From mboxrd@z Thu Jan 1 00:00:00 1970 From: David Miller Subject: Re: [PATCH net] net: sctp: use MAX_HEADER for headroom reserve in output path Date: Tue, 09 Dec 2014 13:24:55 -0500 (EST) Message-ID: <20141209.132455.111095755280708974.davem@davemloft.net> References: <1417605238-9936-1-git-send-email-dborkman@redhat.com> Mime-Version: 1.0 Content-Type: Text/Plain; charset=iso-8859-2 Content-Transfer-Encoding: QUOTED-PRINTABLE Cc: linux-sctp@vger.kernel.org, netdev@vger.kernel.org, robert@swiecki.net To: dborkman@redhat.com Return-path: Received: from shards.monkeyblade.net ([149.20.54.216]:37212 "EHLO shards.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751019AbaLISY6 convert rfc822-to-8bit (ORCPT ); Tue, 9 Dec 2014 13:24:58 -0500 In-Reply-To: <1417605238-9936-1-git-send-email-dborkman@redhat.com> Sender: netdev-owner@vger.kernel.org List-ID: =46rom: Daniel Borkmann Date: Wed, 3 Dec 2014 12:13:58 +0100 > To accomodate for enough headroom for tunnels, use MAX_HEADER instead > of LL_MAX_HEADER. Robert reported that he has hit after roughly 40hrs > of trinity an skb_under_panic() via SCTP output path (see reference). > I couldn't reproduce it from here, but not using MAX_HEADER as elsewh= ere > in other protocols might be one possible cause for this. >=20 > In any case, it looks like accounting on chunks themself seems to loo= k > good as the skb already passed the SCTP output path and did not hit > any skb_over_panic(). Given tunneling was enabled in his .config, the > headroom would have been expanded by MAX_HEADER in this case. >=20 > Reported-by: Robert =A6wi=EAcki > Reference: https://lkml.org/lkml/2014/12/1/507 > Fixes: 594ccc14dfe4d ("[SCTP] Replace incorrect use of dev_alloc_skb = with alloc_skb in sctp_packet_transmit().") > Signed-off-by: Daniel Borkmann Applied and queued up for -stable, thanks.