[ruby-core:80647] [Ruby trunk Bug#13412] Infinite recursion with define_method may cause silent SEGV or cfp consistency error

Issue #13412 has been updated by wanabe (_ wanabe).

File stderr.log added

Looks like inconsistency longjmp().

I added debug print:

```
diff --git a/vm_insnhelper.c b/vm_insnhelper.c
index 21a358cb30..1a19ae397a 100644
--- a/vm_insnhelper.c
+++ b/vm_insnhelper.c
@@ -1766,7 +1766,9 @@ vm_call_cfunc_with_frame(rb_thread_t *th, rb_control_frame_t *reg_cfp, struct rb
 
     reg_cfp->sp -= argc + 1;
     VM_PROFILE_UP(R2C_CALL);
+    fprintf(stderr, ">> ccwf %x %x %x\n", &val, reg_cfp, th->cfp);
     val = (*cfunc->invoker)(cfunc->func, recv, argc, reg_cfp->sp + 1);
+    fprintf(stderr, "<< ccwf %x %x %x\n", &val, reg_cfp, th->cfp);
 
     if (reg_cfp != th->cfp + 1) {
	rb_bug("vm_call_cfunc - cfp consistency error");
```

normal case output:

```
$ ./miniruby bug.rb
>> ccwf de222b70 c68cbfb0 c68cbf80
<< ccwf de222b70 c68cbfb0 c68cbf80
>> ccwf de222b70 c68cbfb0 c68cbf80
>> ccwf de2216d0 c68cbf50 c68cbf20
<< ccwf de2216d0 c68cbf50 c68cbf20
<< ccwf de222b70 c68cbfb0 c68cbf80
```

[BUG] case output:

```
$ ./miniruby bug.rb
>> ccwf ca6fe2f0 53f7ffb0 53f7ff80
<< ccwf ca6fe2f0 53f7ffb0 53f7ff80
>> ccwf ca6fe2f0 53f7ffb0 53f7ff80
>> ccwf ca6fce50 53f7ff50 53f7ff20
<< ccwf ca6fe2f0 53f7ffb0 53f7ff20
bug.rb:4: [BUG] vm_call_cfunc - cfp consistency error
ruby 2.5.0dev (2017-04-09 trunk 58286) [x86_64-linux]

(snipped and attached)
```

I expected the last `&val` value should be "ca6fce50" but "ca6fe2f0".
This is the value of previous stack frame.

----------------------------------------
Bug #13412: Infinite recursion with define_method may cause silent SEGV or cfp consistency error
https://bugs.ruby-lang.org/issues/13412#change-64156

* Author: wanabe (_ wanabe)
* Status: Open
* Priority: Normal
* Assignee: 
* Target version: 
* ruby -v: ruby 2.5.0dev (2017-04-09 trunk 58286) [x86_64-linux]
* Backport: 2.2: UNKNOWN, 2.3: UNKNOWN, 2.4: UNKNOWN
----------------------------------------
The script causes silent (no output [BUG]) SEGV or "cfp consistency error" on my environment.

```
define_method(:foo) { foo }

loop do
  1.times do
    1.times do
      begin
        foo
      rescue Exception
        nil
      end
    end
  end
end
```

I think this is related to #11430 (maybe same).

---Files--------------------------------
stderr.log (6.96 KB)


-- 
https://bugs.ruby-lang.org/

Unsubscribe: <mailto:[e-mail]?subject=unsubscribe>
<http://lists.ruby-lang.org/cgi-bin/mailman/options/ruby-core>