From 748c0a331ed666914abb4f8164718944dcc70529 Mon Sep 17 00:00:00 2001
From: Jason Hiser <jdhiser@gmail.com>
Date: Tue, 25 Dec 2018 09:39:41 -0500
Subject: [PATCH] updating for pcrel on arm
---
SConscript | 7 +--
push64_relocs.cpp | 133 ++++++++++++++++++++++++++++------------------
2 files changed, 82 insertions(+), 58 deletions(-)
diff --git a/SConscript b/SConscript
index 5563464dc..5d33b7f9f 100644
--- a/SConscript
+++ b/SConscript
@@ -20,11 +20,6 @@ myenv.Replace(ZIPR_SDK=os.environ['ZIPR_SDK'])
myenv.Replace(ZIPR_INSTALL=os.environ['ZIPR_INSTALL'])
myenv.Replace(do_cgc=ARGUMENTS.get("do_cgc",0))
-if 'do_cgc' in env and int(env['do_cgc']) == 1:
- myenv.Append(CFLAGS=" -DCGC ")
- myenv.Append(CCFLAGS=" -DCGC ")
-
-
files= '''
@@ -50,7 +45,7 @@ libpath='''
'''
if sysname != "SunOS":
- myenv.Append(CCFLAGS=" -Wall -Werror ")
+ myenv.Append(CCFLAGS=" -Wall -Werror -fmax-errors=2")
myenv.Append(CXXFLAGS=" -std=c++11 ")
myenv=myenv.Clone(CPPPATH=Split(cpppath), LIBS=Split(libs), LIBPATH=Split(libpath), SHLIBSUFFIX=".zpi", SHLIBPREFIX="")
diff --git a/push64_relocs.cpp b/push64_relocs.cpp
index d4ba500e5..c68932900 100644
--- a/push64_relocs.cpp
+++ b/push64_relocs.cpp
@@ -314,18 +314,7 @@ void Push64Relocs_t::UpdatePush64Adds()
// caution, side effect in if statement.
else if ( (reloc = FindPcrelRelocation(insn)) != NULL && reloc->GetWRT()==NULL)
{
-// would consider updating this if statement to be a function call for simplicity/readability.
- uint8_t memory_offset = 0;
- int32_t existing_offset = 0;
- int32_t new_offset = 0;
- uint32_t insn_addr = 0;
- int existing_offset_size = 0;
- uint8_t *insn_bytes = NULL;
- int insn_bytes_len = 0;
- //DISASM d;
- //ARGTYPE *arg=NULL;
-#if 1
- insn_addr = final_insn_locations[insn];
+ const auto insn_addr = final_insn_locations[insn];
if (insn_addr == 0)
{
if (m_verbose)
@@ -334,51 +323,91 @@ void Push64Relocs_t::UpdatePush64Adds()
}
assert(insn_addr != 0);
- insn_bytes_len = sizeof(uint8_t)*insn->GetDataBits().length();
- insn_bytes=(uint8_t*)malloc(insn_bytes_len);
+ const auto insn_bytes_len = sizeof(uint8_t)*insn->GetDataBits().length();
+ uint8_t insn_bytes[insn_bytes_len]={};
memcpy(insn_bytes, insn->GetDataBits().c_str(), insn_bytes_len);
- DecodedInstruction_t d(insn);
- /* Disassemble(insn,d);
-
- if(arg_has_relative(d.Argument1))
- arg=&d.Argument1;
- if(arg_has_relative(d.Argument2))
- arg=&d.Argument2;
- if(arg_has_relative(d.Argument3))
- arg=&d.Argument3;
- assert(arg);
- */
+ const auto d=DecodedInstruction_t(insn);
const auto operands=d.getOperands();
- const auto arg_it=find_if(ALLOF(operands),[](const DecodedOperand_t& op) { return op.isMemory() && op.isPcrel(); });
+ const auto arg_it=find_if(ALLOF(operands),[](const DecodedOperand_t& op) { return op.isPcrel(); });
assert(arg_it!=operands.end());
const auto arg=*arg_it;
-
- memory_offset = d.getMemoryDisplacementOffset(arg, insn); // arg->Memory.DisplacementAddr-d.EIP;
- existing_offset_size = arg.getMemoryDisplacementEncodingSize(); // arg->Memory.DisplacementSize;
- assert(memory_offset>=0 && memory_offset <=15 &&
- (existing_offset_size==1 ||
- existing_offset_size==2 ||
- existing_offset_size==4 ||
- existing_offset_size==8));
-
- memcpy((uint8_t*)&existing_offset,
- (uint8_t*)&insn_bytes[memory_offset],
- existing_offset_size);
-
- new_offset = existing_offset-insn_addr;
- if (m_verbose)
- cout << "Relocating a pcrel relocation with 0x"
- << std::hex << existing_offset
- << " existing offset at 0x"
- << insn_addr << "." << endl
- << "Based on: " << d.getDisassembly() /*CompleteInstr*/ << endl
- << "New address: 0x" << std::hex << new_offset << endl;
-
- m_memory_space.PlopBytes(insn_addr+memory_offset,
- (const char*)&new_offset,
- existing_offset_size);
-#endif
+ const auto mt=m_firp.GetArchitecture()->getMachineType();
+
+ if(mt==admtX86_64 || mt==admtI386)
+ {
+ assert(arg.isMemory()); // only memory operands have pcrel in x86.
