diff --git a/clang/lib/StaticAnalyzer/Checkers/StdLibraryFunctionsChecker.cpp b/clang/lib/StaticAnalyzer/Checkers/StdLibraryFunctionsChecker.cpp --- a/clang/lib/StaticAnalyzer/Checkers/StdLibraryFunctionsChecker.cpp +++ b/clang/lib/StaticAnalyzer/Checkers/StdLibraryFunctionsChecker.cpp @@ -1527,14 +1527,18 @@ const RangeInt UCharRangeMax = std::min(BVF.getMaxValue(ACtx.UnsignedCharTy).getLimitedValue(), IntMax); - // The platform dependent value of EOF. - // Try our best to parse this from the Preprocessor, otherwise fallback to -1. - const auto EOFv = [&C]() -> RangeInt { + // Get platform dependent values of some macros. + // Try our best to parse this from the Preprocessor, otherwise fallback to a + // default value (what is found in a library header). + auto GetMacroValue = [&C](const char *Name, int Default) -> RangeInt { if (const std::optional OptInt = - tryExpandAsInteger("EOF", C.getPreprocessor())) + tryExpandAsInteger(Name, C.getPreprocessor())) return *OptInt; - return -1; - }(); + return Default; + }; + + const auto EOFv = GetMacroValue("EOF", -1); + const auto AT_FDCWDv = GetMacroValue("AT_FDCWD", -100); // Auxiliary class to aid adding summaries to the summary map. struct AddToFunctionSummaryMap { @@ -1979,6 +1983,11 @@ ConstraintSet{ReturnValueCondition(WithinRange, Range(-1, IntMax))}; const auto &ReturnsValidFileDescriptor = ReturnsNonnegative; + auto ValidFileDescriptorOrAtFdcwd = [&](ArgNo ArgN) { + return std::make_shared( + ArgN, WithinRange, Range({AT_FDCWDv, AT_FDCWDv}, {0, IntMax}), ""); + }; + // FILE *fopen(const char *restrict pathname, const char *restrict mode); addToFunctionSummaryMap( "fopen", @@ -2130,6 +2139,7 @@ Summary(NoEvalCall) .Case(ReturnsZero, ErrnoMustNotBeChecked) .Case(ReturnsMinusOne, ErrnoNEZeroIrrelevant) + .ArgConstraint(ValidFileDescriptorOrAtFdcwd(ArgNo(0))) .ArgConstraint(NotNull(ArgNo(1)))); // int dup(int fildes); @@ -2207,7 +2217,7 @@ .Case(ReturnsZero, ErrnoMustNotBeChecked) .Case(ReturnsMinusOne, ErrnoNEZeroIrrelevant) .ArgConstraint(NotNull(ArgNo(0))) - .ArgConstraint(ArgumentCondition(1, WithinRange, Range(0, IntMax))) + .ArgConstraint(ValidFileDescriptorOrAtFdcwd(ArgNo(1))) .ArgConstraint(NotNull(ArgNo(2)))); // int lockf(int fd, int cmd, off_t len); @@ -2318,6 +2328,7 @@ Summary(NoEvalCall) .Case(ReturnsZero, ErrnoMustNotBeChecked) .Case(ReturnsMinusOne, ErrnoNEZeroIrrelevant) + .ArgConstraint(ValidFileDescriptorOrAtFdcwd(ArgNo(0))) .ArgConstraint(NotNull(ArgNo(1)))); std::optional Dev_tTy = lookupTy("dev_t"); @@ -2339,6 +2350,7 @@ Summary(NoEvalCall) .Case(ReturnsZero, ErrnoMustNotBeChecked) .Case(ReturnsMinusOne, ErrnoNEZeroIrrelevant) + .ArgConstraint(ValidFileDescriptorOrAtFdcwd(ArgNo(0))) .ArgConstraint(NotNull(ArgNo(1)))); // int chmod(const char *path, mode_t mode); @@ -2357,7 +2369,7 @@ Summary(NoEvalCall) .Case(ReturnsZero, ErrnoMustNotBeChecked) .Case(ReturnsMinusOne, ErrnoNEZeroIrrelevant) - .ArgConstraint(ArgumentCondition(0, WithinRange, Range(0, IntMax))) + .ArgConstraint(ValidFileDescriptorOrAtFdcwd(ArgNo(0))) .ArgConstraint(NotNull(ArgNo(1)))); // int fchmod(int fildes, mode_t mode); @@ -2381,7 +2393,7 @@ Summary(NoEvalCall) .Case(ReturnsZero, ErrnoMustNotBeChecked) .Case(ReturnsMinusOne, ErrnoNEZeroIrrelevant) - .ArgConstraint(ArgumentCondition(0, WithinRange, Range(0, IntMax))) + .ArgConstraint(ValidFileDescriptorOrAtFdcwd(ArgNo(0))) .ArgConstraint(NotNull(ArgNo(1)))); // int chown(const char *path, uid_t owner, gid_t group); @@ -2446,9 +2458,9 @@ Summary(NoEvalCall) .Case(ReturnsZero, ErrnoMustNotBeChecked) .Case(ReturnsMinusOne, ErrnoNEZeroIrrelevant) - .ArgConstraint(ArgumentCondition(0, WithinRange, Range(0, IntMax))) + .ArgConstraint(ValidFileDescriptorOrAtFdcwd(ArgNo(0))) .ArgConstraint(NotNull(ArgNo(1))) - .ArgConstraint(ArgumentCondition(2, WithinRange, Range(0, IntMax))) + .ArgConstraint(ValidFileDescriptorOrAtFdcwd(ArgNo(2))) .ArgConstraint(NotNull(ArgNo(3)))); // int