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Make AE pointer comparisons conservative #1887

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Make AE pointer comparisons conservative #1887

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a77e9f0
Make AE pointer comparisons conservative
bjjwwang Sep 2, 2026
998aaec
Represent AE null pointers in the address domain
Sep 10, 2026
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4 changes: 4 additions & 0 deletions svf/include/AE/Svfexe/AbstractInterpretation.h
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Original file line number Diff line number Diff line change
Expand Up @@ -282,6 +282,10 @@ class AbstractInterpretation

void updateStateOnBinary(const BinaryOPStmt *binary);

IntervalValue comparePointerValues(const CmpStmt *cmp,
const AbstractValue& lhsValue,
const AbstractValue& rhsValue) const;

void updateStateOnCmp(const CmpStmt *cmp);

void updateStateOnLoad(const LoadStmt *load);
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3 changes: 3 additions & 0 deletions svf/lib/AE/Svfexe/AEDetector.cpp
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Expand Up @@ -470,6 +470,9 @@ bool BufOverflowDetector::canSafelyAccessMemory(const SVF::ValVar* value, const
}
for (const auto& addr : ptrVal.getAddrs())
{
// Null cannot safely access a backing memory object.
if (AbstractState::isNullMem(addr))
return false;
NodeID objId = ae.getAbsState(node).getIDFromAddr(addr);
u32_t size = 0;
// if the object is a constant size object, get the size directly
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11 changes: 5 additions & 6 deletions svf/lib/AE/Svfexe/AbsExtAPI.cpp
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Expand Up @@ -235,13 +235,9 @@ void AbsExtAPI::initExtFunMap()
const AbstractValue& ptrVal = ae->getAbsValue(callNode->getArgument(0), callNode);
for (auto addr: ptrVal.getAddrs())
{
if (AbstractState::isBlackHoleObjAddr(addr))
{
}
else
{
if (!AbstractState::isBlackHoleObjAddr(addr) &&
!AbstractState::isNullMem(addr))
as.addToFreedAddrs(addr);
}
}
};
// Add all free-related functions to func_map
Expand Down Expand Up @@ -455,6 +451,9 @@ IntervalValue AbsExtAPI::getStrlen(const ValVar *strValue, const ICFGNode* node)
const AbstractValue& ptrVal = ae->getAbsValue(strValue, node);
for (const auto& addr : ptrVal.getAddrs())
{
// Null has no backing buffer whose size can be inspected.
if (AbstractState::isNullMem(addr))
continue;
NodeID objId = as.getIDFromAddr(addr);
if (svfir->getBaseObject(objId)->isConstantByteSize())
{
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