From mboxrd@z Thu Jan 1 00:00:00 1970 From: Arnaldo Carvalho de Melo Subject: Re: struct sock size limit? Date: Sun, 27 Oct 2002 03:18:40 -0300 Sender: netdev-bounce@oss.sgi.com Message-ID: <20021027061840.GA4720@conectiva.com.br> References: Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: netdev@oss.sgi.com Return-path: To: Cheng Jin Content-Disposition: inline In-Reply-To: Errors-to: netdev-bounce@oss.sgi.com List-Id: netdev.vger.kernel.org Em Sat, Oct 26, 2002 at 10:44:03PM -0700, Cheng Jin escreveu: > Hi, > > I have been adding members to struct sock (by changing struct tcp_opt) in > linux 2.4.18-3 kernel. I haven't had problems with the kernel until > today. When I added a few more bytes (~ 20 bytes) on top of my old > addition (around 80 bytes), the kernel would crash calling udp_sendmsg beware the data dependencies of struct sock and tcp_tw_bucket, etc, I bet you're adding new struct members at the start of struct sock, see the comment in include/net/tcp.h, just above struct tcp_tw_bucket definition... and also study current include/net/sock.h in 2.5, this thing was all changed (for the better 8) ). > (syslogd initialization). I suspect that there may be some kind of size > limit with struct sock/tcp_opt. The TCP connected state is checked > from within udp_sendmsg (no idea why that is so). so look at other protocols such as decnet that also uses the TCP_ state macros :-) its just reusing those macros. > I searched around on google, but didn't find anything on struct sock or > struct tcp_opt. Does anyone know whether the size of struct sock/tcp_opt > is capped? > > Thanks a lot, > > Cheng > > Lab # 626 395 8820 >