https://github.com/rniwa updated https://github.com/llvm/llvm-project/pull/81400
>From 04e18254efc4f671e0bbd9625c7e994fe47c1636 Mon Sep 17 00:00:00 2001
From: Ryosuke Niwa <rn...@webkit.org>
Date: Sun, 11 Feb 2024 00:07:30 -0800
Subject: [PATCH 1/2] [alpha.webkit.UncountedCallArgsChecker] Check the safety
of the object argument in a member function call.
This PR makes alpha.webkit.UncountedCallArgsChecker eplicitly check the safety
of the object argument in
a member function call.
---
.../WebKit/UncountedCallArgsChecker.cpp | 67 +++++++++++++------
.../Checkers/WebKit/uncounted-obj-arg.cpp | 18 +++++
2 files changed, 66 insertions(+), 19 deletions(-)
create mode 100644 clang/test/Analysis/Checkers/WebKit/uncounted-obj-arg.cpp
diff --git
a/clang/lib/StaticAnalyzer/Checkers/WebKit/UncountedCallArgsChecker.cpp
b/clang/lib/StaticAnalyzer/Checkers/WebKit/UncountedCallArgsChecker.cpp
index 31ccae8b097b89..cda96b70ea8735 100644
--- a/clang/lib/StaticAnalyzer/Checkers/WebKit/UncountedCallArgsChecker.cpp
+++ b/clang/lib/StaticAnalyzer/Checkers/WebKit/UncountedCallArgsChecker.cpp
@@ -70,6 +70,15 @@ class UncountedCallArgsChecker
// or std::function call operator).
unsigned ArgIdx = isa<CXXOperatorCallExpr>(CE) &&
isa_and_nonnull<CXXMethodDecl>(F);
+ if (auto *MemberCallExpr = dyn_cast<CXXMemberCallExpr>(CE)) {
+ auto *E = MemberCallExpr->getImplicitObjectArgument();
+ auto *ArgType = MemberCallExpr->getObjectType().getTypePtrOrNull();
+ std::optional<bool> IsUncounted =
+ isUncounted(ArgType->getAsCXXRecordDecl());
+ if (IsUncounted && *IsUncounted && !isPtrOriginSafe(E))
+ reportBugOnThis(E);
+ }
+
for (auto P = F->param_begin();
// FIXME: Also check variadic function parameters.
// FIXME: Also check default function arguments. Probably a
different
@@ -91,25 +100,7 @@ class UncountedCallArgsChecker
const auto *Arg = CE->getArg(ArgIdx);
- std::pair<const clang::Expr *, bool> ArgOrigin =
- tryToFindPtrOrigin(Arg, true);
-
- // Temporary ref-counted object created as part of the call argument
- // would outlive the call.
- if (ArgOrigin.second)
- continue;
-
- if (isa<CXXNullPtrLiteralExpr>(ArgOrigin.first)) {
- // foo(nullptr)
- continue;
- }
- if (isa<IntegerLiteral>(ArgOrigin.first)) {
- // FIXME: Check the value.
- // foo(NULL)
- continue;
- }
-
- if (isASafeCallArg(ArgOrigin.first))
+ if (isPtrOriginSafe(Arg))
continue;
reportBug(Arg, *P);
@@ -117,6 +108,28 @@ class UncountedCallArgsChecker
}
}
+ bool isPtrOriginSafe(const Expr *Arg) const {
+ std::pair<const clang::Expr *, bool> ArgOrigin =
+ tryToFindPtrOrigin(Arg, true);
+
+ // Temporary ref-counted object created as part of the call argument
+ // would outlive the call.
+ if (ArgOrigin.second)
+ return true;
+
+ if (isa<CXXNullPtrLiteralExpr>(ArgOrigin.first)) {
+ // foo(nullptr)
+ return true;
+ }
+ if (isa<IntegerLiteral>(ArgOrigin.first)) {
+ // FIXME: Check the value.
