Index: clang/include/clang/AST/Decl.h =================================================================== --- clang/include/clang/AST/Decl.h +++ clang/include/clang/AST/Decl.h @@ -2255,7 +2255,7 @@ return const_cast(this)->getCanonicalDecl(); } - unsigned getBuiltinID() const; + unsigned getBuiltinID(bool ConsiderWrapperFunctions = false) const; // ArrayRef interface to parameters. ArrayRef parameters() const { Index: clang/include/clang/Basic/DiagnosticGroups.td =================================================================== --- clang/include/clang/Basic/DiagnosticGroups.td +++ clang/include/clang/Basic/DiagnosticGroups.td @@ -1052,3 +1052,5 @@ def CrossTU : DiagGroup<"ctu">; def CTADMaybeUnsupported : DiagGroup<"ctad-maybe-unsupported">; + +def FortifySource : DiagGroup<"fortify-source">; Index: clang/include/clang/Basic/DiagnosticSemaKinds.td =================================================================== --- clang/include/clang/Basic/DiagnosticSemaKinds.td +++ clang/include/clang/Basic/DiagnosticSemaKinds.td @@ -677,6 +677,12 @@ " but size argument is %2">, InGroup>; +def warn_fortify_source_overflow + : Warning, InGroup; +def warn_fortify_source_size_mismatch : Warning< + "'%0' size argument is too large; destination buffer has size %1," + " but size argument is %2">, InGroup; + /// main() // static main() is not an error in C, just in C++. def warn_static_main : Warning<"'main' should not be declared static">, Index: clang/include/clang/Sema/Sema.h =================================================================== --- clang/include/clang/Sema/Sema.h +++ clang/include/clang/Sema/Sema.h @@ -10665,6 +10665,7 @@ ExprResult CheckBuiltinFunctionCall(FunctionDecl *FDecl, unsigned BuiltinID, CallExpr *TheCall); + void checkFortifiedBuiltinMemoryFunction(FunctionDecl *FD, CallExpr *TheCall); bool CheckARMBuiltinExclusiveCall(unsigned BuiltinID, CallExpr *TheCall, unsigned MaxWidth); Index: clang/lib/AST/Decl.cpp =================================================================== --- clang/lib/AST/Decl.cpp +++ clang/lib/AST/Decl.cpp @@ -2981,16 +2981,20 @@ FunctionDecl *FunctionDecl::getCanonicalDecl() { return getFirstDecl(); } -/// Returns a value indicating whether this function -/// corresponds to a builtin function. +/// Returns a value indicating whether this function corresponds to a builtin +/// function. /// -/// The function corresponds to a built-in function if it is -/// declared at translation scope or within an extern "C" block and -/// its name matches with the name of a builtin. The returned value -/// will be 0 for functions that do not correspond to a builtin, a -/// value of type \c Builtin::ID if in the target-independent range -/// \c [1,Builtin::First), or a target-specific builtin value. -unsigned FunctionDecl::getBuiltinID() const { +/// The function corresponds to a built-in function if it is declared at +/// translation scope or within an extern "C" block and its name matches with +/// the name of a builtin. The returned value will be 0 for functions that do +/// not correspond to a builtin, a value of type \c Builtin::ID if in the +/// target-independent range \c [1,Builtin::First), or a target-specific builtin +/// value. +/// +/// \param ConsiderWrapperFunctions If we should consider wrapper functions as +/// their wrapped builtins. This shouldn't be done in general, but its useful in +/// Sema to diagnose calls to wrappers based on their semantics. +unsigned FunctionDecl::getBuiltinID(bool ConsiderWrapperFunctions) const { if (!getIdentifier()) return 0; @@ -3018,7 +3022,7 @@ // If the function is marked "overloadable", it has a different mangled name // and is not the C library function. - if (hasAttr()) + if (!ConsiderWrapperFunctions && hasAttr()) return 0; if (!Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) @@ -3029,7 +3033,7 @@ // function or whether it just has the same name. // If this is a static function, it's not a builtin. - if (getStorageClass() == SC_Static) + if (!ConsiderWrapperFunctions && getStorageClass() == SC_Static) return 0; // OpenCL v1.2 s6.9.f - The library functions defined in Index: clang/lib/Sema/SemaChecking.cpp =================================================================== --- clang/lib/Sema/SemaChecking.cpp +++ clang/lib/Sema/SemaChecking.cpp @@ -235,47 +235,6 @@ return false; } -static void SemaBuiltinMemChkCall(Sema &S, FunctionDecl *FDecl, - CallExpr *TheCall, unsigned SizeIdx, - unsigned DstSizeIdx, - StringRef LikelyMacroName) { - if (TheCall->getNumArgs() <= SizeIdx || - TheCall->getNumArgs() <= DstSizeIdx) - return; - - const Expr *SizeArg = TheCall->getArg(SizeIdx); - const Expr *DstSizeArg = TheCall->getArg(DstSizeIdx); - - Expr::EvalResult SizeResult, DstSizeResult; - - // find out if both sizes are known at compile time - if (!SizeArg->EvaluateAsInt(SizeResult, S.Context) || - !DstSizeArg->EvaluateAsInt(DstSizeResult, S.Context)) - return; - - llvm::APSInt Size = SizeResult.Val.getInt(); - llvm::APSInt DstSize = DstSizeResult.Val.getInt(); - - if (Size.ule(DstSize)) - return; - - // Confirmed overflow, so generate the diagnostic. - StringRef FunctionName = FDecl->getName(); - SourceLocation SL = TheCall->getBeginLoc(); - SourceManager &SM = S.getSourceManager(); - // If we're in an expansion of a macro whose name corresponds to this builtin, - // use the simple macro name and location. - if (SL.isMacroID() && Lexer::getImmediateMacroName(SL, SM, S.getLangOpts()) == - LikelyMacroName) { - FunctionName = LikelyMacroName; - SL = SM.getImmediateMacroCallerLoc(SL); - } - - S.Diag(SL, diag::warn_memcpy_chk_overflow) - << FunctionName << DstSize.toString(/*Radix=*/10) - << Size.toString(/*Radix=*/10); -} - static bool SemaBuiltinCallWithStaticChain(Sema &S, CallExpr *BuiltinCall) { if (checkArgCount(S, BuiltinCall, 2)) return true; @@ -339,6 +298,139 @@ return false; } +/// Check a call to BuiltinID for buffer overflows. If BuiltinID is a +/// __builtin_*_chk function, then use the object size argument specified in the +/// source. Otherwise, infer the object size using __builtin_object_size. +void Sema::checkFortifiedBuiltinMemoryFunction(FunctionDecl *FD, + CallExpr *TheCall) { + // FIXME: There are some more useful checks we could be doing here: + // - Analyze the format string of sprintf to see how much of buffer is used. + // - Evaluate strlen of strcpy arguments, use as object size. + + unsigned BuiltinID = FD->getBuiltinID(/*ConsiderWrappers=*/true); + if (!BuiltinID) + return; + llvm::APSInt UsedSize, ComputedSize; + + // If this is a call to a non-fortified function, then determine what the + // buffer size would be. + auto computeObjectSize = [&](unsigned ObjIdx) { + // If the parameter has a pass_object_size attribute, then we should use + // it's (potentially) more strict checking mode. Otherwise, conservatively + // assume type 0. + int BOSType = 0; + if (auto *POS = FD->getParamDecl(ObjIdx)->getAttr()) + BOSType = POS->getType(); + + Expr *ObjArg = TheCall->getArg(ObjIdx); + uint64_t Result; + if (!ObjArg->tryEvaluateObjectSize(Result, getASTContext(), BOSType)) + return false; + // Get the object size in the target's size_t width. + const TargetInfo &TI = getASTContext().getTargetInfo(); + unsigned SizeTypeWidth = TI.getTypeWidth(TI.getSizeType()); + ComputedSize = llvm::APSInt::getUnsigned(Result).extOrTrunc(SizeTypeWidth); + return true; + }; + + auto evaluateObjectSize = [&](unsigned Idx) { + Expr *SizeArg = TheCall->getArg(Idx); + Expr::EvalResult Result; + if (!SizeArg->EvaluateAsInt(Result, getASTContext())) + return false; + ComputedSize = Result.Val.getInt(); + return true; + }; + + auto evaluateSizeArg = [&](unsigned Idx) { + Expr *SizeArg = TheCall->getArg(Idx); + Expr::EvalResult Result; + if (!SizeArg->EvaluateAsInt(Result, getASTContext())) + return false; + UsedSize = Result.Val.getInt(); + return true; + }; + + unsigned DiagID = 0; + switch (BuiltinID) { + default: return; + case Builtin::BI__builtin___memcpy_chk: + case Builtin::BI__builtin___memmove_chk: + case Builtin::BI__builtin___memset_chk: + case Builtin::BI__builtin___strlcat_chk: + case Builtin::BI__builtin___strlcpy_chk: + case Builtin::BI__builtin___strncat_chk: + case Builtin::BI__builtin___strncpy_chk: + case Builtin::BI__builtin___stpncpy_chk: + case Builtin::BI__builtin___memccpy_chk: { + DiagID = diag::warn_memcpy_chk_overflow; + if (!evaluateObjectSize(TheCall->getNumArgs()-1) || + !evaluateSizeArg(TheCall->getNumArgs()-2)) + return; + break; + } + case Builtin::BI__builtin___snprintf_chk: + case Builtin::BI__builtin___vsnprintf_chk: { + DiagID = diag::warn_memcpy_chk_overflow; + if (!evaluateObjectSize(3) || !evaluateSizeArg(1)) + return; + break; + } + + case Builtin::BIstrncat: + case Builtin::BI__builtin_strncat: + case Builtin::BIstrncpy: + case Builtin::BI__builtin_strncpy: + case Builtin::BIstpncpy: + case Builtin::BI__builtin_stpncpy: { + if (!computeObjectSize(0) || !evaluateSizeArg(TheCall->getNumArgs() - 1)) + return; + // Whether these functions overflow depend on the runtime strlen of the + // string, not just the buffer size, so emitting the "always overflow" + // diagnostic isn't quite right. We should still diagnose passing a buffer + // size larger than the destination buffer though; this is a runtime abort + // in _FORTIFY_SOURCE mode, and is quite suspicious otherwise. + DiagID = diag::warn_fortify_source_size_mismatch; + break; + } + + case Builtin::BImemcpy: + case Builtin::BI__builtin_memcpy: + case Builtin::BImemmove: + case Builtin::BI__builtin_memmove: + case Builtin::BImemset: + case Builtin::BI__builtin_memset: { + if (!computeObjectSize(0) || !evaluateSizeArg(TheCall->getNumArgs() - 1)) + return; + DiagID = diag::warn_fortify_source_overflow; + break; + } + case Builtin::BIsnprintf: + case Builtin::BI__builtin_snprintf: + case Builtin::BIvsnprintf: + case Builtin::BI__builtin_vsnprintf: { + if (!computeObjectSize(0) || !evaluateSizeArg(1)) + return; + DiagID = diag::warn_fortify_source_size_mismatch; + break; + } + } + + if (UsedSize.ule(ComputedSize)) + return; + + StringRef FunctionName = getASTContext().BuiltinInfo.getName(BuiltinID); + if (DiagID == diag::warn_memcpy_chk_overflow) { + // __builtin___memcpy_chk -> memcpy + FunctionName = FunctionName.drop_front(std::strlen("__builtin___")); + FunctionName = FunctionName.drop_back(std::strlen("_chk")); + } + + Diag(TheCall->getBeginLoc(), DiagID) + << FunctionName << ComputedSize.toString(/*Radix=*/10) + << UsedSize.toString(/*Radix=*/10); +} + static bool SemaBuiltinSEHScopeCheck(Sema &SemaRef, CallExpr *TheCall, Scope::ScopeFlags NeededScopeFlags, unsigned DiagID) { @@ -1302,42 +1394,6 @@ TheCall->setType(Context.IntTy); break; } - - // check secure string manipulation functions where overflows - // are detectable at compile time - case Builtin::BI__builtin___memcpy_chk: - SemaBuiltinMemChkCall(*this, FDecl, TheCall, 2, 3, "memcpy"); - break; - case Builtin::BI__builtin___memmove_chk: - SemaBuiltinMemChkCall(*this, FDecl, TheCall, 2, 3, "memmove"); - break; - case Builtin::BI__builtin___memset_chk: - SemaBuiltinMemChkCall(*this, FDecl, TheCall, 2, 3, "memset"); - break; - case Builtin::BI__builtin___strlcat_chk: - SemaBuiltinMemChkCall(*this, FDecl, TheCall, 2, 3, "strlcat"); - break; - case Builtin::BI__builtin___strlcpy_chk: - SemaBuiltinMemChkCall(*this, FDecl, TheCall, 2, 3, "strlcpy"); - break; - case Builtin::BI__builtin___strncat_chk: - SemaBuiltinMemChkCall(*this, FDecl, TheCall, 2, 3, "strncat"); - break; - case Builtin::BI__builtin___strncpy_chk: - SemaBuiltinMemChkCall(*this, FDecl, TheCall, 2, 3, "strncpy"); - break; - case Builtin::BI__builtin___stpncpy_chk: - SemaBuiltinMemChkCall(*this, FDecl, TheCall, 2, 3, "stpncpy"); - break; - case Builtin::BI__builtin___memccpy_chk: - SemaBuiltinMemChkCall(*this, FDecl, TheCall, 3, 4, "memccpy"); - break; - case Builtin::BI__builtin___snprintf_chk: - SemaBuiltinMemChkCall(*this, FDecl, TheCall, 1, 3, "snprintf"); - break; - case Builtin::BI__builtin___vsnprintf_chk: - SemaBuiltinMemChkCall(*this, FDecl, TheCall, 1, 3, "vsnprintf"); - break; case Builtin::BI__builtin_call_with_static_chain: if (SemaBuiltinCallWithStaticChain(*this, TheCall)) return ExprError(); Index: clang/lib/Sema/SemaExpr.cpp =================================================================== --- clang/lib/Sema/SemaExpr.cpp +++ clang/lib/Sema/SemaExpr.cpp @@ -5926,6 +5926,8 @@ if (CheckFunctionCall(FDecl, TheCall, Proto)) return ExprError(); + checkFortifiedBuiltinMemoryFunction(FDecl, TheCall); + if (BuiltinID) return CheckBuiltinFunctionCall(FDecl, BuiltinID, TheCall); } else if (NDecl) { Index: clang/test/Analysis/bstring.c =================================================================== --- clang/test/Analysis/bstring.c +++ clang/test/Analysis/bstring.c @@ -72,7 +72,10 @@ char src[] = {1, 2, 3, 4}; char dst[1]; - memcpy(dst, src, 4); // expected-warning{{Memory copy function overflows destination buffer}} + memcpy(dst, src, 4); // expected-warning{{Memory copy function overflows destination buffer}} +#ifndef VARIANT + // expected-warning@-2{{memcpy' will always overflow; destination buffer has size 1, but size argument is 4}} +#endif } void memcpy3 () { @@ -94,6 +97,9 @@ char dst[3]; memcpy(dst+2, src+2, 2); // expected-warning{{Memory copy function overflows destination buffer}} +#ifndef VARIANT + // expected-warning@-2{{memcpy' will always overflow; destination buffer has size 1, but size argument is 2}} +#endif } void memcpy6() { @@ -351,7 +357,10 @@ char src[] = {1, 2, 3, 4}; char dst[1]; - memmove(dst, src, 4); // expected-warning{{overflow}} + memmove(dst, src, 4); // expected-warning{{Memory copy function overflows destination buffer}} +#ifndef VARIANT + // expected-warning@-2{{memmove' will always overflow; destination buffer has size 1, but size argument is 4}} +#endif } //===----------------------------------------------------------------------=== Index: clang/test/Analysis/null-deref-ps-region.c =================================================================== --- clang/test/Analysis/null-deref-ps-region.c +++ clang/test/Analysis/null-deref-ps-region.c @@ -51,7 +51,7 @@ void testStackArrayOutOfBound() { char buf[1]; - memset(buf, 0, 1024); // expected-warning {{Memory set function accesses out-of-bound array element}} + memset(buf, 0, 1024); // expected-warning {{Memory set function accesses out-of-bound array element}} expected-warning {{'memset' will always overflow; destination buffer has size 1, but size argument is 1024}} } void testHeapSymbolOutOfBound() { Index: clang/test/Analysis/pr22954.c =================================================================== --- clang/test/Analysis/pr22954.c +++ clang/test/Analysis/pr22954.c @@ -303,7 +303,7 @@ i18.j = 11; i18.s2 = strdup("hello"); char input[100] = {3}; - memcpy(i18.s1, input, 100); + memcpy(i18.s1, input, 100); // expected-warning {{'memcpy' will always overflow; destination buffer has size 24, but size argument is 100}} clang_analyzer_eval(i18.s1[0] == 1); // expected-warning{{UNKNOWN}}\ expected-warning{{Potential leak of memory pointed to by 'i18.s2'}} clang_analyzer_eval(i18.s1[1] == 2); // expected-warning{{UNKNOWN}} @@ -534,7 +534,7 @@ struct aa a262 = {{1, 2, 3, 4}, 0}; a262.s2 = strdup("hello"); char input[] = {'a', 'b', 'c', 'd'}; - memcpy(a262.s1, input, -1); + memcpy(a262.s1, input, -1); // expected-warning{{'memcpy' will always overflow; destination buffer has size 16, but size argument is 18446744073709551615}} clang_analyzer_eval(a262.s1[0] == 1); // expected-warning{{UNKNOWN}}\ expected-warning{{Potential leak of memory pointed to by 'a262.s2'}} clang_analyzer_eval(a262.s1[1] == 1); // expected-warning{{UNKNOWN}} Index: clang/test/Analysis/string.c =================================================================== --- clang/test/Analysis/string.c +++ clang/test/Analysis/string.c @@ -517,12 +517,18 @@ char x[4]; if (strlen(y) == 4) strncpy(x, y, 5); // expected-warning{{Size argument is greater than the length of the destination buffer}} +#ifndef VARIANT + // expected-warning@-2{{size argument is too large; destination buffer has size 4, but size argument is 5}} +#endif } void strncpy_no_overflow(char *y) { char x[4]; if (strlen(y) == 3) strncpy(x, y, 5); // expected-warning{{Size argument is greater than the length of the destination buffer}} +#ifndef VARIANT + // expected-warning@-2{{size argument is too large; destination buffer has size 4, but size argument is 5}} +#endif } void strncpy_no_overflow2(char *y, int n) { @@ -1247,7 +1253,7 @@ void memset8_char_array_nonnull() { char str[5] = "abcd"; clang_analyzer_eval(strlen(str) == 4); // expected-warning{{TRUE}} - memset(str, '0', 10); + memset(str, '0', 10); // expected-warning{{'memset' will always overflow; destination buffer has size 5, but size argument is 10}} clang_analyzer_eval(str[0] != '0'); // expected-warning{{UNKNOWN}} clang_analyzer_eval(strlen(str) >= 10); // expected-warning{{TRUE}} clang_analyzer_eval(strlen(str) < 10); // expected-warning{{FALSE}} @@ -1284,7 +1290,7 @@ struct POD_memset pod; pod.num = 1; pod.c = '1'; - memset(&pod.c, 0, sizeof(struct POD_memset)); + memset(&pod.c, 0, sizeof(struct POD_memset)); // expected-warning {{'memset' will always overflow; destination buffer has size 4, but size argument is 8}} clang_analyzer_eval(pod.num == 0); // expected-warning{{UNKNOWN}} clang_analyzer_eval(pod.c == 0); // expected-warning{{UNKNOWN}} } Index: clang/test/Sema/builtin-object-size.c =================================================================== --- clang/test/Sema/builtin-object-size.c +++ clang/test/Sema/builtin-object-size.c @@ -30,7 +30,7 @@ // rdar://6252231 - cannot call vsnprintf with va_list on x86_64 void f4(const char *fmt, ...) { __builtin_va_list args; - __builtin___vsnprintf_chk (0, 42, 0, 11, fmt, args); // expected-warning {{'__builtin___vsnprintf_chk' will always overflow; destination buffer has size 11, but size argument is 42}} + __builtin___vsnprintf_chk (0, 42, 0, 11, fmt, args); // expected-warning {{'vsnprintf' will always overflow; destination buffer has size 11, but size argument is 42}} } // rdar://18334276 @@ -57,7 +57,7 @@ char b[5]; char buf[10]; __builtin___memccpy_chk (buf, b, '\0', sizeof(b), OBJECT_SIZE_BUILTIN (buf, 0)); - __builtin___memccpy_chk (b, buf, '\0', sizeof(buf), OBJECT_SIZE_BUILTIN (b, 0)); // expected-warning {{'__builtin___memccpy_chk' will always overflow; destination buffer has size 5, but size argument is 10}} + __builtin___memccpy_chk (b, buf, '\0', sizeof(buf), OBJECT_SIZE_BUILTIN (b, 0)); // expected-warning {{'memccpy' will always overflow; destination buffer has size 5, but size argument is 10}} } int pr28314(void) { Index: clang/test/Sema/builtins.c =================================================================== --- clang/test/Sema/builtins.c +++ clang/test/Sema/builtins.c @@ -230,14 +230,14 @@ // expected-note {{change size argument to be the size of the destination}} __builtin___strlcpy_chk(buf, b, sizeof(b), __builtin_object_size(buf, 0)); // expected-warning {{size argument in '__builtin___strlcpy_chk' call appears to be size of the source; expected the size of the destination}} \ // expected-note {{change size argument to be the size of the destination}} \ - // expected-warning {{'__builtin___strlcpy_chk' will always overflow; destination buffer has size 20, but size argument is 40}} + // expected-warning {{'strlcpy' will always overflow; destination buffer has size 20, but size argument is 40}} strlcat(buf, b, sizeof(b)); // expected-warning {{size argument in 'strlcat' call appears to be size of the source; expected the size of the destination}} \ // expected-note {{change size argument to be the size of the destination}} __builtin___strlcat_chk(buf, b, sizeof(b), __builtin_object_size(buf, 0)); // expected-warning {{size argument in '__builtin___strlcat_chk' call appears to be size of the source; expected the size of the destination}} \ // expected-note {{change size argument to be the size of the destination}} \ - // expected-warning {{'__builtin___strlcat_chk' will always overflow; destination buffer has size 20, but size argument is 40}} + // expected-warning {{'strlcat' will always overflow; destination buffer has size 20, but size argument is 40}} } // rdar://11076881 @@ -245,7 +245,7 @@ { static char buf[10]; - __builtin___memcpy_chk (&buf[6], in, 5, __builtin_object_size (&buf[6], 0)); // expected-warning {{'__builtin___memcpy_chk' will always overflow; destination buffer has size 4, but size argument is 5}} + __builtin___memcpy_chk (&buf[6], in, 5, __builtin_object_size (&buf[6], 0)); // expected-warning {{'memcpy' will always overflow; destination buffer has size 4, but size argument is 5}} __builtin___memcpy_chk (p, "abcde", n, __builtin_object_size (p, 0)); @@ -253,7 +253,7 @@ __builtin___memcpy_chk (&buf[5], "abcde", n, __builtin_object_size (&buf[5], 0)); - __builtin___memcpy_chk (&buf[6], "abcde", 5, __builtin_object_size (&buf[6], 0)); // expected-warning {{'__builtin___memcpy_chk' will always overflow; destination buffer has size 4, but size argument is 5}} + __builtin___memcpy_chk (&buf[6], "abcde", 