Fixed a memory leak

master
xtremegamer1 2 years ago
parent 943de5b10c
commit e2e578bf55

@ -26,7 +26,6 @@ class emu_t {
~emu_t();
bool init();
bool emulate(std::uint32_t vmenter_rva, vm::instrs::vrtn_t& vrtn);
std::vector<uint8_t>& get_il_bytecode();
private:
uc_engine* uc;

@ -82,9 +82,6 @@ bool emu_t::emulate(std::uint32_t vmenter_rva, vm::instrs::vrtn_t& vrtn) {
return false;
}
cc_trace.m_vip = cc_blk->m_vm.vip;
cc_trace.m_vsp = cc_blk->m_vm.vsp;
std::printf("> beginning execution at = %p (%p)\n", rip, rip - m_vm->m_module_base + m_vm->m_image_base);
if ((err = uc_emu_start(uc, rip, 0ull, 0ull, 0ull))) {
std::printf("> error starting emu... reason = %d\n", err);
@ -123,7 +120,8 @@ bool emu_t::emulate(std::uint32_t vmenter_rva, vm::instrs::vrtn_t& vrtn) {
// emulate the branch...
uc_mem_write(uc, vsp, &br, sizeof br);
std::printf("> beginning execution at = %p (%p)\n", rip, rip - m_vm->m_module_base + m_vm->m_image_base);
std::printf("> beginning execution at = %p (%p)\n", blk.m_jmp.rip,
blk.m_jmp.rip - m_vm->m_module_base + m_vm->m_image_base);
if ((err = uc_emu_start(uc, blk.m_jmp.rip, 0ull, 0ull, 0ull))) {
std::printf("> error starting emu... reason = %d\n", err);
return false;
@ -138,7 +136,7 @@ bool emu_t::emulate(std::uint32_t vmenter_rva, vm::instrs::vrtn_t& vrtn) {
// free all virtual code block virtual jmp information...
std::for_each(vrtn.m_blks.begin(), vrtn.m_blks.end(),
[&](vm::instrs::vblk_t& blk) {
if (blk.m_jmp.ctx) uc_context_free(blk.m_jmp.ctx);
if (blk.m_jmp.ctx) uct_context_free(blk.m_jmp.ctx);
if (blk.m_jmp.stack) delete[] blk.m_jmp.stack;
});
@ -259,11 +257,13 @@ bool emu_t::branch_pred_spec_exec(uc_engine* uc, uint64_t address,
if (instr.mnemonic == ZYDIS_MNEMONIC_INVALID) return false;
uc_context* ctx;
uc_context_alloc(uc, &ctx);
uct_context_alloc(uc, &ctx);
uc_context_save(uc, ctx);
// if this is the first instruction of this handler then save the stack...
if (!obj->cc_trace.m_instrs.size()) {
obj->cc_trace.m_vip = obj->cc_blk->m_vm.vip;
obj->cc_trace.m_vsp = obj->cc_blk->m_vm.vsp;
obj->cc_trace.m_stack = new std::uint8_t[STACK_SIZE];
uc_mem_read(uc, STACK_BASE, obj->cc_trace.m_stack, STACK_SIZE);
}
@ -292,15 +292,21 @@ bool emu_t::branch_pred_spec_exec(uc_engine* uc, uint64_t address,
});
if (rva_fetch != obj->cc_trace.m_instrs.rend())
{
for (auto itr = (rva_fetch + 1).base(); itr < obj->cc_trace.m_instrs.end(); itr++)
{
uct_context_free(itr->m_cpu);
}
obj->cc_trace.m_instrs.erase((rva_fetch + 1).base(),
obj->cc_trace.m_instrs.end());
}
const auto vinstr = vm::instrs::determine(obj->cc_trace);
// -- free the trace since we will start a new one...
std::for_each(obj->cc_trace.m_instrs.begin(), obj->cc_trace.m_instrs.end(),
[&](const vm::instrs::emu_instr_t& instr) {
uc_context_free(instr.m_cpu);
uct_context_free(instr.m_cpu);
});
delete[] obj->cc_trace.m_stack;
@ -339,11 +345,13 @@ bool emu_t::code_exec_callback(uc_engine* uc, uint64_t address, uint32_t size,
if (instr.mnemonic == ZYDIS_MNEMONIC_INVALID) return false;
uc_context* ctx;
uc_context_alloc(uc, &ctx);
uct_context_alloc(uc, &ctx);
uc_context_save(uc, ctx);
// if this is the first instruction of this handler then save the stack...
if (!obj->cc_trace.m_instrs.size()) {
obj->cc_trace.m_vip = obj->cc_blk->m_vm.vip;
obj->cc_trace.m_vsp = obj->cc_blk->m_vm.vsp;
obj->cc_trace.m_stack = new std::uint8_t[STACK_SIZE];
obj->cc_trace.m_begin = address;
uc_mem_read(uc, STACK_BASE, obj->cc_trace.m_stack, STACK_SIZE);
@ -373,8 +381,14 @@ bool emu_t::code_exec_callback(uc_engine* uc, uint64_t address, uint32_t size,