unlink(const char *pathname); @@ -2466,7 +2478,7 @@ Summary(NoEvalCall) .Case(ReturnsZero, ErrnoMustNotBeChecked) .Case(ReturnsMinusOne, ErrnoNEZeroIrrelevant) - .ArgConstraint(ArgumentCondition(0, WithinRange, Range(0, IntMax))) + .ArgConstraint(ValidFileDescriptorOrAtFdcwd(ArgNo(0))) .ArgConstraint(NotNull(ArgNo(1)))); std::optional StructStatTy = lookupTy("stat"); @@ -2515,7 +2527,7 @@ Summary(NoEvalCall) .Case(ReturnsZero, ErrnoMustNotBeChecked) .Case(ReturnsMinusOne, ErrnoNEZeroIrrelevant) - .ArgConstraint(ArgumentCondition(0, WithinRange, Range(0, IntMax))) + .ArgConstraint(ValidFileDescriptorOrAtFdcwd(ArgNo(0))) .ArgConstraint(NotNull(ArgNo(1))) .ArgConstraint(NotNull(ArgNo(2)))); @@ -2690,7 +2702,7 @@ ReturnValueCondition(WithinRange, Range(0, Ssize_tMax))}, ErrnoMustNotBeChecked) .Case(ReturnsMinusOne, ErrnoNEZeroIrrelevant) - .ArgConstraint(ArgumentCondition(0, WithinRange, Range(0, IntMax))) + .ArgConstraint(ValidFileDescriptorOrAtFdcwd(ArgNo(0))) .ArgConstraint(NotNull(ArgNo(1))) .ArgConstraint(NotNull(ArgNo(2))) .ArgConstraint(BufferSize(/*Buffer=*/ArgNo(2), @@ -2707,7 +2719,9 @@ Summary(NoEvalCall) .Case(ReturnsZero, ErrnoMustNotBeChecked) .Case(ReturnsMinusOne, ErrnoNEZeroIrrelevant) + .ArgConstraint(ValidFileDescriptorOrAtFdcwd(ArgNo(0))) .ArgConstraint(NotNull(ArgNo(1))) + .ArgConstraint(ValidFileDescriptorOrAtFdcwd(ArgNo(2))) .ArgConstraint(NotNull(ArgNo(3)))); // char *realpath(const char *restrict file_name, diff --git a/clang/test/Analysis/std-c-library-functions-arg-constraints.c b/clang/test/Analysis/std-c-library-functions-arg-constraints.c --- a/clang/test/Analysis/std-c-library-functions-arg-constraints.c +++ b/clang/test/Analysis/std-c-library-functions-arg-constraints.c @@ -3,6 +3,7 @@ // RUN: -analyzer-checker=core \ // RUN: -analyzer-checker=apiModeling.StdCLibraryFunctions \ // RUN: -analyzer-checker=alpha.unix.StdCLibraryFunctionArgs \ +// RUN: -analyzer-config apiModeling.StdCLibraryFunctions:ModelPOSIX=true \ // RUN: -analyzer-checker=debug.StdCLibraryFunctionsTester \ // RUN: -analyzer-checker=debug.ExprInspection \ // RUN: -triple x86_64-unknown-linux-gnu \ @@ -13,6 +14,7 @@ // RUN: -analyzer-checker=core \ // RUN: -analyzer-checker=apiModeling.StdCLibraryFunctions \ // RUN: -analyzer-checker=alpha.unix.StdCLibraryFunctionArgs \ +// RUN: -analyzer-config apiModeling.StdCLibraryFunctions:ModelPOSIX=true \ // RUN: -analyzer-checker=debug.StdCLibraryFunctionsTester \ // RUN: -analyzer-checker=debug.ExprInspection \ // RUN: -triple x86_64-unknown-linux-gnu \ @@ -309,3 +311,26 @@ // bugpath-warning{{The 1st argument to '__buf_size_arg_constraint_concrete' is out of the accepted range; It should be a buffer with size equal to or greater than 10}} \ // bugpath-note{{The 1st argument to '__buf_size_arg_constraint_concrete' is out of the accepted range; It should be a buffer with size equal to or greater than 10}} } + +void test_file_fd_at_functions() { + (void)linkat(-22, "from", AT_FDCWD, "to", 0); // \ + // report-warning{{The 1st argument to 'linkat' is -22 but should be -101 or >= 0}} \ + // bugpath-warning{{The 1st argument to 'linkat' is -22 but should be -101 or >= 0}} \ + // bugpath-note{{The 1st argument to 'linkat' is -22 but should be -101 or >= 0}} + + // no warning for these functions if the AT_FDCWD value is used + (void)linkat(AT_FDCWD, "from", AT_FDCWD, "to", 0); + (void)faccessat(AT_FDCWD, "path", 0, 0); + (void)symlinkat("oldpath", AT_FDCWD, "newpath"); + (void)mkdirat(AT_FDCWD, "path", 0); + (void)mknodat(AT_FDCWD, "path", 0, 0); + (void)fchmodat(AT_FDCWD, "path", 0, 0); + (void)fchownat(AT_FDCWD, "path", 0, 0, 0); + (void)linkat(AT_FDCWD, "oldpath", AT_FDCWD, "newpath", 0); + (void)unlinkat(AT_FDCWD, "newpath", 0); + struct stat St; + (void)fstatat(AT_FDCWD, "newpath", &St, 0); + char Buf[10]; + (void)readlinkat(AT_FDCWD, "newpath", Buf, 10); + (void)renameat(AT_FDCWD, "oldpath", AT_FDCWD, "newpath"); +}