From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753283AbbCSNCo (ORCPT ); Thu, 19 Mar 2015 09:02:44 -0400 Received: from mx1.redhat.com ([209.132.183.28]:38080 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750756AbbCSNCm (ORCPT ); Thu, 19 Mar 2015 09:02:42 -0400 Date: Thu, 19 Mar 2015 14:00:46 +0100 From: Oleg Nesterov To: Vladimir Davydov Cc: linux-kernel@vger.kernel.org, Andrew Morton , Richard Weinberger , "Paul E. McKenney" Subject: Re: [PATCH] signal: improve warning about using SI_TKILL in rt_[tg]sigqueueinfo Message-ID: <20150319130045.GA7201@redhat.com> References: <1426758781-11746-1-git-send-email-vdavydov@parallels.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1426758781-11746-1-git-send-email-vdavydov@parallels.com> User-Agent: Mutt/1.5.18 (2008-05-17) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 03/19, Vladimir Davydov wrote: > > Sending SI_TKILL from rt_[tg]sigqueueinfo was deprecated, so now we > issue a warning on the first attempt of doing it. We use WARN_ON_ONCE, > which is not informative and, what is worse, taints the kernel, making > the trinity syscall fuzzer complain false-positively from time to time. > > This patch therefore substitutes the WARN_ON_ONCE with a pr_warn_once. Agreed. but perhaps we can simply remove this warning at all? > Signed-off-by: Vladimir Davydov > --- > kernel/signal.c | 16 +++++++++++----- > 1 file changed, 11 insertions(+), 5 deletions(-) > > diff --git a/kernel/signal.c b/kernel/signal.c > index a390499943e4..3cbcd94457af 100644 > --- a/kernel/signal.c > +++ b/kernel/signal.c > @@ -2993,8 +2993,11 @@ static int do_rt_sigqueueinfo(pid_t pid, int sig, siginfo_t *info) > */ > if ((info->si_code >= 0 || info->si_code == SI_TKILL) && > (task_pid_vnr(current) != pid)) { > - /* We used to allow any < 0 si_code */ > - WARN_ON_ONCE(info->si_code < 0); > + /* We used to allow SI_TKILL */ > + if (info->si_code == SI_TKILL) > + pr_warn_once("%s (%d): Sending SI_TKILL from " > + "rt_sigqueueinfo is deprecated\n", > + current->comm, current->pid); > return -EPERM; > } > info->si_signo = sig; > @@ -3041,10 +3044,13 @@ static int do_rt_tgsigqueueinfo(pid_t tgid, pid_t pid, int sig, siginfo_t *info) > /* Not even root can pretend to send signals from the kernel. > * Nor can they impersonate a kill()/tgkill(), which adds source info. > */ > - if (((info->si_code >= 0 || info->si_code == SI_TKILL)) && > + if ((info->si_code >= 0 || info->si_code == SI_TKILL) && > (task_pid_vnr(current) != pid)) { > - /* We used to allow any < 0 si_code */ > - WARN_ON_ONCE(info->si_code < 0); > + /* We used to allow SI_TKILL */ > + if (info->si_code == SI_TKILL) > + pr_warn_once("%s (%d): Sending SI_TKILL from " > + "rt_tgsigqueueinfo is deprecated\n", > + current->comm, current->pid); > return -EPERM; > } > info->si_signo = sig; > -- > 1.7.10.4 >