stack operand.
const auto the_arg_it=find_if(ALLOF(operands),[](const shared_ptr<DecodedOperand_t>& op){ return op->isMemory() && op->getString()!=""; });
- DataScoop_t* wrt=dynamic_cast<DataScoop_t*>(reloc->getWRT());
+ const auto wrt=dynamic_cast<DataScoop_t*>(reloc->getWRT());
+
+ // assert we found the right thing
assert(wrt);
assert(the_arg_it!=operands.end());
const auto &the_arg=*the_arg_it;
- int disp_offset=disasm->getMemoryDisplacementOffset(the_arg.get(),from_insn);
- int disp_size=the_arg->getMemoryDisplacementEncodingSize();
+ // extract the info about where the displacement encoding is
+ const auto disp_offset = uint32_t(disasm->getMemoryDisplacementOffset(the_arg.get(),from_insn));
+ const auto disp_size = uint32_t(the_arg->getMemoryDisplacementEncodingSize());
assert(disp_size==4);
assert(0<disp_offset && (int64_t)disp_offset<=(int64_t)from_insn->getDataBits().size() - disp_size);
assert(reloc->getWRT());
- unsigned int new_disp=the_arg->getMemoryDisplacement() + wrt->getStart()->getVirtualOffset();
+ // calculate the new displcement
+ const auto new_disp=uint32_t(the_arg->getMemoryDisplacement() + wrt->getStart()->getVirtualOffset() + reloc->getAddend() - firp.getArchitecture()->getFileBase());
+
+ // update the instruction
from_insn->setDataBits(from_insn->getDataBits().replace(disp_offset, disp_size, (char*)&new_disp, disp_size));
+
// update the instruction in the memory space.
- IRDB_SDK::VirtualOffset_t from_insn_location=locMap[from_insn];
+ const auto from_insn_location=locMap[from_insn];
for(unsigned int i=0;i<from_insn->getDataBits().size();i++)
{
- unsigned char newbyte=from_insn->getDataBits()[i];
+ const auto newbyte=from_insn->getDataBits()[i];
ms[from_insn_location+i]=newbyte;
//cout<<"Updating push["<<i<<"] from "<<hex<<oldbyte<<" to "<<newbyte<<endl;
}
+
+ // decode again for logging
const auto disasm2=DecodedInstruction_t::factory(from_insn);
+
+ // log
cout<<"unpin:absptr_to_scoop:Converting "<<hex<<from_insn->getBaseID()<<":"<<disasm->getDisassembly()
<<" to "<<disasm2->getDisassembly() <<" for scoop: "<<wrt->getName()<<endl;
}
--
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