From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-8.5 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, USER_AGENT_MUTT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id BECBFC282DD for ; Thu, 23 May 2019 10:17:07 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 8B1672081C for ; Thu, 23 May 2019 10:17:07 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730412AbfEWKRH (ORCPT ); Thu, 23 May 2019 06:17:07 -0400 Received: from foss.arm.com ([217.140.101.70]:42332 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726846AbfEWKRG (ORCPT ); Thu, 23 May 2019 06:17:06 -0400 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.72.51.249]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 36DF9341; Thu, 23 May 2019 03:17:06 -0700 (PDT) Received: from fuggles.cambridge.arm.com (usa-sjc-imap-foss1.foss.arm.com [10.72.51.249]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id D34083F718; Thu, 23 May 2019 03:17:04 -0700 (PDT) Date: Thu, 23 May 2019 11:17:02 +0100 From: Will Deacon To: "Eric W. Biederman" Cc: linux-kernel@vger.kernel.org, Linux Containers , Oleg Nesterov , linux-arch@vger.kernel.org, Dave Martin , James Morse Subject: Re: [REVIEW][PATCH 03/26] signal/arm64: Use force_sig not force_sig_fault for SIGKILL Message-ID: <20190523101702.GG26646@fuggles.cambridge.arm.com> References: <20190523003916.20726-1-ebiederm@xmission.com> <20190523003916.20726-4-ebiederm@xmission.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20190523003916.20726-4-ebiederm@xmission.com> User-Agent: Mutt/1.11.1+86 (6f28e57d73f2) () Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, May 22, 2019 at 07:38:53PM -0500, Eric W. Biederman wrote: > It really only matters to debuggers but the SIGKILL does not have any > si_codes that use the fault member of the siginfo union. Correct this > the simple way and call force_sig instead of force_sig_fault when the > signal is SIGKILL. > > Cc: stable@vger.kernel.org > Cc: Dave Martin > Cc: James Morse > Cc: Will Deacon > Fixes: af40ff687bc9 ("arm64: signal: Ensure si_code is valid for all fault signals") > Signed-off-by: "Eric W. Biederman" > --- > arch/arm64/kernel/traps.c | 5 +++++ > 1 file changed, 5 insertions(+) > > diff --git a/arch/arm64/kernel/traps.c b/arch/arm64/kernel/traps.c > index ade32046f3fe..0feb17bdcaa0 100644 > --- a/arch/arm64/kernel/traps.c > +++ b/arch/arm64/kernel/traps.c > @@ -282,6 +282,11 @@ void arm64_notify_die(const char *str, struct pt_regs *regs, > current->thread.fault_address = 0; > current->thread.fault_code = err; > > + if (signo == SIGKILL) { > + arm64_show_signal(signo, str); > + force_sig(signo, current); > + return; > + } I know it's a bit of a misnomer, but I'd rather do this check inside arm64_force_sig_fault, since I think we have other callers (e.g. do_bad_area()) which also blindly pass in SIGKILL here. We could rename the thing if necessary. Will