From c038638ea899d385db15c4d25e0cdce30350babd Mon Sep 17 00:00:00 2001
From: Jason Hiser <jdhiser@gmail.com>
Date: Thu, 23 May 2019 07:13:21 -0400
Subject: [PATCH] minor fixes for instructions that are likely bogus (i.e.,
pcrel insns that access out-of-bounds memory)
---
irdb-libs/ir_builders/fix_calls.cpp | 4 +++-
irdb-libs/libIRDB-util/src/params.cpp | 5 +++++
2 files changed, 8 insertions(+), 1 deletion(-)
diff --git a/irdb-libs/ir_builders/fix_calls.cpp b/irdb-libs/ir_builders/fix_calls.cpp
index 519810db6..ff650611c 100644
--- a/irdb-libs/ir_builders/fix_calls.cpp
+++ b/irdb-libs/ir_builders/fix_calls.cpp
@@ -844,7 +844,9 @@ class FixCalls_t : public TransformStep_t
switch(size)
{
case 4:
- assert( (uintptr_t)(int)newdisp == (uintptr_t)newdisp);
+ // if newdisp is negative (or bigger than 32-bit), then the instruction is accessing invalid memory.
+ // and is likely bogus. we just skip doing any pc-rel for it.
+ if( (uintptr_t)(int32_t)newdisp != (uintptr_t)newdisp) continue;
*(int*)offsetptr=newdisp;
break;
case 1:
diff --git a/irdb-libs/libIRDB-util/src/params.cpp b/irdb-libs/libIRDB-util/src/params.cpp
index 68bab5b3a..a716a283e 100644
--- a/irdb-libs/libIRDB-util/src/params.cpp
+++ b/irdb-libs/libIRDB-util/src/params.cpp
@@ -70,9 +70,14 @@ bool IRDB_SDK::isParameterWrite(const IRDB_SDK::FileIR_t *firp, IRDB_SDK::Instru
if(!d.getOperand(0)->isMemory())
return false;
+ // pcrel instructions aren't to the stack.
+ if(d.getOperand(0)->isPcrel())
+ return false;
+
// check that base reg is esp.
if(!d.getOperand(0)->hasBaseRegister())
return false;
+
if(d.getOperand(0)->getBaseRegister() != 4)
return false;
--
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