llvmbot wrote:
<!--LLVM PR SUMMARY COMMENT--> @llvm/pr-subscribers-clang @llvm/pr-subscribers-clang-static-analyzer-1 Author: Balázs Kéri (balazske) <details> <summary>Changes</summary> The functions 'readlink' and 'readlinkat' do return 0 only if the 'bufsize' argument is 0. --- Full diff: https://github.com/llvm/llvm-project/pull/71373.diff 2 Files Affected: - (modified) clang/lib/StaticAnalyzer/Checkers/StdLibraryFunctionsChecker.cpp (+14-4) - (modified) clang/test/Analysis/std-c-library-functions-POSIX.c (+20) ``````````diff diff --git a/clang/lib/StaticAnalyzer/Checkers/StdLibraryFunctionsChecker.cpp b/clang/lib/StaticAnalyzer/Checkers/StdLibraryFunctionsChecker.cpp index 13bb9cef5e490ed..54a41b8bd7843dd 100644 --- a/clang/lib/StaticAnalyzer/Checkers/StdLibraryFunctionsChecker.cpp +++ b/clang/lib/StaticAnalyzer/Checkers/StdLibraryFunctionsChecker.cpp @@ -2865,9 +2865,14 @@ void StdLibraryFunctionsChecker::initFunctionSummaries( Signature(ArgTypes{ConstCharPtrRestrictTy, CharPtrRestrictTy, SizeTy}, RetType{Ssize_tTy}), Summary(NoEvalCall) - .Case({ReturnValueCondition(LessThanOrEq, ArgNo(2)), - ReturnValueCondition(WithinRange, Range(0, Ssize_tMax))}, + .Case({ArgumentCondition(2, WithinRange, Range(1, IntMax)), + ReturnValueCondition(LessThanOrEq, ArgNo(2)), + ReturnValueCondition(WithinRange, Range(1, Ssize_tMax))}, ErrnoMustNotBeChecked, GenericSuccessMsg) + .Case({ArgumentCondition(2, WithinRange, SingleValue(0)), + ReturnValueCondition(WithinRange, SingleValue(0))}, + ErrnoMustNotBeChecked, + "Assuming that argument 'bufsize' is 0") .Case(ReturnsMinusOne, ErrnoNEZeroIrrelevant, GenericFailureMsg) .ArgConstraint(NotNull(ArgNo(0))) .ArgConstraint(NotNull(ArgNo(1))) @@ -2884,9 +2889,14 @@ void StdLibraryFunctionsChecker::initFunctionSummaries( ArgTypes{IntTy, ConstCharPtrRestrictTy, CharPtrRestrictTy, SizeTy}, RetType{Ssize_tTy}), Summary(NoEvalCall) - .Case({ReturnValueCondition(LessThanOrEq, ArgNo(3)), - ReturnValueCondition(WithinRange, Range(0, Ssize_tMax))}, + .Case({ArgumentCondition(3, WithinRange, Range(1, IntMax)), + ReturnValueCondition(LessThanOrEq, ArgNo(3)), + ReturnValueCondition(WithinRange, Range(1, Ssize_tMax))}, ErrnoMustNotBeChecked, GenericSuccessMsg) + .Case({ArgumentCondition(3, WithinRange, SingleValue(0)), + ReturnValueCondition(WithinRange, SingleValue(0))}, + ErrnoMustNotBeChecked, + "Assuming that argument 'bufsize' is 0") .Case(ReturnsMinusOne, ErrnoNEZeroIrrelevant, GenericFailureMsg) .ArgConstraint(ValidFileDescriptorOrAtFdcwd(ArgNo(0))) .ArgConstraint(NotNull(ArgNo(1))) diff --git a/clang/test/Analysis/std-c-library-functions-POSIX.c b/clang/test/Analysis/std-c-library-functions-POSIX.c index 84ce0f21e569fb5..daa4d904c3ac5ed 100644 --- a/clang/test/Analysis/std-c-library-functions-POSIX.c +++ b/clang/test/Analysis/std-c-library-functions-POSIX.c @@ -205,3 +205,23 @@ void test_sendmsg(int sockfd, const struct msghdr *msg, int flags) { ssize_t Ret = sendmsg(sockfd, msg, flags); clang_analyzer_eval(Ret != 0); // expected-warning{{TRUE}} } + +void test_readlink_bufsize_zero(char *Buf, size_t Bufsize) { + ssize_t Ret = readlink("path", Buf, Bufsize); + if (Ret == 0) + clang_analyzer_eval(Bufsize == 0); // expected-warning{{TRUE}} + else if (Ret > 0) + clang_analyzer_eval(Bufsize == 0); // expected-warning{{FALSE}} + else + clang_analyzer_eval(Bufsize == 0); // expected-warning{{UNKNOWN}} +} + +void test_readlinkat_bufsize_zero(int fd, char *Buf, size_t Bufsize) { + ssize_t Ret = readlinkat(fd, "path", Buf, Bufsize); + if (Ret == 0) + clang_analyzer_eval(Bufsize == 0); // expected-warning{{TRUE}} + else if (Ret > 0) + clang_analyzer_eval(Bufsize == 0); // expected-warning{{FALSE}} + else + clang_analyzer_eval(Bufsize == 0); // expected-warning{{UNKNOWN}} +} `````````` </details> https://github.com/llvm/llvm-project/pull/71373 _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
