Author: chh Date: Wed Aug 16 10:18:16 2017 New Revision: 311024 URL: http://llvm.org/viewvc/llvm-project?rev=311024&view=rev Log: [clang-tidy] Add a close-on-exec check on accept() in Android module.
Summary: accept() is better to be replaced by accept4() with SOCK_CLOEXEC flag to avoid file descriptor leakage. Differential Revision: https://reviews.llvm.org/D35362 Added: clang-tools-extra/trunk/clang-tidy/android/CloexecAcceptCheck.cpp clang-tools-extra/trunk/clang-tidy/android/CloexecAcceptCheck.h clang-tools-extra/trunk/docs/clang-tidy/checks/android-cloexec-accept.rst clang-tools-extra/trunk/test/clang-tidy/android-cloexec-accept.cpp Modified: clang-tools-extra/trunk/clang-tidy/android/AndroidTidyModule.cpp clang-tools-extra/trunk/clang-tidy/android/CMakeLists.txt clang-tools-extra/trunk/docs/ReleaseNotes.rst clang-tools-extra/trunk/docs/clang-tidy/checks/list.rst Modified: clang-tools-extra/trunk/clang-tidy/android/AndroidTidyModule.cpp URL: http://llvm.org/viewvc/llvm-project/clang-tools-extra/trunk/clang-tidy/android/AndroidTidyModule.cpp?rev=311024&r1=311023&r2=311024&view=diff ============================================================================== --- clang-tools-extra/trunk/clang-tidy/android/AndroidTidyModule.cpp (original) +++ clang-tools-extra/trunk/clang-tidy/android/AndroidTidyModule.cpp Wed Aug 16 10:18:16 2017 @@ -10,6 +10,7 @@ #include "../ClangTidy.h" #include "../ClangTidyModule.h" #include "../ClangTidyModuleRegistry.h" +#include "CloexecAcceptCheck.h" #include "CloexecCreatCheck.h" #include "CloexecDupCheck.h" #include "CloexecFopenCheck.h" @@ -29,6 +30,7 @@ namespace android { class AndroidModule : public ClangTidyModule { public: void addCheckFactories(ClangTidyCheckFactories &CheckFactories) override { + CheckFactories.registerCheck<CloexecAcceptCheck>("android-cloexec-accept"); CheckFactories.registerCheck<CloexecCreatCheck>("android-cloexec-creat"); CheckFactories.registerCheck<CloexecDupCheck>("android-cloexec-dup"); CheckFactories.registerCheck<CloexecFopenCheck>("android-cloexec-fopen"); Modified: clang-tools-extra/trunk/clang-tidy/android/CMakeLists.txt URL: http://llvm.org/viewvc/llvm-project/clang-tools-extra/trunk/clang-tidy/android/CMakeLists.txt?rev=311024&r1=311023&r2=311024&view=diff ============================================================================== --- clang-tools-extra/trunk/clang-tidy/android/CMakeLists.txt (original) +++ clang-tools-extra/trunk/clang-tidy/android/CMakeLists.txt Wed Aug 16 10:18:16 2017 @@ -2,6 +2,7 @@ set(LLVM_LINK_COMPONENTS support) add_clang_library(clangTidyAndroidModule AndroidTidyModule.cpp + CloexecAcceptCheck.cpp CloexecCheck.cpp CloexecCreatCheck.cpp CloexecDupCheck.cpp Added: clang-tools-extra/trunk/clang-tidy/android/CloexecAcceptCheck.cpp URL: http://llvm.org/viewvc/llvm-project/clang-tools-extra/trunk/clang-tidy/android/CloexecAcceptCheck.cpp?rev=311024&view=auto ============================================================================== --- clang-tools-extra/trunk/clang-tidy/android/CloexecAcceptCheck.cpp (added) +++ clang-tools-extra/trunk/clang-tidy/android/CloexecAcceptCheck.cpp Wed Aug 16 10:18:16 2017 @@ -0,0 +1,47 @@ +//===--- CloexecAcceptCheck.cpp - clang-tidy-------------------------------===// +// +// The LLVM Compiler Infrastructure +// +// This file is distributed