From mboxrd@z Thu Jan 1 00:00:00 1970 From: Alexei Starovoitov Subject: Re: [PATCH net-next] bpf: restore skb->sk before pskb_trim() call Date: Wed, 26 Apr 2017 13:53:23 -0700 Message-ID: <20170426205322.fiixm7fvx3sg7luv@ast-mbp> References: <1493222963.6453.77.camel@edumazet-glaptop3.roam.corp.google.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: David Miller , netdev , Andrey Konovalov , Willem de Bruijn To: Eric Dumazet Return-path: Received: from mail-pf0-f195.google.com ([209.85.192.195]:36540 "EHLO mail-pf0-f195.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S937706AbdDZUx1 (ORCPT ); Wed, 26 Apr 2017 16:53:27 -0400 Received: by mail-pf0-f195.google.com with SMTP id v14so2578664pfd.3 for ; Wed, 26 Apr 2017 13:53:27 -0700 (PDT) Content-Disposition: inline In-Reply-To: <1493222963.6453.77.camel@edumazet-glaptop3.roam.corp.google.com> Sender: netdev-owner@vger.kernel.org List-ID: On Wed, Apr 26, 2017 at 09:09:23AM -0700, Eric Dumazet wrote: > From: Eric Dumazet > > While testing a fix [1] in ___pskb_trim(), addressing the WARN_ON_ONCE() > in skb_try_coalesce() reported by Andrey, I found that we had an skb > with skb->sk set but no skb->destructor. > > This invalidated heuristic found in commit 158f323b9868 ("net: adjust > skb->truesize in pskb_expand_head()") and in cited patch. > > Considering the BUG_ON(skb->sk) we have in skb_orphan(), we should > restrain the temporary setting to a minimal section. > > [1] https://patchwork.ozlabs.org/patch/755570/ > net: adjust skb->truesize in ___pskb_trim() > > Fixes: 8f917bba0042 ("bpf: pass sk to helper functions") > Signed-off-by: Eric Dumazet > Cc: Willem de Bruijn > Cc: Andrey Konovalov Ahh. Thanks for the fix. Acked-by: Alexei Starovoitov