5, __builtin_object_size (&buf[6], 0)); // expected-warning {{'memcpy' will always overflow; destination buffer has size 4, but size argument is 5}} return buf; } @@ -312,5 +312,5 @@ char src[1024]; char buf[10]; memcpy(buf, src, 11); // expected-warning{{'memcpy' will always overflow; destination buffer has size 10, but size argument is 11}} - my_memcpy(buf, src, 11); // expected-warning{{'__builtin___memcpy_chk' will always overflow; destination buffer has size 10, but size argument is 11}} + my_memcpy(buf, src, 11); // expected-warning{{'memcpy' will always overflow; destination buffer has size 10, but size argument is 11}} } Index: clang/test/Sema/transpose-memset.c =================================================================== --- clang/test/Sema/transpose-memset.c +++ clang/test/Sema/transpose-memset.c @@ -10,7 +10,7 @@ int main() { memset(array, sizeof(array), 0); // expected-warning{{'size' argument to memset is '0'; did you mean to transpose the last two arguments?}} expected-note{{parenthesize the third argument to silence}} - memset(array, sizeof(array), 0xff); // expected-warning{{setting buffer to a 'sizeof' expression; did you mean to transpose the last two arguments?}} expected-note{{cast the second argument to 'int' to silence}} + memset(array, sizeof(array), 0xff); // expected-warning{{setting buffer to a 'sizeof' expression; did you mean to transpose the last two arguments?}} expected-note{{cast the second argument to 'int' to silence}} expected-warning{{'__builtin_memset' will always overflow; destination buffer has size 40, but size argument is 255}} memset(ptr, sizeof(ptr), 0); // expected-warning{{'size' argument to memset is '0'; did you mean to transpose the last two arguments?}} expected-note{{parenthesize the third argument to silence}} memset(ptr, sizeof(*ptr) * 10, 1); // expected-warning{{setting buffer to a 'sizeof' expression; did you mean to transpose the last two arguments?}} expected-note{{cast the second argument to 'int' to silence}} memset(ptr, 10 * sizeof(int *), 1); // expected-warning{{setting buffer to a 'sizeof' expression; did you mean to transpose the last two arguments?}} expected-note{{cast the second argument to 'int' to silence}} Index: clang/test/Sema/warn-fortify-source.c =================================================================== --- /dev/null +++ clang/test/Sema/warn-fortify-source.c @@ -0,0 +1,83 @@ +// RUN: %clang_cc1 -triple x86_64-apple-macosx10.14.0 %s -verify +// RUN: %clang_cc1 -triple x86_64-apple-macosx10.14.0 %s -verify -DUSE_PASS_OBJECT_SIZE +// RUN: %clang_cc1 -triple x86_64-apple-macosx10.14.0 %s -verify -DUSE_BUILTINS + +typedef unsigned long size_t; + +#if defined(USE_PASS_OBJECT_SIZE) +void *memcpy(void *dst, const void *src, size_t c); +static void *memcpy(void *dst __attribute__((pass_object_size(1))), const void *src, size_t c) __attribute__((overloadable)) __asm__("merp"); +static void *memcpy(void *const dst __attribute__((pass_object_size(1))), const void *src, size_t c) __attribute__((overloadable)) { + return 0; +} +#elif defined(USE_BUILTINS) +#define memcpy(x,y,z) __builtin_memcpy(x,y,z) +#else +void *memcpy(void *dst, const void *src, size_t c); +#endif + +void call_memcpy() { + char dst[10]; + char src[20]; + memcpy(dst, src, 20); // expected-warning {{memcpy' will always overflow; destination buffer has size 10, but size argument is 20}} +} + +void call_memcpy_type() { + struct pair { + int first; + int second; + }; + struct pair p; + char buf[20]; + memcpy(&p.first, buf, 