under the University of Illinois Open Source +// License. See LICENSE.TXT for details. +// +//===----------------------------------------------------------------------===// + +#include "CloexecAcceptCheck.h" +#include "clang/AST/ASTContext.h" +#include "clang/ASTMatchers/ASTMatchFinder.h" + +using namespace clang::ast_matchers; + +namespace clang { +namespace tidy { +namespace android { + +void CloexecAcceptCheck::registerMatchers(MatchFinder *Finder) { + auto SockAddrPointerType = + hasType(pointsTo(recordDecl(isStruct(), hasName("sockaddr")))); + auto SockLenPointerType = hasType(pointsTo(namedDecl(hasName("socklen_t")))); + + registerMatchersImpl(Finder, + functionDecl(returns(isInteger()), hasName("accept"), + hasParameter(0, hasType(isInteger())), + hasParameter(1, SockAddrPointerType), + hasParameter(2, SockLenPointerType))); +} + +void CloexecAcceptCheck::check(const MatchFinder::MatchResult &Result) { + const std::string &ReplacementText = + (Twine("accept4(") + getSpellingArg(Result, 0) + ", " + + getSpellingArg(Result, 1) + ", " + getSpellingArg(Result, 2) + + ", SOCK_CLOEXEC)") + .str(); + + replaceFunc( + Result, + "prefer accept4() to accept() because accept4() allows SOCK_CLOEXEC", + ReplacementText); +} + +} // namespace android +} // namespace tidy +} // namespace clang Added: clang-tools-extra/trunk/clang-tidy/android/CloexecAcceptCheck.h URL: http://llvm.org/viewvc/llvm-project/clang-tools-extra/trunk/clang-tidy/android/CloexecAcceptCheck.h?rev=311024&view=auto ============================================================================== --- clang-tools-extra/trunk/clang-tidy/android/CloexecAcceptCheck.h (added) +++ clang-tools-extra/trunk/clang-tidy/android/CloexecAcceptCheck.h Wed Aug 16 10:18:16 2017 @@ -0,0 +1,35 @@ +//===--- CloexecAcceptCheck.h - clang-tidy-----------------------*- C++ -*-===// +// +// The LLVM Compiler Infrastructure +// +// This file is distributed under the University of Illinois Open Source +// License. See LICENSE.TXT for details. +// +//===----------------------------------------------------------------------===// + +#ifndef LLVM_CLANG_TOOLS_EXTRA_CLANG_TIDY_ANDROID_CLOEXEC_ACCEPT_H +#define LLVM_CLANG_TOOLS_EXTRA_CLANG_TIDY_ANDROID_CLOEXEC_ACCEPT_H + +#include "CloexecCheck.h" + +namespace clang { +namespace tidy { +namespace android { + +/// accept() is better to be replaced by accept4(). +/// +/// For the user-facing documentation see: +/// http://clang.llvm.org/extra/clang-tidy/checks/android-cloexec-accept.html +class CloexecAcceptCheck : public CloexecCheck { +public: + CloexecAcceptCheck(StringRef Name, ClangTidyContext *Context) + : CloexecCheck(Name, Context) {} + void registerMatchers(ast_matchers::MatchFinder *Finder) override; + void check(const ast_matchers::MatchFinder::MatchResult &Result) override; +}; + +} // namespace android +} // namespace tidy +} // namespace clang + +#endif // LLVM_CLANG_TOOLS_EXTRA_CLANG_TIDY_ANDROID_CLOEXEC_ACCEPT_H Modified: clang-tools-extra/trunk/docs/ReleaseNotes.rst URL: http://llvm.org/viewvc/llvm-project/clang-tools-extra/trunk/docs/ReleaseNotes.rst?rev=311024&r1=311023&r2=311024&view=diff ============================================================================== --- clang-tools-extra/trunk/docs/ReleaseNotes.rst (original) +++ clang-tools-extra/trunk/docs/ReleaseNotes.rst