From: "usa (Usaku NAKAMURA)" Date: 2013-02-05T17:07:14+09:00 Subject: [ruby-core:51868] [Backport93 - Backport #7775][Assigned] backport r38993 (ignore truncated part of socket address) to 1.9.3 Issue #7775 has been updated by usa (Usaku NAKAMURA). Status changed from Open to Assigned Assignee set to usa (Usaku NAKAMURA) ---------------------------------------- Backport #7775: backport r38993 (ignore truncated part of socket address) to 1.9.3 https://bugs.ruby-lang.org/issues/7775#change-35855 Author: akr (Akira Tanaka) Status: Assigned Priority: Normal Assignee: usa (Usaku NAKAMURA) Category: Target version: Please apply the attached patch, sockaddr-ignore-truncated-r38993-to-193.patch, to Ruby 1.9.3. The patch modifies returned addrlen after getsockaddr, getpeername and accept. They takes a buffer with the length and kernel returns a socket address in the buffer and returns its length. When a socket address length is longer than the buffer length, Most OS returns the real socket address length. (Exception: NetBSD returns the buffer length.) Apart from that, some OS provide a way to create Unix domain socket longer than sockaddr_un. For example, since GNU/Linux adds a NUL for pathname which is not NUL-terminated, giving sizeof(sun_path) non-NUL-terminated path to bind() creates a socket address which is one byte longer than sizeof(struct sockaddr_un). In that case, rb_str_new(socketaddress->sun_path, returned_length), rb_str_new reads a byte just after the buffer. The patch modifies the returned length as shorten to the buffer length to avoid such read. It is not a problem on GNU/Linux because the truncated data is always a NUL because GNU/Linux forbid a pathname longer than sizeof(sun_path) for Unix domain socket. Note that providing larger buffer for getsockname/getpeername/accept seems a practical option but it is another issue. Also note that retrying the system calls is not general solution because accept() is not retryable -- retrying accept() waits a next connection. -- http://bugs.ruby-lang.org/