+ // foo(NULL)
+ return true;
+ }
+
+ return isASafeCallArg(ArgOrigin.first);
+ }
+
bool shouldSkipCall(const CallExpr *CE) const {
if (CE->getNumArgs() == 0)
return false;
@@ -183,6 +196,22 @@ class UncountedCallArgsChecker
Report->addRange(CallArg->getSourceRange());
BR->emitReport(std::move(Report));
}
+
+ void reportBugOnThis(const Expr *CallArg) const {
+ assert(CallArg);
+
+ SmallString<100> Buf;
+ llvm::raw_svector_ostream Os(Buf);
+
+ Os << "Call argument for 'this' parameter is uncounted and unsafe.";
+
+ const SourceLocation SrcLocToReport = CallArg->getSourceRange().getBegin();
+
+ PathDiagnosticLocation BSLoc(SrcLocToReport, BR->getSourceManager());
+ auto Report = std::make_unique<BasicBugReport>(Bug, Os.str(), BSLoc);
+ Report->addRange(CallArg->getSourceRange());
+ BR->emitReport(std::move(Report));
+ }
};
} // namespace
diff --git a/clang/test/Analysis/Checkers/WebKit/uncounted-obj-arg.cpp
b/clang/test/Analysis/Checkers/WebKit/uncounted-obj-arg.cpp
new file mode 100644
index 00000000000000..e5e39e3faac714
--- /dev/null
+++ b/clang/test/Analysis/Checkers/WebKit/uncounted-obj-arg.cpp
@@ -0,0 +1,18 @@
+// RUN: %clang_analyze_cc1
-analyzer-checker=alpha.webkit.UncountedCallArgsChecker -verify %s
+
+#include "mock-types.h"
+
+class RefCounted {
+public:
+ void ref() const;
+ void deref() const;
+ void someFunction();
+};
+
+RefCounted* refCountedObj();
+
+void test()
+{
+ refCountedObj()->someFunction();
+ // expected-warning@-1{{Call argument for 'this' parameter is uncounted and
unsafe}}
+}
>From 2d780389a46e5c053053c1432d2ec3af2a7653e9 Mon Sep 17 00:00:00 2001
From: Ryosuke Niwa <rn...@webkit.org>
Date: Tue, 13 Feb 2024 19:36:09 -0800
Subject: [PATCH 2/2] Address the review comment. Namely avoid calling
getTypePtrOrNull and don't use raw_svector_ostream.
---
.../Checkers/WebKit/UncountedCallArgsChecker.cpp | 9 ++-------
1 file changed, 2 insertions(+), 7 deletions(-)
diff --git
a/clang/lib/StaticAnalyzer/Checkers/WebKit/UncountedCallArgsChecker.cpp
b/clang/lib/StaticAnalyzer/Checkers/WebKit/UncountedCallArgsChecker.cpp
index cda96b70ea8735..c8e5582ebf00ad 100644
--- a/clang/lib/StaticAnalyzer/Checkers/WebKit/UncountedCallArgsChecker.cpp
+++ b/clang/lib/StaticAnalyzer/Checkers/WebKit/UncountedCallArgsChecker.cpp
@@ -72,7 +72,7 @@ class UncountedCallArgsChecker
if (auto *MemberCallExpr = dyn_cast<CXXMemberCallExpr>(CE)) {
auto *E = MemberCallExpr->getImplicitObjectArgument();
- auto *ArgType = MemberCallExpr->getObjectType().getTypePtrOrNull();
+ QualType ArgType = MemberCallExpr->getObjectType();
std::optional<bool> IsUncounted =
isUncounted(ArgType->getAsCXXRecordDecl());
if (IsUncounted && *IsUncounted && !isPtrOriginSafe(E))
@@ -200,15 +200,10 @@ class UncountedCallArgsChecker
void reportBugOnThis(const Expr *CallArg) const {
assert(CallArg);
- SmallString<100> Buf;
- llvm::raw_svector_ostream Os(Buf);
-
- Os << "Call argument for 'this' parameter is uncounted and unsafe.";
-
const SourceLocation SrcLocToReport = CallArg->getSourceRange().getBegin();
PathDiagnosticLocation BSLoc(SrcLocToReport, BR->getSourceManager());
- auto Report = std::make_unique<BasicBugReport>(Bug, Os.str(), BSLoc);
+ auto Report = std::make_unique<BasicBugReport>(Bug, "Call argument for
'this' parameter is uncounted and unsafe.", BSLoc);
Report->addRange(CallArg->getSourceRange());
BR->emitReport(std::move(Report));
}
_______________________________________________
cfe-commits mailing list
cfe-commits@lists.llvm.org
https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