+ auto memory_offset = d.getMemoryDisplacementOffset(arg, insn);
+ auto existing_offset_size = arg.getMemoryDisplacementEncodingSize();
+ assert(memory_offset>=0 && memory_offset <=15);
+ assert(existing_offset_size==1 || existing_offset_size==2 || existing_offset_size==4 || existing_offset_size==8);
+ int32_t existing_offset=0;
+ memcpy((uint8_t*)&existing_offset,
+ (uint8_t*)&insn_bytes[memory_offset],
+ existing_offset_size);
+
+ auto new_offset = existing_offset-insn_addr;
+ if (m_verbose)
+ {
+ cout << "Relocating a pcrel relocation with 0x"
+ << hex << existing_offset
+ << " existing offset at 0x"
+ << insn_addr << "." << endl;
+ cout << "Based on: " << d.getDisassembly() << endl
+ << "New address: 0x" << hex << new_offset << endl;
+ }
+
+ m_memory_space.PlopBytes(insn_addr+memory_offset,
+ (const char*)&new_offset,
+ existing_offset_size);
+ }
+ else if(mt==admtAarch64)
+ {
+ const auto mnemonic=d.getMnemonic();
+ const auto is_adr_type=mnemonic=="adr" || mnemonic=="adrp";
+ const auto full_insn=*(uint32_t*)insn_bytes;
+ const auto mask2 =(1<< 2)-1;
+ const auto mask5 =(1<< 5)-1;
+ const auto mask12=(1<<12)-1;
+ const auto mask19=(1<<19)-1;
+
+ if(is_adr_type)
+ {
+ // adr : 0 immlo2 10000 immhi19 Rd5
+ // adrp: 1 immlo2 10000 immhi19 Rd5
+ const auto op_byte=insn_bytes[3];
+ assert((op_byte&mask5) == 0x10); // sanity check adr(p) opcode bytes.
+ const auto immlo2=(op_byte >> 5)&mask2; // gram immlo2
+ const auto immhi19=(full_insn >> 5)&mask19; // gram immhi19
+ const auto imm21=immhi19<<2 | immlo2; // get full immediate in one field.
+ const auto imm21_ext=(((int64_t)imm21)<<43) >> 43; // sign extend to 64-bit
+ const auto orig_insn_addr=insn->GetAddress()->GetVirtualOffset();
+ const auto orig_insn_pageno=(orig_insn_addr>>12);
+ const auto new_insn_pageno =( insn_addr>>12);
+ const auto new_imm21_ext = imm21_ext + orig_insn_pageno - new_insn_pageno + reloc->GetAddend();
+ // make sure no overflow.
+ assert( ((new_imm21_ext << 43) >> 43) == new_imm21_ext);
+ const auto new_immhi19=new_imm21_ext >> 2;
+ const auto new_immlo2 =new_imm21_ext & mask2;
+ const auto clean_new_insn= full_insn & ~(mask2<<29) & ~ (mask19 << 5);
+ const auto new_insn=clean_new_insn | (new_immlo2 << 29) | (new_immhi19<<5);
+ // put the new instruction in the output
+ m_memory_space.PlopBytes(insn_addr, (const char*)&new_insn, 4);
+
+ if (m_verbose)
+ {
+ cout << "Relocating a pcrel relocation with orig_pageno=" << hex
+ << (orig_insn_pageno << 12) << " offset=(page-pc+" << imm21_ext << ")" << endl;
+ cout << "Based on: " << d.getDisassembly() << " originally at " << orig_insn_addr
+ << " now located at : 0x" << hex << insn_addr << " with offset=(page-pc + "
+ << new_imm21_ext << ")" << endl;
+ }
+ }
+ else
+ assert(0);
+ }
+ else
+ assert(0);
}
}
}
--
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