io.c: fix race between read and close

* io.c (io_fillbuf): fix race between read and close, in the case
  the IO gets closed before the reading thread achieve the lock.
  [ruby-core:78845] [Bug #13076]

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@57199 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

1 files changed, 2 insertions, 1 deletions

diff --git a/io.c b/io.c
index af2d54bd3b..d36bd48d5c 100644
--- a/io.c
+++ b/io.c
@@ -424,7 +424,7 @@ rb_cloexec_fcntl_dupfd(int fd, int minfd)
     if (!READ_DATA_PENDING(fptr)) {\
 	WAIT_FD_IN_WIN32(fptr);\
 	rb_io_check_closed(fptr);\
-     }\
+    }\
 } while(0)
 
 #ifndef S_ISSOCK
@@ -1775,6 +1775,7 @@ io_fillbuf(rb_io_t *fptr)
 		rb_syserr_fail_path(e, path);
 	    }
         }
+	if (r > 0) READ_CHECK(fptr);
         fptr->rbuf.off = 0;
         fptr->rbuf.len = (int)r; /* r should be <= rbuf_capa */
         if (r == 0)