github / github/codeql

UAF not flagged

未關閉
#15,806 2 則留言 0 個 reaction 已指派 1 人 已被 @mbg 認領 在 GitHub 檢視
C++ question
主要語言
CodeQL
星號
10.1k
分支
2.1k
平均合併
2 天 15 小時
30 天內合併 PR
141

描述

I borrowed the query from UseAfterFree.ql present in CodeQL repo and modified to include a custom free function, but the query is not flagging UAF.

```
import cpp
import semmle.code.cpp.dataflow.new.DataFlow
import semmle.code.cpp.ir.IR
import semmle.code.cpp.security.flowafterfree.FlowAfterFree
import semmle.code.cpp.security.flowafterfree.UseAfterFree
import UseAfterFreeTrace::PathGraph

module UseAfterFreeParam implements FlowFromFreeParamSig {
predicate isSink = isUse/2;

predicate isExcluded = isExcludedMmFreePageFromMdl/2;

predicate sourceSinkIsRelated = defaultSourceSinkIsRelated/2;
}

import UseAfterFreeParam

module UseAfterFreeTrace = FlowFromFree;

class FreeAddrInfo extends DeallocationExpr,FunctionCall {

FreeAddrInfo() {
this.getTarget().hasGlobalName("freeaddrinfo")
}

override Expr getFreedExpr(){
result = this.getArgument(0)
}
}

from UseAfterFreeTrace::PathNode source, UseAfterFreeTrace::PathNode sink, FreeAddrInfo dealloc
where
UseAfterFreeTrace::flowPath(source, sink) and
isFree(source.getNode(), _, _, dealloc)
select sink.getNode(), source, sink, "Memory may have been previously freed by $@.", dealloc,
dealloc.toString()
```

I'm trying to analyse https://nvd.nist.gov/vuln/detail/CVE-2021-38383

貢獻指南

開啟貢獻指南

評估

這個 Issue 還沒有評估資料。

把新 issue 寄到你的電子郵件信箱

精選適合新手參與的 GitHub issue 摘要。