diff options
Diffstat (limited to 'contrib/llvm/tools/clang/lib/StaticAnalyzer/Checkers/MmapWriteExecChecker.cpp')
-rw-r--r-- | contrib/llvm/tools/clang/lib/StaticAnalyzer/Checkers/MmapWriteExecChecker.cpp | 93 |
1 files changed, 0 insertions, 93 deletions
diff --git a/contrib/llvm/tools/clang/lib/StaticAnalyzer/Checkers/MmapWriteExecChecker.cpp b/contrib/llvm/tools/clang/lib/StaticAnalyzer/Checkers/MmapWriteExecChecker.cpp deleted file mode 100644 index 270efede8385..000000000000 --- a/contrib/llvm/tools/clang/lib/StaticAnalyzer/Checkers/MmapWriteExecChecker.cpp +++ /dev/null @@ -1,93 +0,0 @@ -// MmapWriteExecChecker.cpp - Check for the prot argument -----------------===// -// -// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. -// See https://llvm.org/LICENSE.txt for license information. -// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception -// -//===----------------------------------------------------------------------===// -// -// This checker tests the 3rd argument of mmap's calls to check if -// it is writable and executable in the same time. It's somehow -// an optional checker since for example in JIT libraries it is pretty common. -// -//===----------------------------------------------------------------------===// - -#include "clang/StaticAnalyzer/Checkers/BuiltinCheckerRegistration.h" - -#include "clang/StaticAnalyzer/Core/BugReporter/BugType.h" -#include "clang/StaticAnalyzer/Core/Checker.h" -#include "clang/StaticAnalyzer/Core/CheckerManager.h" -#include "clang/StaticAnalyzer/Core/PathSensitive/CallEvent.h" -#include "clang/StaticAnalyzer/Core/PathSensitive/CheckerContext.h" - -using namespace clang; -using namespace ento; -using llvm::APSInt; - -namespace { -class MmapWriteExecChecker : public Checker<check::PreCall> { - CallDescription MmapFn; - CallDescription MprotectFn; - static int ProtWrite; - static int ProtExec; - static int ProtRead; - mutable std::unique_ptr<BugType> BT; -public: - MmapWriteExecChecker() : MmapFn("mmap", 6), MprotectFn("mprotect", 3) {} - void checkPreCall(const CallEvent &Call, CheckerContext &C) const; - int ProtExecOv; - int ProtReadOv; -}; -} - -int MmapWriteExecChecker::ProtWrite = 0x02; -int MmapWriteExecChecker::ProtExec = 0x04; -int MmapWriteExecChecker::ProtRead = 0x01; - -void MmapWriteExecChecker::checkPreCall(const CallEvent &Call, - CheckerContext &C) const { - if (Call.isCalled(MmapFn) || Call.isCalled(MprotectFn)) { - SVal ProtVal = Call.getArgSVal(2); - Optional<nonloc::ConcreteInt> ProtLoc = ProtVal.getAs<nonloc::ConcreteInt>(); - int64_t Prot = ProtLoc->getValue().getSExtValue(); - if (ProtExecOv != ProtExec) - ProtExec = ProtExecOv; - if (ProtReadOv != ProtRead) - ProtRead = ProtReadOv; - - // Wrong settings - if (ProtRead == ProtExec) - return; - - if ((Prot & (ProtWrite | ProtExec)) == (ProtWrite | ProtExec)) { - if (!BT) - BT.reset(new BugType(this, "W^X check fails, Write Exec prot flags set", "Security")); - - ExplodedNode *N = C.generateNonFatalErrorNode(); - if (!N) - return; - - auto Report = llvm::make_unique<BugReport>( - *BT, "Both PROT_WRITE and PROT_EXEC flags are set. This can " - "lead to exploitable memory regions, which could be overwritten " - "with malicious code", N); - Report->addRange(Call.getArgSourceRange(2)); - C.emitReport(std::move(Report)); - } - } -} - -void ento::registerMmapWriteExecChecker(CheckerManager &mgr) { - MmapWriteExecChecker *Mwec = - mgr.registerChecker<MmapWriteExecChecker>(); - Mwec->ProtExecOv = - mgr.getAnalyzerOptions() - .getCheckerIntegerOption(Mwec, "MmapProtExec"); - Mwec->ProtReadOv = - mgr.getAnalyzerOptions() - .getCheckerIntegerOption(Mwec, "MmapProtRead"); -} - -bool ento::shouldRegisterMmapWriteExecChecker(const LangOptions &LO) { - return true; -} |