Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755206AbdCTROZ (ORCPT ); Mon, 20 Mar 2017 13:14:25 -0400 Received: from www62.your-server.de ([213.133.104.62]:37399 "EHLO www62.your-server.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753632AbdCTROW (ORCPT ); Mon, 20 Mar 2017 13:14:22 -0400 Message-ID: <58D00DBD.5080702@iogearbox.net> Date: Mon, 20 Mar 2017 18:13:33 +0100 From: Daniel Borkmann User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:31.0) Gecko/20100101 Thunderbird/31.7.0 MIME-Version: 1.0 To: Elena Reshetova CC: ast@fb.com, linux-kernel@vger.kernel.org, peterz@infradead.org, netdev@vger.kernel.org, Hans Liljestrand , Kees Cook , David Windsor Subject: Re: [PATCH] net: convert sk_filter.refcnt from atomic_t to refcount_t References: <1490002641-10498-1-git-send-email-elena.reshetova@intel.com> In-Reply-To: <1490002641-10498-1-git-send-email-elena.reshetova@intel.com> Content-Type: text/plain; charset=windows-1252; format=flowed Content-Transfer-Encoding: 7bit X-Authenticated-Sender: daniel@iogearbox.net Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1498 Lines: 47 On 03/20/2017 10:37 AM, Elena Reshetova wrote: [...] > diff --git a/net/core/filter.c b/net/core/filter.c > index ebaeaf2..389cb8d 100644 > --- a/net/core/filter.c > +++ b/net/core/filter.c > @@ -928,7 +928,7 @@ static void sk_filter_release_rcu(struct rcu_head *rcu) > */ > static void sk_filter_release(struct sk_filter *fp) > { > - if (atomic_dec_and_test(&fp->refcnt)) > + if (refcount_dec_and_test(&fp->refcnt)) > call_rcu(&fp->rcu, sk_filter_release_rcu); > } > > @@ -943,20 +943,27 @@ void sk_filter_uncharge(struct sock *sk, struct sk_filter *fp) > /* try to charge the socket memory if there is space available > * return true on success > */ > -bool sk_filter_charge(struct sock *sk, struct sk_filter *fp) > +bool __sk_filter_charge(struct sock *sk, struct sk_filter *fp) And this then becomes: static bool __sk_filter_charge(...) > { > u32 filter_size = bpf_prog_size(fp->prog->len); > > /* same check as in sock_kmalloc() */ > if (filter_size <= sysctl_optmem_max && > atomic_read(&sk->sk_omem_alloc) + filter_size < sysctl_optmem_max) { > - atomic_inc(&fp->refcnt); > atomic_add(filter_size, &sk->sk_omem_alloc); > return true; > } > return false; > } Since here is just all in slow-path, looks fine to me if the above is addressed as well in v3: Acked-by: Daniel Borkmann Please make sure you add [PATCH net-next] in your subject in future so that it's clear which tree this goes to. Thanks, Daniel