Wed Aug 16 10:18:16 2017 @@ -70,6 +70,11 @@ Improvements to clang-tidy ``AllowConditionalIntegerCasts`` -> ``AllowIntegerConditions``, ``AllowConditionalPointerCasts`` -> ``AllowPointerConditions``. +- New `android-cloexec-accept + <http://clang.llvm.org/extra/clang-tidy/checks/android-cloexec-accept.html>`_ check + + Detects usage of ``accept()``. + - New `android-cloexec-dup <http://clang.llvm.org/extra/clang-tidy/checks/android-cloexec-dup.html>`_ check Added: clang-tools-extra/trunk/docs/clang-tidy/checks/android-cloexec-accept.rst URL: http://llvm.org/viewvc/llvm-project/clang-tools-extra/trunk/docs/clang-tidy/checks/android-cloexec-accept.rst?rev=311024&view=auto ============================================================================== --- clang-tools-extra/trunk/docs/clang-tidy/checks/android-cloexec-accept.rst (added) +++ clang-tools-extra/trunk/docs/clang-tidy/checks/android-cloexec-accept.rst Wed Aug 16 10:18:16 2017 @@ -0,0 +1,18 @@ +.. title:: clang-tidy - android-cloexec-accept + +android-cloexec-accept +====================== + +The usage of ``accept()`` is not recommended, it's better to use ``accept4()``. +Without this flag, an opened sensitive file descriptor would remain open across +a fork+exec to a lower-privileged SELinux domain. + +Examples: + +.. code-block:: c++ + + accept(sockfd, addr, addrlen); + + // becomes + + accept4(sockfd, addr, addrlen, SOCK_CLOEXEC); Modified: clang-tools-extra/trunk/docs/clang-tidy/checks/list.rst URL: http://llvm.org/viewvc/llvm-project/clang-tools-extra/trunk/docs/clang-tidy/checks/list.rst?rev=311024&r1=311023&r2=311024&view=diff ============================================================================== --- clang-tools-extra/trunk/docs/clang-tidy/checks/list.rst (original) +++ clang-tools-extra/trunk/docs/clang-tidy/checks/list.rst Wed Aug 16 10:18:16 2017 @@ -4,6 +4,7 @@ Clang-Tidy Checks ================= .. toctree:: + android-cloexec-accept android-cloexec-creat android-cloexec-dup android-cloexec-fopen Added: clang-tools-extra/trunk/test/clang-tidy/android-cloexec-accept.cpp URL: http://llvm.org/viewvc/llvm-project/clang-tools-extra/trunk/test/clang-tidy/android-cloexec-accept.cpp?rev=311024&view=auto ============================================================================== --- clang-tools-extra/trunk/test/clang-tidy/android-cloexec-accept.cpp (added) +++ clang-tools-extra/trunk/test/clang-tidy/android-cloexec-accept.cpp Wed Aug 16 10:18:16 2017 @@ -0,0 +1,28 @@ +// RUN: %check_clang_tidy %s android-cloexec-accept %t + +struct sockaddr {}; +typedef int socklen_t; +#define NULL 0 + +extern "C" int accept(int sockfd, struct sockaddr *addr, socklen_t *addrlen); + +void f() { + accept(0, NULL, NULL); + // CHECK-MESSAGES: :[[@LINE-1]]:3: warning: prefer accept4() to accept() because accept4() allows SOCK_CLOEXEC [android-cloexec-accept] + // CHECK-FIXES: accept4(0, NULL, NULL, SOCK_CLOEXEC); +} + +namespace i { +int accept(int sockfd, struct sockaddr *addr, socklen_t *addrlen); +void g() { + accept(0, NULL, NULL); +} +} // namespace i + +class C { +public: + int accept(int sockfd, struct sockaddr *addr, socklen_t *addrlen); + void h() { + accept(0, NULL, NULL); + } +}; _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org http://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