20); +#ifdef USE_PASS_OBJECT_SIZE + // Use the more strict checking mode on the pass_object_size attribute: + // expected-warning@-3 {{memcpy' will always overflow; destination buffer has size 4, but size argument is 20}} +#else + // Or just fallback to type 0: + // expected-warning@-6 {{memcpy' will always overflow; destination buffer has size 8, but size argument is 20}} +#endif +} + +void call_strncat() { + char s1[10], s2[20]; + __builtin_strncat(s2, s1, 20); + __builtin_strncat(s1, s2, 20); // expected-warning {{'__builtin_strncat' size argument is too large; destination buffer has size 10, but size argument is 20}} +} + +void call_strncpy() { + char s1[10], s2[20]; + __builtin_strncpy(s2, s1, 20); + __builtin_strncpy(s1, s2, 20); // expected-warning {{'__builtin_strncpy' size argument is too large; destination buffer has size 10, but size argument is 20}} +} + +void call_stpncpy() { + char s1[10], s2[20]; + __builtin_stpncpy(s2, s1, 20); + __builtin_stpncpy(s1, s2, 20); // expected-warning {{'__builtin_stpncpy' size argument is too large; destination buffer has size 10, but size argument is 20}} +} + +void call_memmove() { + char s1[10], s2[20]; + __builtin_memmove(s2, s1, 20); + __builtin_memmove(s1, s2, 20); // expected-warning {{'__builtin_memmove' will always overflow; destination buffer has size 10, but size argument is 20}} +} + +void call_memset() { + char buf[10]; + __builtin_memset(buf, 0xff, 10); + __builtin_memset(buf, 0xff, 11); // expected-warning {{'__builtin_memset' will always overflow; destination buffer has size 10, but size argument is 11}} +} + +void call_snprintf() { + char buf[10]; + __builtin_snprintf(buf, 10, "merp"); + __builtin_snprintf(buf, 11, "merp"); // expected-warning {{'__builtin_snprintf' size argument is too large; destination buffer has size 10, but size argument is 11}} +} + +void call_vsnprintf() { + char buf[10]; + __builtin_va_list list; + __builtin_vsnprintf(buf, 10, "merp", list); + __builtin_vsnprintf(buf, 11, "merp", list); // expected-warning {{'__builtin_vsnprintf' size argument is too large; destination buffer has size 10, but size argument is 11}} +} Index: clang/test/Sema/warn-strncat-size.c =================================================================== --- clang/test/Sema/warn-strncat-size.c +++ clang/test/Sema/warn-strncat-size.c @@ -39,7 +39,7 @@ strncat(dest, "AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA", sizeof(dest) - strlen(dest)); // expected-warning{{the value of the size argument in 'strncat' is too large, might lead to a buffer overflow}} expected-note {{change the argument to be the free space in the destination buffer minus the terminating null byte}} strncat((*s5)->f2[x], s2, sizeof(s2)); // expected-warning {{size argument in 'strncat' call appears to be size of the source}} expected-note {{change the argument to be the free space in the destination buffer minus the terminating null byte}} - strncat(s1+3, s2, sizeof(s2)); // expected-warning {{size argument in 'strncat' call appears to be size of the source}} + strncat(s1+3, s2, sizeof(s2)); // expected-warning {{size argument in 'strncat' call appears to be size of the source}} expected-warning {{strncat' size argument is too large; destination buffer has size 97, but size argument is 200}} strncat(s4.f1, s2, sizeof(s2)); // expected-warning {{size argument in 'strncat' call appears to be size of the source}} expected-note {{change the argument to be the free space in the destination buffer minus the terminating null byte}} }