Skip to content

Disallow explicit cast to nt_array_ptr in checked scopes (#391) #626

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Merged
dtarditi merged 2 commits into from
Jul 18, 2019
Merged

Disallow explicit cast to nt_array_ptr in checked scopes (#391) #626

Show file tree
Hide file tree
Changes from 1 commit
Commits
Show all changes
2 commits
Select commit Hold shift + click to select a range
a53808e
Disallow explicit cast to nt_array_ptr in checked scopes (#391)
jiezhoucs Jul 9, 2019
8b2bc5b
Cleaned up the code that disallows casting to nt_array_ptr.
jiezhoucs Jul 10, 2019
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
4 changes: 4 additions & 0 deletions include/clang/Basic/DiagnosticSemaKinds.td
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -9867,6 +9867,10 @@ def err_bounds_type_annotation_lost_checking : Error<
def err_checked_scope_no_assume_bounds_casting : Error<
"_Assume_bounds_cast not allowed in a checked scope or function">;

def err_checked_scope_no_cast_to_nt_array_ptr : Error<
"%0 cannot be cast to %1 in a checked scope because "
"%0 might not point to a null-terminated array">;

def err_checked_on_non_function : Error<
"%select{'_Unchecked'|'_Checked _Bounds_only|'_Checked'}0 "
"can only appear on functions">;
Expand Down
16 changes: 16 additions & 0 deletions lib/Sema/SemaCast.cpp
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -2700,6 +2700,22 @@ void CastOperation::CheckCStyleCast(bool IsCheckedScope) {
SrcExpr = ExprError();
return;
}

// Disallow cast from other Checked Pointer types to nt_arary_ptr because
// the SrcType might not point to a NULL-terminated array.
if (DestType->isPointerType()) {
if (cast<PointerType>(DestType)->getKind() == CheckedPointerKind::NtArray) {
Copy link
Member

@dtarditi dtarditi Jul 9, 2019

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

Could you use the function isCheckedPointerNtArrayType for testing whether a type is or is not an nt_array_ptr type?

Copy link
Contributor Author

@jiezhoucs jiezhoucs Jul 10, 2019

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

I have updated the code as suggested.

if (SrcType->isPointerType() &&
cast<PointerType>(SrcType)->getKind() != CheckedPointerKind::NtArray) {
Self.Diag(SrcExpr.get()->getExprLoc(),
diag::err_checked_scope_no_cast_to_nt_array_ptr)
<< SrcType << DestType << SrcExpr.get()->getSourceRange();
SrcExpr = ExprError();
return;
}
}
}

}

DiagnoseCastOfObjCSEL(Self, SrcExpr, DestType);
Expand Down