});
if (rva_fetch != obj->cc_trace.m_instrs.rend())
{
for (auto itr = (rva_fetch + 1).base(); itr < --obj->cc_trace.m_instrs.end(); ++itr)
{
uct_context_free(itr->m_cpu);
}
obj->cc_trace.m_instrs.erase((rva_fetch + 1).base(),
--obj->cc_trace.m_instrs.end());
}
// set the virtual code block vip address information...
if (!obj->cc_blk->m_vip.rva || !obj->cc_blk->m_vip.img_based) {
@ -389,10 +403,10 @@ bool emu_t::code_exec_callback(uc_engine* uc, uint64_t address, uint32_t size,
});
uc_context* backup;
uc_context_alloc(uc, &backup);
uct_context_alloc(uc, &backup);
uc_context_save(uc, backup);
uc_context_restore(uc, (--vip_write)->m_cpu);
std::uintptr_t vip_addr = 0ull;
uc_reg_read(uc, vm::instrs::reg_map[obj->cc_trace.m_vip], &vip_addr);
@ -400,7 +414,7 @@ bool emu_t::code_exec_callback(uc_engine* uc, uint64_t address, uint32_t size,
obj->cc_blk->m_vip.img_based = vip_addr += obj->m_vm->m_image_base;
uc_context_restore(uc, backup);
uc_context_free(backup);
uct_context_free(backup);
} else {
const auto vinstr = vm::instrs::determine(obj->cc_trace);
if (vinstr.mnemonic != vm::instrs::mnemonic_t::unknown) {
@ -430,8 +444,8 @@ bool emu_t::code_exec_callback(uc_engine* uc, uint64_t address, uint32_t size,
"> err: please define the following vm handler (at = %p):\n",
(obj->cc_trace.m_begin - obj->m_vm->m_module_base) +
obj->m_vm->m_image_base);
std::printf("vsp: %s, vip: %s\n", ZydisRegisterGetString(obj->cc_blk->m_vm.vsp),
ZydisRegisterGetString(obj->cc_blk->m_vm.vip));
std::printf("vsp: %s, vip: %s\n", ZydisRegisterGetString(obj->cc_trace.m_vsp),
ZydisRegisterGetString(obj->cc_trace.m_vip));
vm::utils::print(inst_stream);
uc_emu_stop(uc);
return false;
@ -442,8 +456,8 @@ bool emu_t::code_exec_callback(uc_engine* uc, uint64_t address, uint32_t size,
uc_context *backup, *copy;
// backup current unicorn-engine context...
uc_context_alloc(uc, &backup);
uc_context_alloc(uc, &copy);
uct_context_alloc(uc, &backup);
uct_context_alloc(uc, &copy);
uc_context_save(uc, backup);
// make a copy of the first cpu context of the jmp handler...
@ -452,7 +466,7 @@ bool emu_t::code_exec_callback(uc_engine* uc, uint64_t address, uint32_t size,
// restore the unicorn-engine context... also free the backup...
uc_context_restore(uc, backup);
uc_context_free(backup);
uct_context_free(backup);
// set current code block virtual jmp instruction information...
obj->cc_blk->m_jmp.ctx = copy;
@ -474,7 +488,7 @@ bool emu_t::code_exec_callback(uc_engine* uc, uint64_t address, uint32_t size,
// -- free the trace since we will start a new one...
std::for_each(obj->cc_trace.m_instrs.begin(), obj->cc_trace.m_instrs.end(),
[&](const vm::instrs::emu_instr_t& instr) {
uc_context_free(instr.m_cpu);
uct_context_free(instr.m_cpu);
});
delete[] obj->cc_trace.m_stack;
@ -521,7 +535,7 @@ bool emu_t::legit_branch(vm::instrs::vblk_t& vblk, std::uintptr_t branch_addr) {
// make a backup of the current emulation state...
uc_context* backup;
uc_context_alloc(uc, &backup);
uct_context_alloc(uc, &backup);
uc_context_save(uc, backup);
std::uint8_t* stack = new std::uint8_t[STACK_SIZE];
uc_mem_read(uc, STACK_BASE, stack, STACK_SIZE);
@ -542,7 +556,7 @@ bool emu_t::legit_branch(vm::instrs::vblk_t& vblk, std::uintptr_t branch_addr) {
// restore original cpu and stack...
uc_mem_write(uc, STACK_BASE, stack, STACK_SIZE);
uc_context_restore(uc, backup);
uc_context_free(backup);
uct_context_free(backup);
delete[] stack;
// add normal execution callback back...

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