[Bug #20915] Fix SEGV with TracePoint#parameters and aliased C method

The following snippet results with a SEGV:

```ruby
C = Class.new do
  alias_method :new_to_s, :to_s
end

TracePoint.new(:c_call, &:parameters).enable { C.new.new_to_s }
```

at MRI 3.3.6 and ruby 3.4.0dev

The root cause of the issue lies in the `rb_tracearg_parameters` function
within the `RUBY_EVENT_C_RETURN` branch. Specifically, when the invoked
method is an alias for a C function,
`rb_method_entry_without_refinements(..., trace_arg->called_id, ...)`
may return NULL. In that case we can fallback to `trace_arg->id`.
This commit is contained in:
viralpraxis 2024-11-30 00:13:54 +03:00 committed by Peter Zhu
parent 88764dde78
commit 660b995365
Notes: git 2024-11-29 23:43:05 +00:00
2 changed files with 19 additions and 0 deletions

View File

@ -94,6 +94,22 @@ class TestSetTraceFunc < Test::Unit::TestCase
assert_equal([[:req]], parameters)
end
def test_c_call_aliased_method
# [Bug #20915]
klass = Class.new do
alias_method :new_method, :method
end
instance = klass.new
parameters = nil
TracePoint.new(:c_call) do |tp|
parameters = tp.parameters
end.enable { instance.new_method(:to_s) }
assert_equal([[:req]], parameters)
end
def test_call
events = []
name = "#{self.class}\##{__method__}"

View File

@ -937,6 +937,9 @@ rb_tracearg_parameters(rb_trace_arg_t *trace_arg)
const rb_method_entry_t *me;
VALUE iclass = Qnil;
me = rb_method_entry_without_refinements(trace_arg->klass, trace_arg->called_id, &iclass);
if (!me) {
me = rb_method_entry_without_refinements(trace_arg->klass, trace_arg->id, &iclass);
}
return rb_unnamed_parameters(rb_method_entry_arity(me));
}
break;