From: Nobuyoshi Nakada <nobu@...>
Date: 2010-10-24T14:48:29+09:00
Subject: [ruby-core:32893] Re: [Ruby-Bug#3840][Open] Ruby 1.9.2p0 crashes using Rails 3.0 on repeated browser refresh

Hi,

At Thu, 16 Sep 2010 21:40:03 +0900,
Sean O'Neil wrote in [ruby-core:32428]:
> I can eliminate this crash by changing the Ruby source to
> check for NULL before referencing the pointer. However, it
> may only hide the issue, which may come back to bite me
> later. So, does this sound like a problem that needs to be
> fixed in the Ruby code, or a thread-safety issue in Rails?

Your investigation seems correct, and I agree that it should be
noticed earlier.  I think Rails has a thread-safety issue but
the crash is definitely a bug of Ruby itself.  Does this patch
fix it?


diff --git a/io.c b/io.c
index 4b8d34a..67d97f2 100644
--- a/io.c
+++ b/io.c
@@ -1722,6 +1722,7 @@ fill_cbuf(rb_io_t *fptr, int ec_flags)
             if (fptr->rbuf_len == 0) {
 		READ_CHECK(fptr);
                 if (io_fillbuf(fptr) == -1) {
+                    rb_io_check_closed(fptr);
                     ds = dp = (unsigned char *)fptr->cbuf + fptr->cbuf_off + fptr->cbuf_len;
                     de = (unsigned char *)fptr->cbuf + fptr->cbuf_capa;
                     res = rb_econv_convert(fptr->readconv, NULL, NULL, &dp, de, 0);


-- 
Nobu Nakada